Commit Graph

1216122 Commits

Author SHA1 Message Date
Dave Marchevsky
f10ca5da5b bpf: Don't explicitly emit BTF for struct btf_iter_num
Commit 6018e1f407 ("bpf: implement numbers iterator") added the
BTF_TYPE_EMIT line that this patch is modifying. The struct btf_iter_num
doesn't exist, so only a forward declaration is emitted in BTF:

  FWD 'btf_iter_num' fwd_kind=struct

That commit was probably hoping to ensure that struct bpf_iter_num is
emitted in vmlinux BTF. A previous version of this patch changed the
line to emit the correct type, but Yonghong confirmed that it would
definitely be emitted regardless in [0], so this patch simply removes
the line.

This isn't marked "Fixes" because the extraneous btf_iter_num FWD wasn't
causing any issues that I noticed, aside from mild confusion when I
looked through the code.

  [0]: https://lore.kernel.org/bpf/25d08207-43e6-36a8-5e0f-47a913d4cda5@linux.dev/

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20231013204426.1074286-2-davemarchevsky@fb.com
2023-10-13 15:48:58 -07:00
Artem Savkov
ba8ea72388 bpf: Change syscall_nr type to int in struct syscall_tp_t
linux-rt-devel tree contains a patch (b1773eac3f29c ("sched: Add support
for lazy preemption")) that adds an extra member to struct trace_entry.
This causes the offset of args field in struct trace_event_raw_sys_enter
be different from the one in struct syscall_trace_enter:

struct trace_event_raw_sys_enter {
        struct trace_entry         ent;                  /*     0    12 */

        /* XXX last struct has 3 bytes of padding */
        /* XXX 4 bytes hole, try to pack */

        long int                   id;                   /*    16     8 */
        long unsigned int          args[6];              /*    24    48 */
        /* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */
        char                       __data[];             /*    72     0 */

        /* size: 72, cachelines: 2, members: 4 */
        /* sum members: 68, holes: 1, sum holes: 4 */
        /* paddings: 1, sum paddings: 3 */
        /* last cacheline: 8 bytes */
};

struct syscall_trace_enter {
        struct trace_entry         ent;                  /*     0    12 */

        /* