diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst new file mode 100644 index 000000000000..7297f9478459 --- /dev/null +++ b/Documentation/trace/fprobetrace.rst @@ -0,0 +1,188 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================== +Fprobe-based Event Tracing +========================== + +.. Author: Masami Hiramatsu + +Overview +-------- + +Fprobe event is similar to the kprobe event, but limited to probe on +the function entry and exit only. It is good enough for many use cases +which only traces some specific functions. + +This document also covers tracepoint probe events (tprobe) since this +is also works only on the tracepoint entry. User can trace a part of +tracepoint argument, or the tracepoint without trace-event, which is +not exposed on tracefs. + +As same as other dynamic events, fprobe events and tracepoint probe +events are defined via `dynamic_events` interface file on tracefs. + +Synopsis of fprobe-events +------------------------- +:: + + f[:[GRP1/][EVENT1]] SYM [FETCHARGS] : Probe on function entry + f[MAXACTIVE][:[GRP1/][EVENT1]] SYM%return [FETCHARGS] : Probe on function exit + t[:[GRP2/][EVENT2]] TRACEPOINT [FETCHARGS] : Probe on tracepoint + + GRP1 : Group name for fprobe. If omitted, use "fprobes" for it. + GRP2 : Group name for tprobe. If omitted, use "tracepoints" for it. + EVENT1 : Event name for fprobe. If omitted, the event name is + "SYM__entry" or "SYM__exit". + EVENT2 : Event name for tprobe. If omitted, the event name is + the same as "TRACEPOINT", but if the "TRACEPOINT" starts + with a digit character, "_TRACEPOINT" is used. + MAXACTIVE : Maximum number of instances of the specified function that + can be probed simultaneously, or 0 for the default value + as defined in Documentation/trace/fprobe.rst + + FETCHARGS : Arguments. Each probe can have up to 128 args. + ARG : Fetch "ARG" function argument using BTF (only for function + entry or tracepoint.) (\*1) + @ADDR : Fetch memory at ADDR (ADDR should be in kernel) + @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) + $stackN : Fetch Nth entry of stack (N >= 0) + $stack : Fetch stack address. + $argN : Fetch the Nth function argument. (N >= 1) (\*2) + $retval : Fetch return value.(\*3) + $comm : Fetch current task comm. + +|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*4)(\*5) + \IMM : Store an immediate value to the argument. + NAME=FETCHARG : Set NAME as the argument name of FETCHARG. + FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types + (u8/u16/u32/u64/s8/s16/s32/s64), hexadecimal types + (x8/x16/x32/x64), "char", "string", "ustring", "symbol", "symstr" + and bitfield are supported. + + (\*1) This is available only when BTF is enabled. + (\*2) only for the probe on function entry (offs == 0). + (\*3) only for return probe. + (\*4) this is useful for fetching a field of data structures. + (\*5) "u" means user-space dereference. + +For the details of TYPE, see :ref:`kprobetrace documentation `. + +BTF arguments +------------- +BTF (BPF Type Format) argument allows user to trace function and tracepoint +parameters by its name instead of ``$argN``. This feature is available if the +kernel is configured with CONFIG_BPF_SYSCALL and CONFIG_DEBUG_INFO_BTF. +If user only specify the BTF argument, the event's argument name is also +automatically set by the given name. :: + + # echo 'f:myprobe vfs_read count pos' >> dynamic_events + # cat dynamic_events + f:fprobes/myprobe vfs_read count=count pos=pos + +It also chooses the fetch type from BTF information. For example, in the above +example, the ``count`` is unsigned long, and the ``pos`` is a pointer. Thus, both +are converted to 64bit unsigned long, but only ``pos`` has "%Lx" print-format as +below :: + + # cat events/fprobes/myprobe/format + name: myprobe + ID: 1313 + format: + field:unsigned short common_type; offset:0; size:2; signed:0; + field:unsigned char common_flags; offset:2; size:1; signed:0; + field:unsigned char common_preempt_count; offset:3; size:1; signed:0; + field:int common_pid; offset:4; size:4; signed:1; + + field:unsigned long __probe_ip; offset:8; size:8; signed:0; + field:u64 count; offset:16; size:8; signed:0; + field:u64 pos; offset:24; size:8; signed:0; + + print fmt: "(%lx) count=%Lu pos=0x%Lx", REC->__probe_ip, REC->count, REC->pos + +If user unsures the name of arguments, ``$arg*`` will be helpful. The ``$arg*`` +is expanded to all function arguments of the function or the tracepoint. :: + + # echo 'f:myprobe vfs_read $arg*' >> dynamic_events + # cat dynamic_events + f:fprobes/myprobe vfs_read file=file buf=buf count=count pos=pos + +BTF also affects the ``$retval``. If user doesn't set any type, the retval type is +automatically picked from the BTF. If the function returns ``void``, ``$retval`` +is rejected. + +Usage examples +-------------- +Here is an example to add fprobe events on ``vfs_read()`` function entry +and exit, with BTF arguments. +:: + + # echo 'f vfs_read $arg*' >> dynamic_events + # echo 'f vfs_read%return $retval' >> dynamic_events + # cat dynamic_events + f:fprobes/vfs_read__entry vfs_read file=file buf=buf count=count pos=pos + f:fprobes/vfs_read__exit vfs_read%return arg1=$retval + # echo 1 > events/fprobes/enable + # head -n 20 trace | tail + # TASK-PID CPU# ||||| TIMESTAMP FUNCTION + # | | | ||||| | | + sh-70 [000] ...1. 335.883195: vfs_read__entry: (vfs_read+0x4/0x340) file=0xffff888005cf9a80 buf=0x7ffef36c6879 count=1 pos=0xffffc900005aff08 + sh-70 [000] ..... 335.883208: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=1 + sh-70 [000] ...1. 335.883220: vfs_read__entry: (vfs_read+0x4/0x340) file=0xffff888005cf9a80 buf=0x7ffef36c6879 count=1 pos=0xffffc900005aff08 + sh-70 [000] ..... 335.883224: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=1 + sh-70 [000] ...1. 335.883232: vfs_read__entry: (vfs_read+0x4/0x340) file=0xffff888005cf9a80 buf=0x7ffef36c687a count=1 pos=0xffffc900005aff08 + sh-70 [000] ..... 335.883237: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=1 + sh-70 [000] ...1. 336.050329: vfs_read__entry: (vfs_read+0x4/0x340) file=0xffff888005cf9a80 buf=0x7ffef36c6879 count=1 pos=0xffffc900005aff08 + sh-70 [000] ..... 336.050343: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=1 + +You can see all function arguments and return values are recorded as signed int. + +Also, here is an example of tracepoint events on ``sched_switch`` tracepoint. +To compare the result, this also enables the ``sched_switch`` traceevent too. +:: + + # echo 't sched_switch $arg*' >> dynamic_events + # echo 1 > events/sched/sched_switch/enable + # echo 1 > events/tracepoints/sched_switch/enable + # echo > trace + # head -n 20 trace | tail + # TASK-PID CPU# ||||| TIMESTAMP FUNCTION + # | | | ||||| | | + sh-70 [000] d..2. 3912.083993: sched_switch: prev_comm=sh prev_pid=70 prev_prio=120 prev_state=S ==> next_comm=swapper/0 next_pid=0 next_prio=120 + sh-70 [000] d..3. 3912.083995: sched_switch: (__probestub_sched_switch+0x4/0x10) preempt=0 prev=0xffff88800664e100 next=0xffffffff828229c0 prev_state=1 + -0 [000] d..2. 3912.084183: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=rcu_preempt next_pid=16 next_prio=120 + -0 [000] d..3. 3912.084184: sched_switch: (__probestub_sched_switch+0x4/0x10) preempt=0 prev=0xffffffff828229c0 next=0xffff888004208000 prev_state=0 + rcu_preempt-16 [000] d..2. 3912.084196: sched_switch: prev_comm=rcu_preempt prev_pid=16 prev_prio=120 prev_state=I ==> next_comm=swapper/0 next_pid=0 next_prio=120 + rcu_preempt-16 [000] d..3. 3912.084196: sched_switch: (__probestub_sched_switch+0x4/0x10) preempt=0 prev=0xffff888004208000 next=0xffffffff828229c0 prev_state=1026 + -0 [000] d..2. 3912.085191: sched_switch: prev_comm=swapper/0 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=rcu_preempt next_pid=16 next_prio=120 + -0 [000] d..3. 3912.085191: sched_switch: (__probestub_sched_switch+0x4/0x10) preempt=0 prev=0xffffffff828229c0 next=0xffff888004208000 prev_state=0 + +As you can see, the ``sched_switch`` trace-event shows *cooked* parameters, on +the other hand, the ``sched_switch`` tracepoint probe event shows *raw* +parameters. This means you can access any field values in the task +structure pointed by the ``prev`` and ``next`` arguments. + +For example, usually ``task_struct::start_time`` is not traced, but with this +traceprobe event, you can trace it as below. +:: + + # echo 't sched_switch comm=+1896(next):string start_time=+1728(next):u64' > dynamic_events + # head -n 20 trace | tail + # TASK-PID CPU# ||||| TIMESTAMP FUNCTION + # | | | ||||| | | + sh-70 [000] d..3. 5606.686577: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="rcu_preempt" usage=1 start_time=245000000 + rcu_preempt-16 [000] d..3. 5606.686602: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="sh" usage=1 start_time=1596095526 + sh-70 [000] d..3. 5606.686637: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="swapper/0" usage=2 start_time=0 + -0 [000] d..3. 5606.687190: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="rcu_preempt" usage=1 start_time=245000000 + rcu_preempt-16 [000] d..3. 5606.687202: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="swapper/0" usage=2 start_time=0 + -0 [000] d..3. 5606.690317: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="kworker/0:1" usage=1 start_time=137000000 + kworker/0:1-14 [000] d..3. 5606.690339: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="swapper/0" usage=2 start_time=0 + -0 [000] d..3. 5606.692368: sched_switch: (__probestub_sched_switch+0x4/0x10) comm="kworker/0:1" usage=1 start_time=137000000 + +Currently, to find the offset of a specific field in the data structure, +you need to build kernel with debuginfo and run `perf probe` command with +`-D` option. e.g. +:: + + # perf probe -D "__probestub_sched_switch next->comm:string next->start_time" + p:probe/__probestub_sched_switch __probestub_sched_switch+0 comm=+1896(%cx):string start_time=+1728(%cx):u64 + +And replace the ``%cx`` with the ``next``. diff --git a/Documentation/trace/index.rst b/Documentation/trace/index.rst index ea25a9220f92..5092d6c13af5 100644 --- a/Documentation/trace/index.rst +++ b/Documentation/trace/index.rst @@ -13,6 +13,7 @@ Linux Tracing Technologies kprobes kprobetrace uprobetracer + fprobetrace tracepoints events events-kmem diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst index 651f9ab53f3e..8a2dfee38145 100644 --- a/Documentation/trace/kprobetrace.rst +++ b/Documentation/trace/kprobetrace.rst @@ -66,6 +66,8 @@ Synopsis of kprobe_events (\*3) this is useful for fetching a field of data structures. (\*4) "u" means user-space dereference. See :ref:`user_mem_access`. +.. _kprobetrace_types: + Types ----- Several types are supported for fetchargs. Kprobe tracer will access memory diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h index 47fefc7f363b..3e03758151f4 100644 --- a/include/linux/fprobe.h +++ b/include/linux/fprobe.h @@ -35,9 +35,11 @@ struct fprobe { int nr_maxactive; int (*entry_handler)(struct fprobe *fp, unsigned long entry_ip, - struct pt_regs *regs, void *entry_data); + unsigned long ret_ip, struct pt_regs *regs, + void *entry_data); void (*exit_handler)(struct fprobe *fp, unsigned long entry_ip, - struct pt_regs *regs, void *entry_data); + unsigned long ret_ip, struct pt_regs *regs, + void *entry_data); }; /* This fprobe is soft-disabled. */ @@ -64,6 +66,7 @@ int register_fprobe(struct fprobe *fp, const char *filter, const char *notfilter int register_fprobe_ips(struct fprobe *fp, unsigned long *addrs, int num); int register_fprobe_syms(struct fprobe *fp, const char **syms, int num); int unregister_fprobe(struct fprobe *fp); +bool fprobe_is_registered(struct fprobe *fp); #else static inline int register_fprobe(struct fprobe *fp, const char *filter, const char *notfilter) { @@ -81,6 +84,10 @@ static inline int unregister_fprobe(struct fprobe *fp) { return -EOPNOTSUPP; } +static inline bool fprobe_is_registered(struct fprobe *fp) +{ + return false; +} #endif /** diff --git a/include/linux/rethook.h b/include/linux/rethook.h index c8ac1e5afcd1..fdf26cd0e742 100644 --- a/include/linux/rethook.h +++ b/include/linux/rethook.h @@ -14,7 +14,7 @@ struct rethook_node; -typedef void (*rethook_handler_t) (struct rethook_node *, void *, struct pt_regs *); +typedef void (*rethook_handler_t) (struct rethook_node *, void *, unsigned long, struct pt_regs *); /** * struct rethook - The rethook management data structure. diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 7c4a0b72334e..3930e676436c 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -318,6 +318,7 @@ enum { TRACE_EVENT_FL_KPROBE_BIT, TRACE_EVENT_FL_UPROBE_BIT, TRACE_EVENT_FL_EPROBE_BIT, + TRACE_EVENT_FL_FPROBE_BIT, TRACE_EVENT_FL_CUSTOM_BIT, }; @@ -332,6 +333,7 @@ enum { * KPROBE - Event is a kprobe * UPROBE - Event is a uprobe * EPROBE - Event is an event probe + * FPROBE - Event is an function probe * CUSTOM - Event is a custom event (to be attached to an exsiting tracepoint) * This is set when the custom event has not been attached * to a tracepoint yet, then it is cleared when it is. @@ -346,6 +348,7 @@ enum { TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), TRACE_EVENT_FL_EPROBE = (1 << TRACE_EVENT_FL_EPROBE_BIT), + TRACE_EVENT_FL_FPROBE = (1 << TRACE_EVENT_FL_FPROBE_BIT), TRACE_EVENT_FL_CUSTOM = (1 << TRACE_EVENT_FL_CUSTOM_BIT), }; diff --git a/include/linux/tracepoint-defs.h b/include/linux/tracepoint-defs.h index e7c2276be33e..4dc4955f0fbf 100644 --- a/include/linux/tracepoint-defs.h +++ b/include/linux/tracepoint-defs.h @@ -35,6 +35,7 @@ struct tracepoint { struct static_call_key *static_call_key; void *static_call_tramp; void *iterator; + void *probestub; int (*regfunc)(void); void (*unregfunc)(void); struct tracepoint_func __rcu *funcs; diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 6811e43c1b5c..88c0ba623ee6 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -303,6 +303,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) __section("__tracepoints_strings") = #_name; \ extern struct static_call_key STATIC_CALL_KEY(tp_func_##_name); \ int __traceiter_##_name(void *__data, proto); \ + void __probestub_##_name(void *__data, proto); \ struct tracepoint __tracepoint_##_name __used \ __section("__tracepoints") = { \ .name = __tpstrtab_##_name, \ @@ -310,6 +311,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) .static_call_key = &STATIC_CALL_KEY(tp_func_##_name), \ .static_call_tramp = STATIC_CALL_TRAMP_ADDR(tp_func_##_name), \ .iterator = &__traceiter_##_name, \ + .probestub = &__probestub_##_name, \ .regfunc = _reg, \ .unregfunc = _unreg, \ .funcs = NULL }; \ @@ -330,6 +332,9 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) } \ return 0; \ } \ + void __probestub_##_name(void *__data, proto) \ + { \ + } \ DEFINE_STATIC_CALL(tp_func_##_name, __traceiter_##_name); #define DEFINE_TRACE(name, proto, args) \ diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 00e177de91cc..ce13f1a35251 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2127,6 +2127,7 @@ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs) NOKPROBE_SYMBOL(pre_handler_kretprobe); static void kretprobe_rethook_handler(struct rethook_node *rh, void *data, + unsigned long ret_addr, struct pt_regs *regs) { struct kretprobe *rp = (struct kretprobe *)data; diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index abe5c583bd59..61c541c36596 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -665,6 +665,32 @@ config BLK_DEV_IO_TRACE If unsure, say N. +config FPROBE_EVENTS + depends on FPROBE + depends on HAVE_REGS_AND_STACK_ACCESS_API + bool "Enable fprobe-based dynamic events" + select TRACING + select PROBE_EVENTS + select DYNAMIC_EVENTS + default y + help + This allows user to add tracing events on the function entry and + exit via ftrace interface. The syntax is same as the kprobe events + and the kprobe events on function entry and exit will be + transparently converted to this fprobe events. + +config PROBE_EVENTS_BTF_ARGS + depends on HAVE_FUNCTION_ARG_ACCESS_API + depends on FPROBE_EVENTS || KPROBE_EVENTS + depends on DEBUG_INFO_BTF && BPF_SYSCALL + bool "Support BTF function arguments for probe events" + default y + help + The user can specify the arguments of the probe event using the names + of the arguments of the probed function, when the probe location is a + kernel function entry or a tracepoint. + This is available only if BTF (BPF Type Format) support is enabled. + config KPROBE_EVENTS depends on KPROBES depends on HAVE_REGS_AND_STACK_ACCESS_API diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index c6651e16b557..64b61f67a403 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -104,6 +104,7 @@ obj-$(CONFIG_BOOTTIME_TRACING) += trace_boot.o obj-$(CONFIG_FTRACE_RECORD_RECURSION) += trace_recursion_record.o obj-$(CONFIG_FPROBE) += fprobe.o obj-$(CONFIG_RETHOOK) += rethook.o +obj-$(CONFIG_FPROBE_EVENTS) += trace_fprobe.o obj-$(CONFIG_TRACEPOINT_BENCHMARK) += trace_benchmark.o obj-$(CONFIG_RV) += rv/ diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 03b7f6b8e4f0..5f2dcabad202 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2652,7 +2652,8 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, static int kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, - struct pt_regs *regs, void *data) + unsigned long ret_ip, struct pt_regs *regs, + void *data) { struct bpf_kprobe_multi_link *link; @@ -2663,7 +2664,8 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, static void kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip, - struct pt_regs *regs, void *data) + unsigned long ret_ip, struct pt_regs *regs, + void *data) { struct bpf_kprobe_multi_link *link; diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 18d36842faf5..e4704ec26df7 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -46,7 +46,7 @@ static inline void __fprobe_handler(unsigned long ip, unsigned long parent_ip, } if (fp->entry_handler) - ret = fp->entry_handler(fp, ip, ftrace_get_regs(fregs), entry_data); + ret = fp->entry_handler(fp, ip, parent_ip, ftrace_get_regs(fregs), entry_data); /* If entry_handler returns !0, nmissed is not counted. */ if (rh) { @@ -112,7 +112,7 @@ static void fprobe_kprobe_handler(unsigned long ip, unsigned long parent_ip, } static void fprobe_exit_handler(struct rethook_node *rh, void *data, - struct pt_regs *regs) + unsigned long ret_ip, struct pt_regs *regs) { struct fprobe *fp = (struct fprobe *)data; struct fprobe_rethook_node *fpr; @@ -133,7 +133,7 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data, return; } - fp->exit_handler(fp, fpr->entry_ip, regs, + fp->exit_handler(fp, fpr->entry_ip, ret_ip, regs, fp->entry_data_size ? (void *)fpr->data : NULL); ftrace_test_recursion_unlock(bit); } @@ -348,6 +348,14 @@ int register_fprobe_syms(struct fprobe *fp, const char **syms, int num) } EXPORT_SYMBOL_GPL(register_fprobe_syms); +bool fprobe_is_registered(struct fprobe *fp) +{ + if (!fp || (fp->ops.saved_func != fprobe_handler && + fp->ops.saved_func != fprobe_kprobe_handler)) + return false; + return true; +} + /** * unregister_fprobe() - Unregister fprobe from ftrace * @fp: A fprobe data structure to be unregistered. @@ -360,8 +368,7 @@ int unregister_fprobe(struct fprobe *fp) { int ret; - if (!fp || (fp->ops.saved_func != fprobe_handler && - fp->ops.saved_func != fprobe_kprobe_handler)) + if (!fprobe_is_registered(fp)) return -EINVAL; /* diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c index 60f6cb2b486b..f32ee484391a 100644 --- a/kernel/trace/rethook.c +++ b/kernel/trace/rethook.c @@ -301,7 +301,8 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs, break; handler = READ_ONCE(rhn->rethook->handler); if (handler) - handler(rhn, rhn->rethook->data, regs); + handler(rhn, rhn->rethook->data, + correct_ret_addr, regs); if (first == node) break; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 074d0b2e19ed..b04f52e7cd28 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5672,10 +5672,17 @@ static const char readme_msg[] = " uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n" "\t\t\t Write into this file to define/undefine new trace events.\n" #endif -#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) +#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) || \ + defined(CONFIG_FPROBE_EVENTS) "\t accepts: event-definitions (one definition per line)\n" +#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) "\t Format: p[:[/][]] []\n" "\t r[maxactive][:[/][]] []\n" +#endif +#ifdef CONFIG_FPROBE_EVENTS + "\t f[:[/][]] [%return] []\n" + "\t t[:[/][]] []\n" +#endif #ifdef CONFIG_HIST_TRIGGERS "\t s:[synthetic/] []\n" #endif @@ -5691,7 +5698,11 @@ static const char readme_msg[] = "\t args: =fetcharg[:type]\n" "\t fetcharg: (%|$), @
, @[+|-],\n" #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API +#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS + "\t $stack, $stack, $retval, $comm, $arg, \n" +#else "\t $stack, $stack, $retval, $comm, $arg,\n" +#endif #else "\t $stack, $stack, $retval, $comm,\n" #endif diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index e6407a27d644..ed7906b13f09 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -148,6 +148,17 @@ struct kretprobe_trace_entry_head { unsigned long ret_ip; }; +struct fentry_trace_entry_head { + struct trace_entry ent; + unsigned long ip; +}; + +struct fexit_trace_entry_head { + struct trace_entry ent; + unsigned long func; + unsigned long ret_ip; +}; + #define TRACE_BUF_SIZE 1024 struct trace_array; diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index 67e854979d53..cb0077ba2b49 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -227,37 +227,6 @@ error: return ERR_PTR(ret); } -static int trace_eprobe_tp_arg_update(struct trace_eprobe *ep, int i) -{ - struct probe_arg *parg = &ep->tp.args[i]; - struct ftrace_event_field *field; - struct list_head *head; - int ret = -ENOENT; - - head = trace_get_fields(ep->event); - list_for_each_entry(field, head, link) { - if (!strcmp(parg->code->data, field->name)) { - kfree(parg->code->data); - parg->code->data = field; - return 0; - } - } - - /* - * Argument not found on event. But allow for comm and COMM - * to be used to get the current->comm. - */ - if (strcmp(parg->code->data, "COMM") == 0 || - strcmp(parg->code->data, "comm") == 0) { - parg->code->op = FETCH_OP_COMM; - ret = 0; - } - - kfree(parg->code->data); - parg->code->data = NULL; - return ret; -} - static int eprobe_event_define_fields(struct trace_event_call *event_call) { struct eprobe_trace_entry_head field; @@ -817,19 +786,16 @@ find_and_get_event(const char *system, const char *event_name) static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[], int i) { - unsigned int flags = TPARG_FL_KERNEL | TPARG_FL_TPOINT; + struct traceprobe_parse_context ctx = { + .event = ep->event, + .flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT, + }; int ret; - ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], flags); + ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], &ctx); if (ret) return ret; - if (ep->tp.args[i].code->op == FETCH_OP_TP_ARG) { - ret = trace_eprobe_tp_arg_update(ep, i); - if (ret) - trace_probe_log_err(0, BAD_ATTACH_ARG); - } - /* Handle symbols "@" */ if (!ret) ret = traceprobe_update_arg(&ep->tp.args[i]); diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c new file mode 100644 index 000000000000..dfe2e546acdc --- /dev/null +++ b/kernel/trace/trace_fprobe.c @@ -0,0 +1,1199 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Fprobe-based tracing events + * Copyright (C) 2022 Google LLC. + */ +#define pr_fmt(fmt) "trace_fprobe: " fmt + +#include +#include +#include +#include +#include +#include + +#include "trace_dynevent.h" +#include "trace_probe.h" +#include "trace_probe_kernel.h" +#include "trace_probe_tmpl.h" + +#define FPROBE_EVENT_SYSTEM "fprobes" +#define TRACEPOINT_EVENT_SYSTEM "tracepoints" +#define RETHOOK_MAXACTIVE_MAX 4096 + +static int trace_fprobe_create(const char *raw_command); +static int trace_fprobe_show(struct seq_file *m, struct dyn_event *ev); +static int trace_fprobe_release(struct dyn_event *ev); +static bool trace_fprobe_is_busy(struct dyn_event *ev); +static bool trace_fprobe_match(const char *system, const char *event, + int argc, const char **argv, struct dyn_event *ev); + +static struct dyn_event_operations trace_fprobe_ops = { + .create = trace_fprobe_create, + .show = trace_fprobe_show, + .is_busy = trace_fprobe_is_busy, + .free = trace_fprobe_release, + .match = trace_fprobe_match, +}; + +/* + * Fprobe event core functions + */ +struct trace_fprobe { + struct dyn_event devent; + struct fprobe fp; + const char *symbol; + struct tracepoint *tpoint; + struct module *mod; + struct trace_probe tp; +}; + +static bool is_trace_fprobe(struct dyn_event *ev) +{ + return ev->ops == &trace_fprobe_ops; +} + +static struct trace_fprobe *to_trace_fprobe(struct dyn_event *ev) +{ + return container_of(ev, struct trace_fprobe, devent); +} + +/** + * for_each_trace_fprobe - iterate over the trace_fprobe list + * @pos: the struct trace_fprobe * for each entry + * @dpos: the struct dyn_event * to use as a loop cursor + */ +#define for_each_trace_fprobe(pos, dpos) \ + for_each_dyn_event(dpos) \ + if (is_trace_fprobe(dpos) && (pos = to_trace_fprobe(dpos))) + +static bool trace_fprobe_is_return(struct trace_fprobe *tf) +{ + return tf->fp.exit_handler != NULL; +} + +static bool trace_fprobe_is_tracepoint(struct trace_fprobe *tf) +{ + return tf->tpoint != NULL; +} + +static const char *trace_fprobe_symbol(struct trace_fprobe *tf) +{ + return tf->symbol ? tf->symbol : "unknown"; +} + +static bool trace_fprobe_is_busy(struct dyn_event *ev) +{ + struct trace_fprobe *tf = to_trace_fprobe(ev); + + return trace_probe_is_enabled(&tf->tp); +} + +static bool trace_fprobe_match_command_head(struct trace_fprobe *tf, + int argc, const char **argv) +{ + char buf[MAX_ARGSTR_LEN + 1]; + + if (!argc) + return true; + + snprintf(buf, sizeof(buf), "%s", trace_fprobe_symbol(tf)); + if (strcmp(buf, argv[0])) + return false; + argc--; argv++; + + return trace_probe_match_command_args(&tf->tp, argc, argv); +} + +static bool trace_fprobe_match(const char *system, const char *event, + int argc, const char **argv, struct dyn_event *ev) +{ + struct trace_fprobe *tf = to_trace_fprobe(ev); + + if (event[0] != '\0' && strcmp(trace_probe_name(&tf->tp), event)) + return false; + + if (system && strcmp(trace_probe_group_name(&tf->tp), system)) + return false; + + return trace_fprobe_match_command_head(tf, argc, argv); +} + +static bool trace_fprobe_is_registered(struct trace_fprobe *tf) +{ + return fprobe_is_registered(&tf->fp); +} + +/* + * Note that we don't verify the fetch_insn code, since it does not come + * from user space. + */ +static int +process_fetch_insn(struct fetch_insn *code, void *rec, void *dest, + void *base) +{ + struct pt_regs *regs = rec; + unsigned long val; + int ret; + +retry: + /* 1st stage: get value from context */ + switch (code->op) { + case FETCH_OP_STACK: + val = regs_get_kernel_stack_nth(regs, code->param); + break; + case FETCH_OP_STACKP: + val = kernel_stack_pointer(regs); + break; + case FETCH_OP_RETVAL: + val = regs_return_value(regs); + break; +#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API + case FETCH_OP_ARG: + val = regs_get_kernel_argument(regs, code->param); + break; +#endif + case FETCH_NOP_SYMBOL: /* Ignore a place holder */ + code++; + goto retry; + default: + ret = process_common_fetch_insn(code, &val); + if (ret < 0) + return ret; + } + code++; + + return process_fetch_insn_bottom(code, val, dest, base); +} +NOKPROBE_SYMBOL(process_fetch_insn) + +/* function entry handler */ +static nokprobe_inline void +__fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, + struct pt_regs *regs, + struct trace_event_file *trace_file) +{ + struct fentry_trace_entry_head *entry; + struct trace_event_call *call = trace_probe_event_call(&tf->tp); + struct trace_event_buffer fbuffer; + int dsize; + + if (WARN_ON_ONCE(call != trace_file->event_call)) + return; + + if (trace_trigger_soft_disabled(trace_file)) + return; + + dsize = __get_data_size(&tf->tp, regs); + + entry = trace_event_buffer_reserve(&fbuffer, trace_file, + sizeof(*entry) + tf->tp.size + dsize); + if (!entry) + return; + + fbuffer.regs = regs; + entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); + entry->ip = entry_ip; + store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + + trace_event_buffer_commit(&fbuffer); +} + +static void +fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, + struct pt_regs *regs) +{ + struct event_file_link *link; + + trace_probe_for_each_link_rcu(link, &tf->tp) + __fentry_trace_func(tf, entry_ip, regs, link->file); +} +NOKPROBE_SYMBOL(fentry_trace_func); + +/* Kretprobe handler */ +static nokprobe_inline void +__fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, + unsigned long ret_ip, struct pt_regs *regs, + struct trace_event_file *trace_file) +{ + struct fexit_trace_entry_head *entry; + struct trace_event_buffer fbuffer; + struct trace_event_call *call = trace_probe_event_call(&tf->tp); + int dsize; + + if (WARN_ON_ONCE(call != trace_file->event_call)) + return; + + if (trace_trigger_soft_disabled(trace_file)) + return; + + dsize = __get_data_size(&tf->tp, regs); + + entry = trace_event_buffer_reserve(&fbuffer, trace_file, + sizeof(*entry) + tf->tp.size + dsize); + if (!entry) + return; + + fbuffer.regs = regs; + entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); + entry->func = entry_ip; + entry->ret_ip = ret_ip; + store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + + trace_event_buffer_commit(&fbuffer); +} + +static void +fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, + unsigned long ret_ip, struct pt_regs *regs) +{ + struct event_file_link *link; + + trace_probe_for_each_link_rcu(link, &tf->tp) + __fexit_trace_func(tf, entry_ip, ret_ip, regs, link->file); +} +NOKPROBE_SYMBOL(fexit_trace_func); + +#ifdef CONFIG_PERF_EVENTS + +static int fentry_perf_func(struct trace_fprobe *tf, unsigned long entry_ip, + struct pt_regs *regs) +{ + struct trace_event_call *call = trace_probe_event_call(&tf->tp); + struct fentry_trace_entry_head *entry; + struct hlist_head *head; + int size, __size, dsize; + int rctx; + + head = this_cpu_ptr(call->perf_events); + if (hlist_empty(head)) + return 0; + + dsize = __get_data_size(&tf->tp, regs); + __size = sizeof(*entry) + tf->tp.size + dsize; + size = ALIGN(__size + sizeof(u32), sizeof(u64)); + size -= sizeof(u32); + + entry = perf_trace_buf_alloc(size, NULL, &rctx); + if (!entry) + return 0; + + entry->ip = entry_ip; + memset(&entry[1], 0, dsize); + store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, + head, NULL); + return 0; +} +NOKPROBE_SYMBOL(fentry_perf_func); + +static void +fexit_perf_func(struct trace_fprobe *tf, unsigned long entry_ip, + unsigned long ret_ip, struct pt_regs *regs) +{ + struct trace_event_call *call = trace_probe_event_call(&tf->tp); + struct fexit_trace_entry_head *entry; + struct hlist_head *head; + int size, __size, dsize; + int rctx; + + head = this_cpu_ptr(call->perf_events); + if (hlist_empty(head)) + return; + + dsize = __get_data_size(&tf->tp, regs); + __size = sizeof(*entry) + tf->tp.size + dsize; + size = ALIGN(__size + sizeof(u32), sizeof(u64)); + size -= sizeof(u32); + + entry = perf_trace_buf_alloc(size, NULL, &rctx); + if (!entry) + return; + + entry->func = entry_ip; + entry->ret_ip = ret_ip; + store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, + head, NULL); +} +NOKPROBE_SYMBOL(fexit_perf_func); +#endif /* CONFIG_PERF_EVENTS */ + +static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip, + unsigned long ret_ip, struct pt_regs *regs, + void *entry_data) +{ + struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp); + int ret = 0; + + if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE)) + fentry_trace_func(tf, entry_ip, regs); +#ifdef CONFIG_PERF_EVENTS + if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE)) + ret = fentry_perf_func(tf, entry_ip, regs); +#endif + return ret; +} +NOKPROBE_SYMBOL(fentry_dispatcher); + +static void fexit_dispatcher(struct fprobe *fp, unsigned long entry_ip, + unsigned long ret_ip, struct pt_regs *regs, + void *entry_data) +{ + struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp); + + if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE)) + fexit_trace_func(tf, entry_ip, ret_ip, regs); +#ifdef CONFIG_PERF_EVENTS + if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE)) + fexit_perf_func(tf, entry_ip, ret_ip, regs); +#endif +} +NOKPROBE_SYMBOL(fexit_dispatcher); + +static void free_trace_fprobe(struct trace_fprobe *tf) +{ + if (tf) { + trace_probe_cleanup(&tf->tp); + kfree(tf->symbol); + kfree(tf); + } +} + +/* + * Allocate new trace_probe and initialize it (including fprobe). + */ +static struct trace_fprobe *alloc_trace_fprobe(const char *group, + const char *event, + const char *symbol, + struct tracepoint *tpoint, + int maxactive, + int nargs, bool is_return) +{ + struct trace_fprobe *tf; + int ret = -ENOMEM; + + tf = kzalloc(struct_size(tf, tp.args, nargs), GFP_KERNEL); + if (!tf) + return ERR_PTR(ret); + + tf->symbol = kstrdup(symbol, GFP_KERNEL); + if (!tf->symbol) + goto error; + + if (is_return) + tf->fp.exit_handler = fexit_dispatcher; + else + tf->fp.entry_handler = fentry_dispatcher; + + tf->tpoint = tpoint; + tf->fp.nr_maxactive = maxactive; + + ret = trace_probe_init(&tf->tp, event, group, false); + if (ret < 0) + goto error; + + dyn_event_init(&tf->devent, &trace_fprobe_ops); + return tf; +error: + free_trace_fprobe(tf); + return ERR_PTR(ret); +} + +static struct trace_fprobe *find_trace_fprobe(const char *event, + const char *group) +{ + struct dyn_event *pos; + struct trace_fprobe *tf; + + for_each_trace_fprobe(tf, pos) + if (strcmp(trace_probe_name(&tf->tp), event) == 0 && + strcmp(trace_probe_group_name(&tf->tp), group) == 0) + return tf; + return NULL; +} + +static inline int __enable_trace_fprobe(struct trace_fprobe *tf) +{ + if (trace_fprobe_is_registered(tf)) + enable_fprobe(&tf->fp); + + return 0; +} + +static void __disable_trace_fprobe(struct trace_probe *tp) +{ + struct trace_fprobe *tf; + + list_for_each_entry(tf, trace_probe_probe_list(tp), tp.list) { + if (!trace_fprobe_is_registered(tf)) + continue; + disable_fprobe(&tf->fp); + } +} + +/* + * Enable trace_probe + * if the file is NULL, enable "perf" handler, or enable "trace" handler. + */ +static int enable_trace_fprobe(struct trace_event_call *call, + struct trace_event_file *file) +{ + struct trace_probe *tp; + struct trace_fprobe *tf; + bool enabled; + int ret = 0; + + tp = trace_probe_primary_from_call(call); + if (WARN_ON_ONCE(!tp)) + return -ENODEV; + enabled = trace_probe_is_enabled(tp); + + /* This also changes "enabled" state */ + if (file) { + ret = trace_probe_add_file(tp, file); + if (ret) + return ret; + } else + trace_probe_set_flag(tp, TP_FLAG_PROFILE); + + if (!enabled) { + list_for_each_entry(tf, trace_probe_probe_list(tp), tp.list) { + /* TODO: check the fprobe is gone */ + __enable_trace_fprobe(tf); + } + } + + return 0; +} + +/* + * Disable trace_probe + * if the file is NULL, disable "perf" handler, or disable "trace" handler. + */ +static int disable_trace_fprobe(struct trace_event_call *call, + struct trace_event_file *file) +{ + struct trace_probe *tp; + + tp = trace_probe_primary_from_call(call); + if (WARN_ON_ONCE(!tp)) + return -ENODEV; + + if (file) { + if (!trace_probe_get_file_link(tp, file)) + return -ENOENT; + if (!trace_probe_has_single_file(tp)) + goto out; + trace_probe_clear_flag(tp, TP_FLAG_TRACE); + } else + trace_probe_clear_flag(tp, TP_FLAG_PROFILE); + + if (!trace_probe_is_enabled(tp)) + __disable_trace_fprobe(tp); + + out: + if (file) + /* + * Synchronization is done in below function. For perf event, + * file == NULL and perf_trace_event_unreg() calls + * tracepoint_synchronize_unregister() to ensure synchronize + * event. We don't need to care about it. + */ + trace_probe_remove_file(tp, file); + + return 0; +} + +/* Event entry printers */ +static enum print_line_t +print_fentry_event(struct trace_iterator *iter, int flags, + struct trace_event *event) +{ + struct fentry_trace_entry_head *field; + struct trace_seq *s = &iter->seq; + struct trace_probe *tp; + + field = (struct fentry_trace_entry_head *)iter->ent; + tp = trace_probe_primary_from_call( + container_of(event, struct trace_event_call, event)); + if (WARN_ON_ONCE(!tp)) + goto out; + + trace_seq_printf(s, "%s: (", trace_probe_name(tp)); + + if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) + goto out; + + trace_seq_putc(s, ')'); + + if (trace_probe_print_args(s, tp->args, tp->nr_args, + (u8 *)&field[1], field) < 0) + goto out; + + trace_seq_putc(s, '\n'); + out: + return trace_handle_return(s); +} + +static enum print_line_t +print_fexit_event(struct trace_iterator *iter, int flags, + struct trace_event *event) +{ + struct fexit_trace_entry_head *field; + struct trace_seq *s = &iter->seq; + struct trace_probe *tp; + + field = (struct fexit_trace_entry_head *)iter->ent; + tp = trace_probe_primary_from_call( + container_of(event, struct trace_event_call, event)); + if (WARN_ON_ONCE(!tp)) + goto out; + + trace_seq_printf(s, "%s: (", trace_probe_name(tp)); + + if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) + goto out; + + trace_seq_puts(s, " <- "); + + if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) + goto out; + + trace_seq_putc(s, ')'); + + if (trace_probe_print_args(s, tp->args, tp->nr_args, + (u8 *)&field[1], field) < 0) + goto out; + + trace_seq_putc(s, '\n'); + + out: + return trace_handle_return(s); +} + +static int fentry_event_define_fields(struct trace_event_call *event_call) +{ + int ret; + struct fentry_trace_entry_head field; + struct trace_probe *tp; + + tp = trace_probe_primary_from_call(event_call); + if (WARN_ON_ONCE(!tp)) + return -ENOENT; + + DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); + + return traceprobe_define_arg_fields(event_call, sizeof(field), tp); +} + +static int fexit_event_define_fields(struct trace_event_call *event_call) +{ + int ret; + struct fexit_trace_entry_head field; + struct trace_probe *tp; + + tp = trace_probe_primary_from_call(event_call); + if (WARN_ON_ONCE(!tp)) + return -ENOENT; + + DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); + DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); + + return traceprobe_define_arg_fields(event_call, sizeof(field), tp); +} + +static struct trace_event_functions fentry_funcs = { + .trace = print_fentry_event +}; + +static struct trace_event_functions fexit_funcs = { + .trace = print_fexit_event +}; + +static struct trace_event_fields fentry_fields_array[] = { + { .type = TRACE_FUNCTION_TYPE, + .define_fields = fentry_event_define_fields }, + {} +}; + +static struct trace_event_fields fexit_fields_array[] = { + { .type = TRACE_FUNCTION_TYPE, + .define_fields = fexit_event_define_fields }, + {} +}; + +static int fprobe_register(struct trace_event_call *event, + enum trace_reg type, void *data); + +static inline void init_trace_event_call(struct trace_fprobe *tf) +{ + struct trace_event_call *call = trace_probe_event_call(&tf->tp); + + if (trace_fprobe_is_return(tf)) { + call->event.funcs = &fexit_funcs; + call->class->fields_array = fexit_fields_array; + } else { + call->event.funcs = &fentry_funcs; + call->class->fields_array = fentry_fields_array; + } + + call->flags = TRACE_EVENT_FL_FPROBE; + call->class->reg = fprobe_register; +} + +static int register_fprobe_event(struct trace_fprobe *tf) +{ + init_trace_event_call(tf); + + return trace_probe_register_event_call(&tf->tp); +} + +static int unregister_fprobe_event(struct trace_fprobe *tf) +{ + return trace_probe_unregister_event_call(&tf->tp); +} + +/* Internal register function - just handle fprobe and flags */ +static int __register_trace_fprobe(struct trace_fprobe *tf) +{ + int i, ret; + + /* Should we need new LOCKDOWN flag for fprobe? */ + ret = security_locked_down(LOCKDOWN_KPROBES); + if (ret) + return ret; + + if (trace_fprobe_is_registered(tf)) + return -EINVAL; + + for (i = 0; i < tf->tp.nr_args; i++) { + ret = traceprobe_update_arg(&tf->tp.args[i]); + if (ret) + return ret; + } + + /* Set/clear disabled flag according to tp->flag */ + if (trace_probe_is_enabled(&tf->tp)) + tf->fp.flags &= ~FPROBE_FL_DISABLED; + else + tf->fp.flags |= FPROBE_FL_DISABLED; + + if (trace_fprobe_is_tracepoint(tf)) { + struct tracepoint *tpoint = tf->tpoint; + unsigned long ip = (unsigned long)tpoint->probestub; + /* + * Here, we do 2 steps to enable fprobe on a tracepoint. + * At first, put __probestub_##TP function on the tracepoint + * and put a fprobe on the stub function. + */ + ret = tracepoint_probe_register_prio_may_exist(tpoint, + tpoint->probestub, NULL, 0); + if (ret < 0) + return ret; + return register_fprobe_ips(&tf->fp, &ip, 1); + } + + /* TODO: handle filter, nofilter or symbol list */ + return register_fprobe(&tf->fp, tf->symbol, NULL); +} + +/* Internal unregister function - just handle fprobe and flags */ +static void __unregister_trace_fprobe(struct trace_fprobe *tf) +{ + if (trace_fprobe_is_registered(tf)) { + unregister_fprobe(&tf->fp); + memset(&tf->fp, 0, sizeof(tf->fp)); + if (trace_fprobe_is_tracepoint(tf)) { + tracepoint_probe_unregister(tf->tpoint, + tf->tpoint->probestub, NULL); + tf->tpoint = NULL; + tf->mod = NULL; + } + } +} + +/* TODO: make this trace_*probe common function */ +/* Unregister a trace_probe and probe_event */ +static int unregister_trace_fprobe(struct trace_fprobe *tf) +{ + /* If other probes are on the event, just unregister fprobe */ + if (trace_probe_has_sibling(&tf->tp)) + goto unreg; + + /* Enabled event can not be unregistered */ + if (trace_probe_is_enabled(&tf->tp)) + return -EBUSY; + + /* If there's a reference to the dynamic event */ + if (trace_event_dyn_busy(trace_probe_event_call(&tf->tp))) + return -EBUSY; + + /* Will fail if probe is being used by ftrace or perf */ + if (unregister_fprobe_event(tf)) + return -EBUSY; + +unreg: + __unregister_trace_fprobe(tf); + dyn_event_remove(&tf->devent); + trace_probe_unlink(&tf->tp); + + return 0; +} + +static bool trace_fprobe_has_same_fprobe(struct trace_fprobe *orig, + struct trace_fprobe *comp) +{ + struct trace_probe_event *tpe = orig->tp.event; + int i; + + list_for_each_entry(orig, &tpe->probes, tp.list) { + if (strcmp(trace_fprobe_symbol(orig), + trace_fprobe_symbol(comp))) + continue; + + /* + * trace_probe_compare_arg_type() ensured that nr_args and + * each argument name and type are same. Let's compare comm. + */ + for (i = 0; i < orig->tp.nr_args; i++) { + if (strcmp(orig->tp.args[i].comm, + comp->tp.args[i].comm)) + break; + } + + if (i == orig->tp.nr_args) + return true; + } + + return false; +} + +static int append_trace_fprobe(struct trace_fprobe *tf, struct trace_fprobe *to) +{ + int ret; + + if (trace_fprobe_is_return(tf) != trace_fprobe_is_return(to) || + trace_fprobe_is_tracepoint(tf) != trace_fprobe_is_tracepoint(to)) { + trace_probe_log_set_index(0); + trace_probe_log_err(0, DIFF_PROBE_TYPE); + return -EEXIST; + } + ret = trace_probe_compare_arg_type(&tf->tp, &to->tp); + if (ret) { + /* Note that argument starts index = 2 */ + trace_probe_log_set_index(ret + 1); + trace_probe_log_err(0, DIFF_ARG_TYPE); + return -EEXIST; + } + if (trace_fprobe_has_same_fprobe(to, tf)) { + trace_probe_log_set_index(0); + trace_probe_log_err(0, SAME_PROBE); + return -EEXIST; + } + + /* Append to existing event */ + ret = trace_probe_append(&tf->tp, &to->tp); + if (ret) + return ret; + + ret = __register_trace_fprobe(tf); + if (ret) + trace_probe_unlink(&tf->tp); + else + dyn_event_add(&tf->devent, trace_probe_event_call(&tf->tp)); + + return ret; +} + +/* Register a trace_probe and probe_event */ +static int register_trace_fprobe(struct trace_fprobe *tf) +{ + struct trace_fprobe *old_tf; + int ret; + + mutex_lock(&event_mutex); + + old_tf = find_trace_fprobe(trace_probe_name(&tf->tp), + trace_probe_group_name(&tf->tp)); + if (old_tf) { + ret = append_trace_fprobe(tf, old_tf); + goto end; + } + + /* Register new event */ + ret = register_fprobe_event(tf); + if (ret) { + if (ret == -EEXIST) { + trace_probe_log_set_index(0); + trace_probe_log_err(0, EVENT_EXIST); + } else + pr_warn("Failed to register probe event(%d)\n", ret); + goto end; + } + + /* Register fprobe */ + ret = __register_trace_fprobe(tf); + if (ret < 0) + unregister_fprobe_event(tf); + else + dyn_event_add(&tf->devent, trace_probe_event_call(&tf->tp)); + +end: + mutex_unlock(&event_mutex); + return ret; +} + +#ifdef CONFIG_MODULES +static int __tracepoint_probe_module_cb(struct notifier_block *self, + unsigned long val, void *data) +{ + struct tp_module *tp_mod = data; + struct trace_fprobe *tf; + struct dyn_event *pos; + + if (val != MODULE_STATE_GOING) + return NOTIFY_DONE; + + mutex_lock(&event_mutex); + for_each_trace_fprobe(tf, pos) { + if (tp_mod->mod == tf->mod) { + tracepoint_probe_unregister(tf->tpoint, + tf->tpoint->probestub, NULL); + tf->tpoint = NULL; + tf->mod = NULL; + } + } + mutex_unlock(&event_mutex); + + return NOTIFY_DONE; +} + +static struct notifier_block tracepoint_module_nb = { + .notifier_call = __tracepoint_probe_module_cb, +}; +#endif /* CONFIG_MODULES */ + +struct __find_tracepoint_cb_data { + const char *tp_name; + struct tracepoint *tpoint; +}; + +static void __find_tracepoint_cb(struct tracepoint *tp, void *priv) +{ + struct __find_tracepoint_cb_data *data = priv; + + if (!data->tpoint && !strcmp(data->tp_name, tp->name)) + data->tpoint = tp; +} + +static struct tracepoint *find_tracepoint(const char *tp_name) +{ + struct __find_tracepoint_cb_data data = { + .tp_name = tp_name, + }; + + for_each_kernel_tracepoint(__find_tracepoint_cb, &data); + + return data.tpoint; +} + +static int __trace_fprobe_create(int argc, const char *argv[]) +{ + /* + * Argument syntax: + * - Add fentry probe: + * f[:[GRP/][EVENT]] [MOD:]KSYM [FETCHARGS] + * - Add fexit probe: + * f[N][:[GRP/][EVENT]] [MOD:]KSYM%return [FETCHARGS] + * - Add tracepoint probe: + * t[:[GRP/][EVENT]] TRACEPOINT [FETCHARGS] + * + * Fetch args: + * $retval : fetch return value + * $stack : fetch stack address + * $stackN : fetch Nth entry of stack (N:0-) + * $argN : fetch Nth argument (N:1-) + * $comm : fetch current task comm + * @ADDR : fetch memory at ADDR (ADDR should be in kernel) + * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) + * Dereferencing memory fetch: + * +|-offs(ARG) : fetch memory at ARG +|- offs address. + * Alias name of args: + * NAME=FETCHARG : set NAME as alias of FETCHARG. + * Type of args: + * FETCHARG:TYPE : use TYPE instead of unsigned long. + */ + struct trace_fprobe *tf = NULL; + int i, len, new_argc = 0, ret = 0; + bool is_return = false; + char *symbol = NULL, *tmp = NULL; + const char *event = NULL, *group = FPROBE_EVENT_SYSTEM; + const char **new_argv = NULL; + int maxactive = 0; + char buf[MAX_EVENT_NAME_LEN]; + char gbuf[MAX_EVENT_NAME_LEN]; + char sbuf[KSYM_NAME_LEN]; + char abuf[MAX_BTF_ARGS_LEN]; + bool is_tracepoint = false; + struct tracepoint *tpoint = NULL; + struct traceprobe_parse_context ctx = { + .flags = TPARG_FL_KERNEL | TPARG_FL_FPROBE, + }; + + if ((argv[0][0] != 'f' && argv[0][0] != 't') || argc < 2) + return -ECANCELED; + + if (argv[0][0] == 't') { + is_tracepoint = true; + group = TRACEPOINT_EVENT_SYSTEM; + } + + trace_probe_log_init("trace_fprobe", argc, argv); + + event = strchr(&argv[0][1], ':'); + if (event) + event++; + + if (isdigit(argv[0][1])) { + if (event) + len = event - &argv[0][1] - 1; + else + len = strlen(&argv[0][1]); + if (len > MAX_EVENT_NAME_LEN - 1) { + trace_probe_log_err(1, BAD_MAXACT); + goto parse_error; + } + memcpy(buf, &argv[0][1], len); + buf[len] = '\0'; + ret = kstrtouint(buf, 0, &maxactive); + if (ret || !maxactive) { + trace_probe_log_err(1, BAD_MAXACT); + goto parse_error; + } + /* fprobe rethook instances are iterated over via a list. The + * maximum should stay reasonable. + */ + if (maxactive > RETHOOK_MAXACTIVE_MAX) { + trace_probe_log_err(1, MAXACT_TOO_BIG); + goto parse_error; + } + } + + trace_probe_log_set_index(1); + + /* a symbol(or tracepoint) must be specified */ + symbol = kstrdup(argv[1], GFP_KERNEL); + if (!symbol) + return -ENOMEM; + + tmp = strchr(symbol, '%'); + if (tmp) { + if (!is_tracepoint && !strcmp(tmp, "%return")) { + *tmp = '\0'; + is_return = true; + } else { + trace_probe_log_err(tmp - symbol, BAD_ADDR_SUFFIX); + goto parse_error; + } + } + if (!is_return && maxactive) { + trace_probe_log_set_index(0); + trace_probe_log_err(1, BAD_MAXACT_TYPE); + goto parse_error; + } + + trace_probe_log_set_index(0); + if (event) { + ret = traceprobe_parse_event_name(&event, &group, gbuf, + event - argv[0]); + if (ret) + goto parse_error; + } + + if (!event) { + /* Make a new event name */ + if (is_tracepoint) + snprintf(buf, MAX_EVENT_NAME_LEN, "%s%s", + isdigit(*symbol) ? "_" : "", symbol); + else + snprintf(buf, MAX_EVENT_NAME_LEN, "%s__%s", symbol, + is_return ? "exit" : "entry"); + sanitize_event_name(buf); + event = buf; + } + + if (is_return) + ctx.flags |= TPARG_FL_RETURN; + else + ctx.flags |= TPARG_FL_FENTRY; + + if (is_tracepoint) { + ctx.flags |= TPARG_FL_TPOINT; + tpoint = find_tracepoint(symbol); + if (!tpoint) { + trace_probe_log_set_index(1); + trace_probe_log_err(0, NO_TRACEPOINT); + goto parse_error; + } + ctx.funcname = kallsyms_lookup( + (unsigned long)tpoint->probestub, + NULL, NULL, NULL, sbuf); + } else + ctx.funcname = symbol; + + argc -= 2; argv += 2; + new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc, + abuf, MAX_BTF_ARGS_LEN, &ctx); + if (IS_ERR(new_argv)) { + ret = PTR_ERR(new_argv); + new_argv = NULL; + goto out; + } + if (new_argv) { + argc = new_argc; + argv = new_argv; + } + + /* setup a probe */ + tf = alloc_trace_fprobe(group, event, symbol, tpoint, maxactive, + argc, is_return); + if (IS_ERR(tf)) { + ret = PTR_ERR(tf); + /* This must return -ENOMEM, else there is a bug */ + WARN_ON_ONCE(ret != -ENOMEM); + goto out; /* We know tf is not allocated */ + } + + if (is_tracepoint) + tf->mod = __module_text_address( + (unsigned long)tf->tpoint->probestub); + + /* parse arguments */ + for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + trace_probe_log_set_index(i + 2); + ctx.offset = 0; + ret = traceprobe_parse_probe_arg(&tf->tp, i, argv[i], &ctx); + if (ret) + goto error; /* This can be -ENOMEM */ + } + + ret = traceprobe_set_print_fmt(&tf->tp, + is_return ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL); + if (ret < 0) + goto error; + + ret = register_trace_fprobe(tf); + if (ret) { + trace_probe_log_set_index(1); + if (ret == -EILSEQ) + trace_probe_log_err(0, BAD_INSN_BNDRY); + else if (ret == -ENOENT) + trace_probe_log_err(0, BAD_PROBE_ADDR); + else if (ret != -ENOMEM && ret != -EEXIST) + trace_probe_log_err(0, FAIL_REG_PROBE); + goto error; + } + +out: + trace_probe_log_clear(); + kfree(new_argv); + kfree(symbol); + return ret; + +parse_error: + ret = -EINVAL; +error: + free_trace_fprobe(tf); + goto out; +} + +static int trace_fprobe_create(const char *raw_command) +{ + return trace_probe_create(raw_command, __trace_fprobe_create); +} + +static int trace_fprobe_release(struct dyn_event *ev) +{ + struct trace_fprobe *tf = to_trace_fprobe(ev); + int ret = unregister_trace_fprobe(tf); + + if (!ret) + free_trace_fprobe(tf); + return ret; +} + +static int trace_fprobe_show(struct seq_file *m, struct dyn_event *ev) +{ + struct trace_fprobe *tf = to_trace_fprobe(ev); + int i; + + if (trace_fprobe_is_tracepoint(tf)) + seq_putc(m, 't'); + else + seq_putc(m, 'f'); + if (trace_fprobe_is_return(tf) && tf->fp.nr_maxactive) + seq_printf(m, "%d", tf->fp.nr_maxactive); + seq_printf(m, ":%s/%s", trace_probe_group_name(&tf->tp), + trace_probe_name(&tf->tp)); + + seq_printf(m, " %s%s", trace_fprobe_symbol(tf), + trace_fprobe_is_return(tf) ? "%return" : ""); + + for (i = 0; i < tf->tp.nr_args; i++) + seq_printf(m, " %s=%s", tf->tp.args[i].name, tf->tp.args[i].comm); + seq_putc(m, '\n'); + + return 0; +} + +/* + * called by perf_trace_init() or __ftrace_set_clr_event() under event_mutex. + */ +static int fprobe_register(struct trace_event_call *event, + enum trace_reg type, void *data) +{ + struct trace_event_file *file = data; + + switch (type) { + case TRACE_REG_REGISTER: + return enable_trace_fprobe(event, file); + case TRACE_REG_UNREGISTER: + return disable_trace_fprobe(event, file); + +#ifdef CONFIG_PERF_EVENTS + case TRACE_REG_PERF_REGISTER: + return enable_trace_fprobe(event, NULL); + case TRACE_REG_PERF_UNREGISTER: + return disable_trace_fprobe(event, NULL); + case TRACE_REG_PERF_OPEN: + case TRACE_REG_PERF_CLOSE: + case TRACE_REG_PERF_ADD: + case TRACE_REG_PERF_DEL: + return 0; +#endif + } + return 0; +} + +/* + * Register dynevent at core_initcall. This allows kernel to setup fprobe + * events in postcore_initcall without tracefs. + */ +static __init int init_fprobe_trace_early(void) +{ + int ret; + + ret = dyn_event_register(&trace_fprobe_ops); + if (ret) + return ret; + +#ifdef CONFIG_MODULES + ret = register_tracepoint_module_notifier(&tracepoint_module_nb); + if (ret) + return ret; +#endif + + return 0; +} +core_initcall(init_fprobe_trace_early); diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 1b3fa7b854aa..23dba01831f7 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -732,9 +732,10 @@ static int __trace_kprobe_create(int argc, const char *argv[]) * FETCHARG:TYPE : use TYPE instead of unsigned long. */ struct trace_kprobe *tk = NULL; - int i, len, ret = 0; + int i, len, new_argc = 0, ret = 0; bool is_return = false; char *symbol = NULL, *tmp = NULL; + const char **new_argv = NULL; const char *event = NULL, *group = KPROBE_EVENT_SYSTEM; enum probe_print_type ptype; int maxactive = 0; @@ -742,7 +743,8 @@ static int __trace_kprobe_create(int argc, const char *argv[]) void *addr = NULL; char buf[MAX_EVENT_NAME_LEN]; char gbuf[MAX_EVENT_NAME_LEN]; - unsigned int flags = TPARG_FL_KERNEL; + char abuf[MAX_BTF_ARGS_LEN]; + struct traceprobe_parse_context ctx = { .flags = TPARG_FL_KERNEL }; switch (argv[0][0]) { case 'r': @@ -764,7 +766,7 @@ static int __trace_kprobe_create(int argc, const char *argv[]) if (isdigit(argv[0][1])) { if (!is_return) { - trace_probe_log_err(1, MAXACT_NO_KPROBE); + trace_probe_log_err(1, BAD_MAXACT_TYPE); goto parse_error; } if (event) @@ -823,10 +825,10 @@ static int __trace_kprobe_create(int argc, const char *argv[]) goto parse_error; } if (is_return) - flags |= TPARG_FL_RETURN; + ctx.flags |= TPARG_FL_RETURN; ret = kprobe_on_func_entry(NULL, symbol, offset); - if (ret == 0) - flags |= TPARG_FL_FENTRY; + if (ret == 0 && !is_return) + ctx.flags |= TPARG_FL_FENTRY; /* Defer the ENOENT case until register kprobe */ if (ret == -EINVAL && is_return) { trace_probe_log_err(0, BAD_RETPROBE); @@ -854,21 +856,35 @@ static int __trace_kprobe_create(int argc, const char *argv[]) event = buf; } + argc -= 2; argv += 2; + ctx.funcname = symbol; + new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc, + abuf, MAX_BTF_ARGS_LEN, &ctx); + if (IS_ERR(new_argv)) { + ret = PTR_ERR(new_argv); + new_argv = NULL; + goto out; + } + if (new_argv) { + argc = new_argc; + argv = new_argv; + } + /* setup a probe */ tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive, - argc - 2, is_return); + argc, is_return); if (IS_ERR(tk)) { ret = PTR_ERR(tk); /* This must return -ENOMEM, else there is a bug */ WARN_ON_ONCE(ret != -ENOMEM); goto out; /* We know tk is not allocated */ } - argc -= 2; argv += 2; /* parse arguments */ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { trace_probe_log_set_index(i + 2); - ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], flags); + ctx.offset = 0; + ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], &ctx); if (ret) goto error; /* This can be -ENOMEM */ } @@ -892,6 +908,7 @@ static int __trace_kprobe_create(int argc, const char *argv[]) out: trace_probe_log_clear(); + kfree(new_argv); kfree(symbol); return ret; diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 73055ba8d8ef..7ba371da0926 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -11,6 +11,8 @@ */ #define pr_fmt(fmt) "trace_probe: " fmt +#include + #include "trace_probe.h" #undef C @@ -283,69 +285,354 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup, return 0; } +static int parse_trace_event_arg(char *arg, struct fetch_insn *code, + struct traceprobe_parse_context *ctx) +{ + struct ftrace_event_field *field; + struct list_head *head; + + head = trace_get_fields(ctx->event); + list_for_each_entry(field, head, link) { + if (!strcmp(arg, field->name)) { + code->op = FETCH_OP_TP_ARG; + code->data = field; + return 0; + } + } + return -ENOENT; +} + +#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS + +static struct btf *traceprobe_get_btf(void) +{ + struct btf *btf = bpf_get_btf_vmlinux(); + + if (IS_ERR_OR_NULL(btf)) + return NULL; + + return btf; +} + +static u32 btf_type_int(const struct btf_type *t) +{ + return *(u32 *)(t + 1); +} + +static const char *type_from_btf_id(struct btf *btf, s32 id) +{ + const struct btf_type *t; + u32 intdata; + s32 tid; + + /* TODO: const char * could be converted as a string */ + t = btf_type_skip_modifiers(btf, id, &tid); + + switch (BTF_INFO_KIND(t->info)) { + case BTF_KIND_ENUM: + /* enum is "int", so convert to "s32" */ + return "s32"; + case BTF_KIND_ENUM64: + return "s64"; + case BTF_KIND_PTR: + /* pointer will be converted to "x??" */ + if (IS_ENABLED(CONFIG_64BIT)) + return "x64"; + else + return "x32"; + case BTF_KIND_INT: + intdata = btf_type_int(t); + if (BTF_INT_ENCODING(intdata) & BTF_INT_SIGNED) { + switch (BTF_INT_BITS(intdata)) { + case 8: + return "s8"; + case 16: + return "s16"; + case 32: + return "s32"; + case 64: + return "s64"; + } + } else { /* unsigned */ + switch (BTF_INT_BITS(intdata)) { + case 8: + return "u8"; + case 16: + return "u16"; + case 32: + return "u32"; + case 64: + return "u64"; + } + } + } + /* TODO: support other types */ + + return NULL; +} + +static const struct btf_type *find_btf_func_proto(const char *funcname) +{ + struct btf *btf = traceprobe_get_btf(); + const struct btf_type *t; + s32 id; + + if (!btf || !funcname) + return ERR_PTR(-EINVAL); + + id = btf_find_by_name_kind(btf, funcname, BTF_KIND_FUNC); + if (id <= 0) + return ERR_PTR(-ENOENT); + + /* Get BTF_KIND_FUNC type */ + t = btf_type_by_id(btf, id); + if (!btf_type_is_func(t)) + return ERR_PTR(-ENOENT); + + /* The type of BTF_KIND_FUNC is BTF_KIND_FUNC_PROTO */ + t = btf_type_by_id(btf, t->type); + if (!btf_type_is_func_proto(t)) + return ERR_PTR(-ENOENT); + + return t; +} + +static const struct btf_param *find_btf_func_param(const char *funcname, s32 *nr, + bool tracepoint) +{ + const struct btf_param *param; + const struct btf_type *t; + + if (!funcname || !nr) + return ERR_PTR(-EINVAL); + + t = find_btf_func_proto(funcname); + if (IS_ERR(t)) + return (const struct btf_param *)t; + + *nr = btf_type_vlen(t); + param = (const struct btf_param *)(t + 1); + + /* Hide the first 'data' argument of tracepoint */ + if (tracepoint) { + (*nr)--; + param++; + } + + if (*nr > 0) + return param; + else + return NULL; +} + +static int parse_btf_arg(const char *varname, struct fetch_insn *code, + struct traceprobe_parse_context *ctx) +{ + struct btf *btf = traceprobe_get_btf(); + const struct btf_param *params; + int i; + + if (!btf) { + trace_probe_log_err(ctx->offset, NOSUP_BTFARG); + return -EOPNOTSUPP; + } + + if (WARN_ON_ONCE(!ctx->funcname)) + return -EINVAL; + + if (!ctx->params) { + params = find_btf_func_param(ctx->funcname, &ctx->nr_params, + ctx->flags & TPARG_FL_TPOINT); + if (IS_ERR(params)) { + trace_probe_log_err(ctx->offset, NO_BTF_ENTRY); + return PTR_ERR(params); + } + ctx->params = params; + } else + params = ctx->params; + + for (i = 0; i < ctx->nr_params; i++) { + const char *name = btf_name_by_offset(btf, params[i].name_off); + + if (name && !strcmp(name, varname)) { + code->op = FETCH_OP_ARG; + if (ctx->flags & TPARG_FL_TPOINT) + code->param = i + 1; + else + code->param = i; + return 0; + } + } + trace_probe_log_err(ctx->offset, NO_BTFARG); + return -ENOENT; +} + +static const struct fetch_type *parse_btf_arg_type(int arg_idx, + struct traceprobe_parse_context *ctx) +{ + struct btf *btf = traceprobe_get_btf(); + const char *typestr = NULL; + + if (btf && ctx->params) { + if (ctx->flags & TPARG_FL_TPOINT) + arg_idx--; + typestr = type_from_btf_id(btf, ctx->params[arg_idx].type); + } + + return find_fetch_type(typestr, ctx->flags); +} + +static const struct fetch_type *parse_btf_retval_type( + struct traceprobe_parse_context *ctx) +{ + struct btf *btf = traceprobe_get_btf(); + const char *typestr = NULL; + const struct btf_type *t; + + if (btf && ctx->funcname) { + t = find_btf_func_proto(ctx->funcname); + if (!IS_ERR(t)) + typestr = type_from_btf_id(btf, t->type); + } + + return find_fetch_type(typestr, ctx->flags); +} + +static bool is_btf_retval_void(const char *funcname) +{ + const struct btf_type *t; + + t = find_btf_func_proto(funcname); + if (IS_ERR(t)) + return false; + + return t->type == 0; +} +#else +static struct btf *traceprobe_get_btf(void) +{ + return NULL; +} + +static const struct btf_param *find_btf_func_param(const char *funcname, s32 *nr, + bool tracepoint) +{ + return ERR_PTR(-EOPNOTSUPP); +} + +static int parse_btf_arg(const char *varname, struct fetch_insn *code, + struct traceprobe_parse_context *ctx) +{ + trace_probe_log_err(ctx->offset, NOSUP_BTFARG); + return -EOPNOTSUPP; +} + +#define parse_btf_arg_type(idx, ctx) \ + find_fetch_type(NULL, ctx->flags) + +#define parse_btf_retval_type(ctx) \ + find_fetch_type(NULL, ctx->flags) + +#define is_btf_retval_void(funcname) (false) + +#endif + #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) static int parse_probe_vars(char *arg, const struct fetch_type *t, - struct fetch_insn *code, unsigned int flags, int offs) + struct fetch_insn *code, + struct traceprobe_parse_context *ctx) { unsigned long param; + int err = TP_ERR_BAD_VAR; int ret = 0; int len; - if (flags & TPARG_FL_TPOINT) { + if (ctx->flags & TPARG_FL_TEVENT) { if (code->data) return -EFAULT; - code->data = kstrdup(arg, GFP_KERNEL); - if (!code->data) - return -ENOMEM; - code->op = FETCH_OP_TP_ARG; - } else if (strcmp(arg, "retval") == 0) { - if (flags & TPARG_FL_RETURN) { - code->op = FETCH_OP_RETVAL; - } else { - trace_probe_log_err(offs, RETVAL_ON_PROBE); - ret = -EINVAL; + ret = parse_trace_event_arg(arg, code, ctx); + if (!ret) + return 0; + if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) { + code->op = FETCH_OP_COMM; + return 0; } - } else if ((len = str_has_prefix(arg, "stack"))) { + /* backward compatibility */ + ctx->offset = 0; + goto inval; + } + + if (strcmp(arg, "retval") == 0) { + if (ctx->flags & TPARG_FL_RETURN) { + if ((ctx->flags & TPARG_FL_KERNEL) && + is_btf_retval_void(ctx->funcname)) { + err = TP_ERR_NO_RETVAL; + goto inval; + } + code->op = FETCH_OP_RETVAL; + return 0; + } + err = TP_ERR_RETVAL_ON_PROBE; + goto inval; + } + + len = str_has_prefix(arg, "stack"); + if (len) { + if (arg[len] == '\0') { code->op = FETCH_OP_STACKP; - } else if (isdigit(arg[len])) { - ret = kstrtoul(arg + len, 10, ¶m); - if (ret) { - goto inval_var; - } else if ((flags & TPARG_FL_KERNEL) && - param > PARAM_MAX_STACK) { - trace_probe_log_err(offs, BAD_STACK_NUM); - ret = -EINVAL; - } else { - code->op = FETCH_OP_STACK; - code->param = (unsigned int)param; - } - } else - goto inval_var; - } else if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) { - code->op = FETCH_OP_COMM; -#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API - } else if (((flags & TPARG_FL_MASK) == - (TPARG_FL_KERNEL | TPARG_FL_FENTRY)) && - (len = str_has_prefix(arg, "arg"))) { - ret = kstrtoul(arg + len, 10, ¶m); - if (ret) { - goto inval_var; - } else if (!param || param > PARAM_MAX_STACK) { - trace_probe_log_err(offs, BAD_ARG_NUM); - return -EINVAL; + return 0; } + + if (isdigit(arg[len])) { + ret = kstrtoul(arg + len, 10, ¶m); + if (ret) + goto inval; + + if ((ctx->flags & TPARG_FL_KERNEL) && + param > PARAM_MAX_STACK) { + err = TP_ERR_BAD_STACK_NUM; + goto inval; + } + code->op = FETCH_OP_STACK; + code->param = (unsigned int)param; + return 0; + } + goto inval; + } + + if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) { + code->op = FETCH_OP_COMM; + return 0; + } + +#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API + len = str_has_prefix(arg, "arg"); + if (len && tparg_is_function_entry(ctx->flags)) { + ret = kstrtoul(arg + len, 10, ¶m); + if (ret) + goto inval; + + if (!param || param > PARAM_MAX_STACK) { + err = TP_ERR_BAD_ARG_NUM; + goto inval; + } + code->op = FETCH_OP_ARG; code->param = (unsigned int)param - 1; + /* + * The tracepoint probe will probe a stub function, and the + * first parameter of the stub is a dummy and should be ignored. + */ + if (ctx->flags & TPARG_FL_TPOINT) + code->param++; + return 0; + } #endif - } else - goto inval_var; - return ret; - -inval_var: - trace_probe_log_err(offs, BAD_VAR); +inval: + __trace_probe_log_err(ctx->offset, err); return -EINVAL; } @@ -378,7 +665,7 @@ static int __parse_imm_string(char *str, char **pbuf, int offs) static int parse_probe_arg(char *arg, const struct fetch_type *type, struct fetch_insn **pcode, struct fetch_insn *end, - unsigned int flags, int offs) + struct traceprobe_parse_context *ctx) { struct fetch_insn *code = *pcode; unsigned long param; @@ -389,13 +676,13 @@ parse_probe_arg(char *arg, const struct fetch_type *type, switch (arg[0]) { case '$': - ret = parse_probe_vars(arg + 1, type, code, flags, offs); + ret = parse_probe_vars(arg + 1, type, code, ctx); break; case '%': /* named register */ - if (flags & TPARG_FL_TPOINT) { - /* eprobes do not handle registers */ - trace_probe_log_err(offs, BAD_VAR); + if (ctx->flags & (TPARG_FL_TEVENT | TPARG_FL_FPROBE)) { + /* eprobe and fprobe do not handle registers */ + trace_probe_log_err(ctx->offset, BAD_VAR); break; } ret = regs_query_register_offset(arg + 1); @@ -404,14 +691,14 @@ parse_probe_arg(char *arg, const struct fetch_type *type, code->param = (unsigned int)ret; ret = 0; } else - trace_probe_log_err(offs, BAD_REG_NAME); + trace_probe_log_err(ctx->offset, BAD_REG_NAME); break; case '@': /* memory, file-offset or symbol */ if (isdigit(arg[1])) { ret = kstrtoul(arg + 1, 0, ¶m); if (ret) { - trace_probe_log_err(offs, BAD_MEM_ADDR); + trace_probe_log_err(ctx->offset, BAD_MEM_ADDR); break; } /* load address */ @@ -419,13 +706,13 @@ parse_probe_arg(char *arg, const struct fetch_type *type, code->immediate = param; } else if (arg[1] == '+') { /* kprobes don't support file offsets */ - if (flags & TPARG_FL_KERNEL) { - trace_probe_log_err(offs, FILE_ON_KPROBE); + if (ctx->flags & TPARG_FL_KERNEL) { + trace_probe_log_err(ctx->offset, FILE_ON_KPROBE); return -EINVAL; } ret = kstrtol(arg + 2, 0, &offset); if (ret) { - trace_probe_log_err(offs, BAD_FILE_OFFS); + trace_probe_log_err(ctx->offset, BAD_FILE_OFFS); break; } @@ -433,8 +720,8 @@ parse_probe_arg(char *arg, const struct fetch_type *type, code->immediate = (unsigned long)offset; // imm64? } else { /* uprobes don't support symbols */ - if (!(flags & TPARG_FL_KERNEL)) { - trace_probe_log_err(offs, SYM_ON_UPROBE); + if (!(ctx->flags & TPARG_FL_KERNEL)) { + trace_probe_log_err(ctx->offset, SYM_ON_UPROBE); return -EINVAL; } /* Preserve symbol for updating */ @@ -443,7 +730,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, if (!code->data) return -ENOMEM; if (++code == end) { - trace_probe_log_err(offs, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); return -EINVAL; } code->op = FETCH_OP_IMM; @@ -451,7 +738,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, } /* These are fetching from memory */ if (++code == end) { - trace_probe_log_err(offs, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); return -EINVAL; } *pcode = code; @@ -470,36 +757,38 @@ parse_probe_arg(char *arg, const struct fetch_type *type, arg++; /* Skip '+', because kstrtol() rejects it. */ tmp = strchr(arg, '('); if (!tmp) { - trace_probe_log_err(offs, DEREF_NEED_BRACE); + trace_probe_log_err(ctx->offset, DEREF_NEED_BRACE); return -EINVAL; } *tmp = '\0'; ret = kstrtol(arg, 0, &offset); if (ret) { - trace_probe_log_err(offs, BAD_DEREF_OFFS); + trace_probe_log_err(ctx->offset, BAD_DEREF_OFFS); break; } - offs += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0); + ctx->offset += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0); arg = tmp + 1; tmp = strrchr(arg, ')'); if (!tmp) { - trace_probe_log_err(offs + strlen(arg), + trace_probe_log_err(ctx->offset + strlen(arg), DEREF_OPEN_BRACE); return -EINVAL; } else { - const struct fetch_type *t2 = find_fetch_type(NULL, flags); + const struct fetch_type *t2 = find_fetch_type(NULL, ctx->flags); + int cur_offs = ctx->offset; *tmp = '\0'; - ret = parse_probe_arg(arg, t2, &code, end, flags, offs); + ret = parse_probe_arg(arg, t2, &code, end, ctx); if (ret) break; + ctx->offset = cur_offs; if (code->op == FETCH_OP_COMM || code->op == FETCH_OP_DATA) { - trace_probe_log_err(offs, COMM_CANT_DEREF); + trace_probe_log_err(ctx->offset, COMM_CANT_DEREF); return -EINVAL; } if (++code == end) { - trace_probe_log_err(offs, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); return -EINVAL; } *pcode = code; @@ -510,7 +799,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, break; case '\\': /* Immediate value */ if (arg[1] == '"') { /* Immediate string */ - ret = __parse_imm_string(arg + 2, &tmp, offs + 2); + ret = __parse_imm_string(arg + 2, &tmp, ctx->offset + 2); if (ret) break; code->op = FETCH_OP_DATA; @@ -518,15 +807,24 @@ parse_probe_arg(char *arg, const struct fetch_type *type, } else { ret = str_to_immediate(arg + 1, &code->immediate); if (ret) - trace_probe_log_err(offs + 1, BAD_IMM); + trace_probe_log_err(ctx->offset + 1, BAD_IMM); else code->op = FETCH_OP_IMM; } break; + default: + if (isalpha(arg[0]) || arg[0] == '_') { /* BTF variable */ + if (!tparg_is_function_entry(ctx->flags)) { + trace_probe_log_err(ctx->offset, NOSUP_BTFARG); + return -EINVAL; + } + ret = parse_btf_arg(arg, code, ctx); + break; + } } if (!ret && code->op == FETCH_OP_NOP) { /* Parsed, but do not find fetch method */ - trace_probe_log_err(offs, BAD_FETCH_ARG); + trace_probe_log_err(ctx->offset, BAD_FETCH_ARG); ret = -EINVAL; } return ret; @@ -571,12 +869,13 @@ static int __parse_bitfield_probe_arg(const char *bf, /* String length checking wrapper */ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, - struct probe_arg *parg, unsigned int flags, int offset) + struct probe_arg *parg, + struct traceprobe_parse_context *ctx) { struct fetch_insn *code, *scode, *tmp = NULL; char *t, *t2, *t3; - char *arg; int ret, len; + char *arg; arg = kstrdup(argv, GFP_KERNEL); if (!arg) @@ -585,10 +884,10 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, ret = -EINVAL; len = strlen(arg); if (len > MAX_ARGSTR_LEN) { - trace_probe_log_err(offset, ARG_TOO_LONG); + trace_probe_log_err(ctx->offset, ARG_TOO_LONG); goto out; } else if (len == 0) { - trace_probe_log_err(offset, NO_ARG_BODY); + trace_probe_log_err(ctx->offset, NO_ARG_BODY); goto out; } @@ -606,23 +905,24 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, *t2++ = '\0'; t3 = strchr(t2, ']'); if (!t3) { - offset += t2 + strlen(t2) - arg; - trace_probe_log_err(offset, + int offs = t2 + strlen(t2) - arg; + + trace_probe_log_err(ctx->offset + offs, ARRAY_NO_CLOSE); goto out; } else if (t3[1] != '\0') { - trace_probe_log_err(offset + t3 + 1 - arg, + trace_probe_log_err(ctx->offset + t3 + 1 - arg, BAD_ARRAY_SUFFIX); goto out; } *t3 = '\0'; if (kstrtouint(t2, 0, &parg->count) || !parg->count) { - trace_probe_log_err(offset + t2 - arg, + trace_probe_log_err(ctx->offset + t2 - arg, BAD_ARRAY_NUM); goto out; } if (parg->count > MAX_ARRAY_LEN) { - trace_probe_log_err(offset + t2 - arg, + trace_probe_log_err(ctx->offset + t2 - arg, ARRAY_TOO_BIG); goto out; } @@ -633,17 +933,17 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, * Since $comm and immediate string can not be dereferenced, * we can find those by strcmp. But ignore for eprobes. */ - if (!(flags & TPARG_FL_TPOINT) && + if (!(ctx->flags & TPARG_FL_TEVENT) && (strcmp(arg, "$comm") == 0 || strcmp(arg, "$COMM") == 0 || strncmp(arg, "\\\"", 2) == 0)) { /* The type of $comm must be "string", and not an array. */ if (parg->count || (t && strcmp(t, "string"))) goto out; - parg->type = find_fetch_type("string", flags); + parg->type = find_fetch_type("string", ctx->flags); } else - parg->type = find_fetch_type(t, flags); + parg->type = find_fetch_type(t, ctx->flags); if (!parg->type) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_TYPE); + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_TYPE); goto out; } parg->offset = *size; @@ -665,10 +965,18 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, code[FETCH_INSN_MAX - 1].op = FETCH_OP_END; ret = parse_probe_arg(arg, parg->type, &code, &code[FETCH_INSN_MAX - 1], - flags, offset); + ctx); if (ret) goto fail; + /* Update storing type if BTF is available */ + if (IS_ENABLED(CONFIG_PROBE_EVENTS_BTF_ARGS) && !t) { + if (code->op == FETCH_OP_ARG) + parg->type = parse_btf_arg_type(code->param, ctx); + else if (code->op == FETCH_OP_RETVAL) + parg->type = parse_btf_retval_type(ctx); + } + ret = -EINVAL; /* Store operation */ if (parg->type->is_string) { @@ -676,7 +984,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (code->op != FETCH_OP_REG && code->op != FETCH_OP_STACK && code->op != FETCH_OP_RETVAL && code->op != FETCH_OP_ARG && code->op != FETCH_OP_DEREF && code->op != FETCH_OP_TP_ARG) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_SYMSTRING); goto fail; } @@ -684,7 +992,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF && code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM && code->op != FETCH_OP_DATA && code->op != FETCH_OP_TP_ARG) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_STRING); goto fail; } @@ -703,7 +1011,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, */ code++; if (code->op != FETCH_OP_NOP) { - trace_probe_log_err(offset, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); goto fail; } } @@ -726,7 +1034,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, } else { code++; if (code->op != FETCH_OP_NOP) { - trace_probe_log_err(offset, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); goto fail; } code->op = FETCH_OP_ST_RAW; @@ -737,7 +1045,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (t != NULL) { ret = __parse_bitfield_probe_arg(t, parg->type, &code); if (ret) { - trace_probe_log_err(offset + t - arg, BAD_BITFIELD); + trace_probe_log_err(ctx->offset + t - arg, BAD_BITFIELD); goto fail; } } @@ -747,13 +1055,13 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (scode->op != FETCH_OP_ST_MEM && scode->op != FETCH_OP_ST_STRING && scode->op != FETCH_OP_ST_USTRING) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_STRING); goto fail; } code++; if (code->op != FETCH_OP_NOP) { - trace_probe_log_err(offset, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); goto fail; } code->op = FETCH_OP_LP_ARRAY; @@ -801,8 +1109,35 @@ static int traceprobe_conflict_field_name(const char *name, return 0; } +static char *generate_probe_arg_name(const char *arg, int idx) +{ + char *name = NULL; + const char *end; + + /* + * If argument name is omitted, try arg as a name (BTF variable) + * or "argN". + */ + if (IS_ENABLED(CONFIG_PROBE_EVENTS_BTF_ARGS)) { + end = strchr(arg, ':'); + if (!end) + end = arg + strlen(arg); + + name = kmemdup_nul(arg, end - arg, GFP_KERNEL); + if (!name || !is_good_name(name)) { + kfree(name); + name = NULL; + } + } + + if (!name) + name = kasprintf(GFP_KERNEL, "arg%d", idx + 1); + + return name; +} + int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg, - unsigned int flags) + struct traceprobe_parse_context *ctx) { struct probe_arg *parg = &tp->args[i]; const char *body; @@ -822,8 +1157,7 @@ int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg, parg->name = kmemdup_nul(arg, body - arg, GFP_KERNEL); body++; } else { - /* If argument name is omitted, set "argN" */ - parg->name = kasprintf(GFP_KERNEL, "arg%d", i + 1); + parg->name = generate_probe_arg_name(arg, i); body = arg; } if (!parg->name) @@ -837,9 +1171,9 @@ int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg, trace_probe_log_err(0, USED_ARG_NAME); return -EINVAL; } + ctx->offset = body - arg; /* Parse fetch argument */ - return traceprobe_parse_probe_arg_body(body, &tp->size, parg, flags, - body - arg); + return traceprobe_parse_probe_arg_body(body, &tp->size, parg, ctx); } void traceprobe_free_probe_arg(struct probe_arg *arg) @@ -858,6 +1192,151 @@ void traceprobe_free_probe_arg(struct probe_arg *arg) kfree(arg->fmt); } +static int argv_has_var_arg(int argc, const char *argv[], int *args_idx, + struct traceprobe_parse_context *ctx) +{ + int i, found = 0; + + for (i = 0; i < argc; i++) + if (str_has_prefix(argv[i], "$arg")) { + trace_probe_log_set_index(i + 2); + + if (!tparg_is_function_entry(ctx->flags)) { + trace_probe_log_err(0, NOFENTRY_ARGS); + return -EINVAL; + } + + if (isdigit(argv[i][4])) { + found = 1; + continue; + } + + if (argv[i][4] != '*') { + trace_probe_log_err(0, BAD_VAR); + return -EINVAL; + } + + if (*args_idx >= 0 && *args_idx < argc) { + trace_probe_log_err(0, DOUBLE_ARGS); + return -EINVAL; + } + found = 1; + *args_idx = i; + } + + return found; +} + +static int sprint_nth_btf_arg(int idx, const char *type, + char *buf, int bufsize, + struct traceprobe_parse_context *ctx) +{ + struct btf *btf = traceprobe_get_btf(); + const char *name; + int ret; + + if (idx >= ctx->nr_params) { + trace_probe_log_err(0, NO_BTFARG); + return -ENOENT; + } + name = btf_name_by_offset(btf, ctx->params[idx].name_off); + if (!name) { + trace_probe_log_err(0, NO_BTF_ENTRY); + return -ENOENT; + } + ret = snprintf(buf, bufsize, "%s%s", name, type); + if (ret >= bufsize) { + trace_probe_log_err(0, ARGS_2LONG); + return -E2BIG; + } + return ret; +} + +/* Return new_argv which must be freed after use */ +const char **traceprobe_expand_meta_args(int argc, const char *argv[], + int *new_argc, char *buf, int bufsize, + struct traceprobe_parse_context *ctx) +{ + const struct btf_param *params = NULL; + int i, j, n, used, ret, args_idx = -1; + const char **new_argv = NULL; + int nr_params; + + ret = argv_has_var_arg(argc, argv, &args_idx, ctx); + if (ret < 0) + return ERR_PTR(ret); + + if (!ret) { + *new_argc = argc; + return NULL; + } + + params = find_btf_func_param(ctx->funcname, &nr_params, + ctx->flags & TPARG_FL_TPOINT); + if (IS_ERR(params)) { + if (args_idx != -1) { + /* $arg* requires BTF info */ + trace_probe_log_err(0, NOSUP_BTFARG); + return (const char **)params; + } + *new_argc = argc; + return NULL; + } + ctx->params = params; + ctx->nr_params = nr_params; + + if (args_idx >= 0) + *new_argc = argc + ctx->nr_params - 1; + else + *new_argc = argc; + + new_argv = kcalloc(*new_argc, sizeof(char *), GFP_KERNEL); + if (!new_argv) + return ERR_PTR(-ENOMEM); + + used = 0; + for (i = 0, j = 0; i < argc; i++) { + trace_probe_log_set_index(i + 2); + if (i == args_idx) { + for (n = 0; n < nr_params; n++) { + ret = sprint_nth_btf_arg(n, "", buf + used, + bufsize - used, ctx); + if (ret < 0) + goto error; + + new_argv[j++] = buf + used; + used += ret + 1; + } + continue; + } + + if (str_has_prefix(argv[i], "$arg")) { + char *type = NULL; + + n = simple_strtoul(argv[i] + 4, &type, 10); + if (type && !(*type == ':' || *type == '\0')) { + trace_probe_log_err(0, BAD_VAR); + ret = -ENOENT; + goto error; + } + /* Note: $argN starts from $arg1 */ + ret = sprint_nth_btf_arg(n - 1, type, buf + used, + bufsize - used, ctx); + if (ret < 0) + goto error; + new_argv[j++] = buf + used; + used += ret + 1; + } else + new_argv[j++] = argv[i]; + } + + return new_argv; + +error: + kfree(new_argv); + return ERR_PTR(ret); +} + int traceprobe_update_arg(struct probe_arg *arg) { struct fetch_insn *code = arg->code; diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 6a4ecfb1da43..01ea148723de 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -23,6 +23,7 @@ #include #include #include +#include #include #include "trace.h" @@ -32,7 +33,9 @@ #define MAX_ARGSTR_LEN 63 #define MAX_ARRAY_LEN 64 #define MAX_ARG_NAME_LEN 32 +#define MAX_BTF_ARGS_LEN 128 #define MAX_STRING_SIZE PATH_MAX +#define MAX_ARG_BUF_LEN (MAX_TRACE_ARGS * MAX_ARG_NAME_LEN) /* Reserved field names */ #define FIELD_STRING_IP "__probe_ip" @@ -357,15 +360,42 @@ int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_a #define trace_probe_for_each_link_rcu(pos, tp) \ list_for_each_entry_rcu(pos, &(tp)->event->files, list) +/* + * The flags used for parsing trace_probe arguments. + * TPARG_FL_RETURN, TPARG_FL_FENTRY and TPARG_FL_TEVENT are mutually exclusive. + * TPARG_FL_KERNEL and TPARG_FL_USER are also mutually exclusive. + * TPARG_FL_FPROBE and TPARG_FL_TPOINT are optional but it should be with + * TPARG_FL_KERNEL. + */ #define TPARG_FL_RETURN BIT(0) #define TPARG_FL_KERNEL BIT(1) #define TPARG_FL_FENTRY BIT(2) -#define TPARG_FL_TPOINT BIT(3) +#define TPARG_FL_TEVENT BIT(3) #define TPARG_FL_USER BIT(4) -#define TPARG_FL_MASK GENMASK(4, 0) +#define TPARG_FL_FPROBE BIT(5) +#define TPARG_FL_TPOINT BIT(6) +#define TPARG_FL_LOC_MASK GENMASK(4, 0) + +static inline bool tparg_is_function_entry(unsigned int flags) +{ + return (flags & TPARG_FL_LOC_MASK) == (TPARG_FL_KERNEL | TPARG_FL_FENTRY); +} + +struct traceprobe_parse_context { + struct trace_event_call *event; + const struct btf_param *params; + s32 nr_params; + const char *funcname; + unsigned int flags; + int offset; +}; extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, - const char *argv, unsigned int flags); + const char *argv, + struct traceprobe_parse_context *ctx); +const char **traceprobe_expand_meta_args(int argc, const char *argv[], + int *new_argc, char *buf, int bufsize, + struct traceprobe_parse_context *ctx); extern int traceprobe_update_arg(struct probe_arg *arg); extern void traceprobe_free_probe_arg(struct probe_arg *arg); @@ -404,11 +434,12 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(REFCNT_OPEN_BRACE, "Reference counter brace is not closed"), \ C(BAD_REFCNT_SUFFIX, "Reference counter has wrong suffix"), \ C(BAD_UPROBE_OFFS, "Invalid uprobe offset"), \ - C(MAXACT_NO_KPROBE, "Maxactive is not for kprobe"), \ + C(BAD_MAXACT_TYPE, "Maxactive is only for function exit"), \ C(BAD_MAXACT, "Invalid maxactive number"), \ C(MAXACT_TOO_BIG, "Maxactive is too big"), \ C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \ C(BAD_RETPROBE, "Retprobe address must be an function entry"), \ + C(NO_TRACEPOINT, "Tracepoint is not found"), \ C(BAD_ADDR_SUFFIX, "Invalid probed address suffix"), \ C(NO_GROUP_NAME, "Group name is not specified"), \ C(GROUP_TOO_LONG, "Group name is too long"), \ @@ -418,6 +449,7 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(BAD_EVENT_NAME, "Event name must follow the same rules as C identifiers"), \ C(EVENT_EXIST, "Given group/event name is already used by another event"), \ C(RETVAL_ON_PROBE, "$retval is not available on probe"), \ + C(NO_RETVAL, "This function returns 'void' type"), \ C(BAD_STACK_NUM, "Invalid stack number"), \ C(BAD_ARG_NUM, "Invalid argument number"), \ C(BAD_VAR, "Invalid $-valiable specified"), \ @@ -456,7 +488,14 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(NO_EVENT_INFO, "This requires both group and event name to attach"),\ C(BAD_ATTACH_EVENT, "Attached event does not exist"),\ C(BAD_ATTACH_ARG, "Attached event does not have this field"),\ - C(NO_EP_FILTER, "No filter rule after 'if'"), + C(NO_EP_FILTER, "No filter rule after 'if'"), \ + C(NOSUP_BTFARG, "BTF is not available or not supported"), \ + C(NO_BTFARG, "This variable is not found at this probe point"),\ + C(NO_BTF_ENTRY, "No BTF entry for this probe point"), \ + C(BAD_VAR_ARGS, "$arg* must be an independent parameter without name etc."),\ + C(NOFENTRY_ARGS, "$arg* can be used only on function entry"), \ + C(DOUBLE_ARGS, "$arg* can be used only once in the parameters"), \ + C(ARGS_2LONG, "$arg* failed because the argument list is too long"), #undef C #define C(a, b) TP_ERR_##a diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 8b92e34ff0c8..fa09b33ee731 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -686,10 +686,12 @@ static int __trace_uprobe_create(int argc, const char **argv) /* parse arguments */ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct traceprobe_parse_context ctx = { + .flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER, + }; + trace_probe_log_set_index(i + 2); - ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], - (is_return ? TPARG_FL_RETURN : 0) | - TPARG_FL_USER); + ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], &ctx); if (ret) goto error; } diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c index 079435a2e26c..24de0e5ff859 100644 --- a/lib/test_fprobe.c +++ b/lib/test_fprobe.c @@ -39,7 +39,8 @@ static noinline u32 fprobe_selftest_nest_target(u32 value, u32 (*nest)(u32)) } static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip, - struct pt_regs *regs, void *data) + unsigned long ret_ip, + struct pt_regs *regs, void *data) { KUNIT_EXPECT_FALSE(current_test, preemptible()); /* This can be called on the fprobe_selftest_target and the fprobe_selftest_target2 */ @@ -57,6 +58,7 @@ static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip, } static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip, + unsigned long ret_ip, struct pt_regs *regs, void *data) { unsigned long ret = regs_return_value(regs); @@ -78,14 +80,16 @@ static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip, } static notrace int nest_entry_handler(struct fprobe *fp, unsigned long ip, - struct pt_regs *regs, void *data) + unsigned long ret_ip, + struct pt_regs *regs, void *data) { KUNIT_EXPECT_FALSE(current_test, preemptible()); return 0; } static notrace void nest_exit_handler(struct fprobe *fp, unsigned long ip, - struct pt_regs *regs, void *data) + unsigned long ret_ip, + struct pt_regs *regs, void *data) { KUNIT_EXPECT_FALSE(current_test, preemptible()); KUNIT_EXPECT_EQ(current_test, ip, target_nest_ip); diff --git a/samples/fprobe/fprobe_example.c b/samples/fprobe/fprobe_example.c index 4efc8feb6277..64e715e7ed11 100644 --- a/samples/fprobe/fprobe_example.c +++ b/samples/fprobe/fprobe_example.c @@ -49,6 +49,7 @@ static void show_backtrace(void) } static int sample_entry_handler(struct fprobe *fp, unsigned long ip, + unsigned long ret_ip, struct pt_regs *regs, void *data) { if (use_trace) @@ -65,10 +66,11 @@ static int sample_entry_handler(struct fprobe *fp, unsigned long ip, return 0; } -static void sample_exit_handler(struct fprobe *fp, unsigned long ip, struct pt_regs *regs, +static void sample_exit_handler(struct fprobe *fp, unsigned long ip, + unsigned long ret_ip, struct pt_regs *regs, void *data) { - unsigned long rip = instruction_pointer(regs); + unsigned long rip = ret_ip; if (use_trace) /* diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_btfarg.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_btfarg.tc new file mode 100644 index 000000000000..b89de1771655 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_btfarg.tc @@ -0,0 +1,58 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Generic dynamic event - add/remove probes with BTF arguments +# requires: dynamic_events "":README + +KPROBES= +FPROBES= + +if grep -qF "p[:[/][]] []" README ; then + KPROBES=yes +fi +if grep -qF "f[:[/][]] [%return] []" README ; then + FPROBES=yes +fi + +if [ -z "$KPROBES" -a "$FPROBES" ] ; then + exit_unsupported +fi + +echo 0 > events/enable +echo > dynamic_events + +TP=kfree + +if [ "$FPROBES" ] ; then +echo "f:fpevent $TP object" >> dynamic_events +echo "t:tpevent $TP ptr" >> dynamic_events + +grep -q "fpevent.*object=object" dynamic_events +grep -q "tpevent.*ptr=ptr" dynamic_events + +echo > dynamic_events + +echo "f:fpevent $TP "'$arg1' >> dynamic_events +grep -q "fpevent.*object=object" dynamic_events +echo > dynamic_events + +echo "f:fpevent $TP "'$arg*' >> dynamic_events +echo "t:tpevent $TP "'$arg*' >> dynamic_events + +grep -q "fpevent.*object=object" dynamic_events +grep -q "tpevent.*ptr=ptr" dynamic_events +! grep -q "tpevent.*_data" dynamic_events +fi + +echo > dynamic_events + +if [ "$KPROBES" ] ; then +echo "p:kpevent $TP object" >> dynamic_events +grep -q "kpevent.*object=object" dynamic_events + +echo > dynamic_events + +echo "p:kpevent $TP "'$arg*' >> dynamic_events +grep -q "kpevent.*object=object" dynamic_events +fi + +clear_trace diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe.tc new file mode 100644 index 000000000000..dc25bcf4f9e2 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe.tc @@ -0,0 +1,26 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Generic dynamic event - add/remove fprobe events +# requires: dynamic_events "f[:[/][]] [%return] []":README + +echo 0 > events/enable +echo > dynamic_events + +PLACE=$FUNCTION_FORK + +echo "f:myevent1 $PLACE" >> dynamic_events +echo "f:myevent2 $PLACE%return" >> dynamic_events + +grep -q myevent1 dynamic_events +grep -q myevent2 dynamic_events +test -d events/fprobes/myevent1 +test -d events/fprobes/myevent2 + +echo "-:myevent2" >> dynamic_events + +grep -q myevent1 dynamic_events +! grep -q myevent2 dynamic_events + +echo > dynamic_events + +clear_trace diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc new file mode 100644 index 000000000000..155792eaeee5 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_tprobe.tc @@ -0,0 +1,27 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Generic dynamic event - add/remove tracepoint probe events +# requires: dynamic_events "t[:[/][]] []":README + +echo 0 > events/enable +echo > dynamic_events + +TRACEPOINT1=kmem_cache_alloc +TRACEPOINT2=kmem_cache_free + +echo "t:myevent1 $TRACEPOINT1" >> dynamic_events +echo "t:myevent2 $TRACEPOINT2" >> dynamic_events + +grep -q myevent1 dynamic_events +grep -q myevent2 dynamic_events +test -d events/tracepoints/myevent1 +test -d events/tracepoints/myevent2 + +echo "-:myevent2" >> dynamic_events + +grep -q myevent1 dynamic_events +! grep -q myevent2 dynamic_events + +echo > dynamic_events + +clear_trace diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc new file mode 100644 index 000000000000..812f5b3f6055 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc @@ -0,0 +1,111 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Fprobe event parser error log check +# requires: dynamic_events "f[:[/][]] [%return] []":README + +check_error() { # command-with-error-pos-by-^ + ftrace_errlog_check 'trace_fprobe' "$1" 'dynamic_events' +} + +case `uname -m` in +x86_64|i[3456]86) + REG=%ax ;; +aarch64) + REG=%x0 ;; +*) + REG=%r0 ;; +esac + +check_error 'f^100 vfs_read' # MAXACT_NO_KPROBE +check_error 'f^1a111 vfs_read' # BAD_MAXACT +check_error 'f^100000 vfs_read' # MAXACT_TOO_BIG + +check_error 'f ^non_exist_func' # BAD_PROBE_ADDR (enoent) +check_error 'f ^vfs_read+10' # BAD_PROBE_ADDR +check_error 'f:^/bar vfs_read' # NO_GROUP_NAME +check_error 'f:^12345678901234567890123456789012345678901234567890123456789012345/bar vfs_read' # GROUP_TOO_LONG + +check_error 'f:^foo.1/bar vfs_read' # BAD_GROUP_NAME +check_error 'f:^ vfs_read' # NO_EVENT_NAME +check_error 'f:foo/^12345678901234567890123456789012345678901234567890123456789012345 vfs_read' # EVENT_TOO_LONG +check_error 'f:foo/^bar.1 vfs_read' # BAD_EVENT_NAME + +check_error 'f vfs_read ^$retval' # RETVAL_ON_PROBE +check_error 'f vfs_read ^$stack10000' # BAD_STACK_NUM + +check_error 'f vfs_read ^$arg10000' # BAD_ARG_NUM + +check_error 'f vfs_read ^$none_var' # BAD_VAR +check_error 'f vfs_read ^'$REG # BAD_VAR + +check_error 'f vfs_read ^@12345678abcde' # BAD_MEM_ADDR +check_error 'f vfs_read ^@+10' # FILE_ON_KPROBE + +grep -q "imm-value" README && \ +check_error 'f vfs_read arg1=\^x' # BAD_IMM +grep -q "imm-string" README && \ +check_error 'f vfs_read arg1=\"abcd^' # IMMSTR_NO_CLOSE + +check_error 'f vfs_read ^+0@0)' # DEREF_NEED_BRACE +check_error 'f vfs_read ^+0ab1(@0)' # BAD_DEREF_OFFS +check_error 'f vfs_read +0(+0(@0^)' # DEREF_OPEN_BRACE + +if grep -A1 "fetcharg:" README | grep -q '\$comm' ; then +check_error 'f vfs_read +0(^$comm)' # COMM_CANT_DEREF +fi + +check_error 'f vfs_read ^&1' # BAD_FETCH_ARG + + +# We've introduced this limitation with array support +if grep -q ' \\\[\\\]' README; then +check_error 'f vfs_read +0(^+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(@0))))))))))))))' # TOO_MANY_OPS? +check_error 'f vfs_read +0(@11):u8[10^' # ARRAY_NO_CLOSE +check_error 'f vfs_read +0(@11):u8[10]^a' # BAD_ARRAY_SUFFIX +check_error 'f vfs_read +0(@11):u8[^10a]' # BAD_ARRAY_NUM +check_error 'f vfs_read +0(@11):u8[^256]' # ARRAY_TOO_BIG +fi + +check_error 'f vfs_read @11:^unknown_type' # BAD_TYPE +check_error 'f vfs_read $stack0:^string' # BAD_STRING +check_error 'f vfs_read @11:^b10@a/16' # BAD_BITFIELD + +check_error 'f vfs_read ^arg123456789012345678901234567890=@11' # ARG_NAME_TOO_LOG +check_error 'f vfs_read ^=@11' # NO_ARG_NAME +check_error 'f vfs_read ^var.1=@11' # BAD_ARG_NAME +check_error 'f vfs_read var1=@11 ^var1=@12' # USED_ARG_NAME +check_error 'f vfs_read ^+1234567(+1234567(+1234567(+1234567(+1234567(+1234567(@1234))))))' # ARG_TOO_LONG +check_error 'f vfs_read arg1=^' # NO_ARG_BODY + + +# multiprobe errors +if grep -q "Create/append/" README && grep -q "imm-value" README; then +echo "f:fprobes/testevent $FUNCTION_FORK" > dynamic_events +check_error '^f:fprobes/testevent do_exit%return' # DIFF_PROBE_TYPE + +# Explicitly use printf "%s" to not interpret \1 +printf "%s" "f:fprobes/testevent $FUNCTION_FORK abcd=\\1" > dynamic_events +check_error "f:fprobes/testevent $FUNCTION_FORK ^bcd=\\1" # DIFF_ARG_TYPE +check_error "f:fprobes/testevent $FUNCTION_FORK ^abcd=\\1:u8" # DIFF_ARG_TYPE +check_error "f:fprobes/testevent $FUNCTION_FORK ^abcd=\\\"foo\"" # DIFF_ARG_TYPE +check_error "^f:fprobes/testevent $FUNCTION_FORK abcd=\\1" # SAME_PROBE +fi + +# %return suffix errors +check_error 'f vfs_read^%hoge' # BAD_ADDR_SUFFIX + +# BTF arguments errors +if grep -q "" README; then +check_error 'f vfs_read args=^$arg*' # BAD_VAR_ARGS +check_error 'f vfs_read +0(^$arg*)' # BAD_VAR_ARGS +check_error 'f vfs_read $arg* ^$arg*' # DOUBLE_ARGS +check_error 'f vfs_read%return ^$arg*' # NOFENTRY_ARGS +check_error 'f vfs_read ^hoge' # NO_BTFARG +check_error 'f kfree ^$arg10' # NO_BTFARG (exceed the number of parameters) +check_error 'f kfree%return ^$retval' # NO_RETVAL +else +check_error 'f vfs_read ^$arg*' # NOSUP_BTFARG +check_error 't kfree ^$arg*' # NOSUP_BTFARG +fi + +exit 0 diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/tprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/tprobe_syntax_errors.tc new file mode 100644 index 000000000000..da117b8f1d12 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/dynevent/tprobe_syntax_errors.tc @@ -0,0 +1,82 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Tracepoint probe event parser error log check +# requires: dynamic_events "t[:[/][]] []":README + +check_error() { # command-with-error-pos-by-^ + ftrace_errlog_check 'trace_fprobe' "$1" 'dynamic_events' +} + +check_error 't^100 kfree' # BAD_MAXACT_TYPE + +check_error 't ^non_exist_tracepoint' # NO_TRACEPOINT +check_error 't:^/bar kfree' # NO_GROUP_NAME +check_error 't:^12345678901234567890123456789012345678901234567890123456789012345/bar kfree' # GROUP_TOO_LONG + +check_error 't:^foo.1/bar kfree' # BAD_GROUP_NAME +check_error 't:^ kfree' # NO_EVENT_NAME +check_error 't:foo/^12345678901234567890123456789012345678901234567890123456789012345 kfree' # EVENT_TOO_LONG +check_error 't:foo/^bar.1 kfree' # BAD_EVENT_NAME + +check_error 't kfree ^$retval' # RETVAL_ON_PROBE +check_error 't kfree ^$stack10000' # BAD_STACK_NUM + +check_error 't kfree ^$arg10000' # BAD_ARG_NUM + +check_error 't kfree ^$none_var' # BAD_VAR +check_error 't kfree ^%rax' # BAD_VAR + +check_error 't kfree ^@12345678abcde' # BAD_MEM_ADDR +check_error 't kfree ^@+10' # FILE_ON_KPROBE + +grep -q "imm-value" README && \ +check_error 't kfree arg1=\^x' # BAD_IMM +grep -q "imm-string" README && \ +check_error 't kfree arg1=\"abcd^' # IMMSTR_NO_CLOSE + +check_error 't kfree ^+0@0)' # DEREF_NEED_BRACE +check_error 't kfree ^+0ab1(@0)' # BAD_DEREF_OFFS +check_error 't kfree +0(+0(@0^)' # DEREF_OPEN_BRACE + +if grep -A1 "fetcharg:" README | grep -q '\$comm' ; then +check_error 't kfree +0(^$comm)' # COMM_CANT_DEREF +fi + +check_error 't kfree ^&1' # BAD_FETCH_ARG + + +# We've introduced this limitation with array support +if grep -q ' \\\[\\\]' README; then +check_error 't kfree +0(^+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(+0(@0))))))))))))))' # TOO_MANY_OPS? +check_error 't kfree +0(@11):u8[10^' # ARRAY_NO_CLOSE +check_error 't kfree +0(@11):u8[10]^a' # BAD_ARRAY_SUFFIX +check_error 't kfree +0(@11):u8[^10a]' # BAD_ARRAY_NUM +check_error 't kfree +0(@11):u8[^256]' # ARRAY_TOO_BIG +fi + +check_error 't kfree @11:^unknown_type' # BAD_TYPE +check_error 't kfree $stack0:^string' # BAD_STRING +check_error 't kfree @11:^b10@a/16' # BAD_BITFIELD + +check_error 't kfree ^arg123456789012345678901234567890=@11' # ARG_NAME_TOO_LOG +check_error 't kfree ^=@11' # NO_ARG_NAME +check_error 't kfree ^var.1=@11' # BAD_ARG_NAME +check_error 't kfree var1=@11 ^var1=@12' # USED_ARG_NAME +check_error 't kfree ^+1234567(+1234567(+1234567(+1234567(+1234567(+1234567(@1234))))))' # ARG_TOO_LONG +check_error 't kfree arg1=^' # NO_ARG_BODY + + +# multiprobe errors +if grep -q "Create/append/" README && grep -q "imm-value" README; then +echo "t:tracepoint/testevent kfree" > dynamic_events +check_error '^f:tracepoint/testevent kfree' # DIFF_PROBE_TYPE + +# Explicitly use printf "%s" to not interpret \1 +printf "%s" "t:tracepoints/testevent kfree abcd=\\1" > dynamic_events +check_error "t:tracepoints/testevent kfree ^bcd=\\1" # DIFF_ARG_TYPE +check_error "t:tracepoints/testevent kfree ^abcd=\\1:u8" # DIFF_ARG_TYPE +check_error "t:tracepoints/testevent kfree ^abcd=\\\"foo\"" # DIFF_ARG_TYPE +check_error "^t:tracepoints/testevent kfree abcd=\\1" # SAME_PROBE +fi + +exit 0 diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_insn_boundary.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_insn_boundary.tc new file mode 100644 index 000000000000..4f7cc318f331 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_insn_boundary.tc @@ -0,0 +1,19 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0-or-later +# Copyright (C) 2023 Akanksha J N, IBM corporation +# description: Register multiple kprobe events in a function +# requires: kprobe_events + +for i in `seq 0 255`; do + echo p $FUNCTION_FORK+${i} >> kprobe_events || continue +done + +cat kprobe_events >> $testlog + +echo 1 > events/kprobes/enable +( echo "forked" ) +echo 0 > events/kprobes/enable +echo > kprobe_events +echo "Waiting for unoptimizing & freeing" +sleep 5 +echo "Done" diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc index 9e85d3019ff0..65fbb26fd58c 100644 --- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc @@ -8,7 +8,7 @@ check_error() { # command-with-error-pos-by-^ } if grep -q 'r\[maxactive\]' README; then -check_error 'p^100 vfs_read' # MAXACT_NO_KPROBE +check_error 'p^100 vfs_read' # BAD_MAXACT_TYPE check_error 'r^1a111 vfs_read' # BAD_MAXACT check_error 'r^100000 vfs_read' # MAXACT_TOO_BIG fi @@ -103,4 +103,18 @@ check_error 'p vfs_read^%hoge' # BAD_ADDR_SUFFIX check_error 'p ^vfs_read+10%return' # BAD_RETPROBE fi +# BTF arguments errors +if grep -q "" README; then +check_error 'p vfs_read args=^$arg*' # BAD_VAR_ARGS +check_error 'p vfs_read +0(^$arg*)' # BAD_VAR_ARGS +check_error 'p vfs_read $arg* ^$arg*' # DOUBLE_ARGS +check_error 'r vfs_read ^$arg*' # NOFENTRY_ARGS +check_error 'p vfs_read+8 ^$arg*' # NOFENTRY_ARGS +check_error 'p vfs_read ^hoge' # NO_BTFARG +check_error 'p kfree ^$arg10' # NO_BTFARG (exceed the number of parameters) +check_error 'r kfree ^$retval' # NO_RETVAL +else +check_error 'p vfs_read ^$arg*' # NOSUP_BTFARG +fi + exit 0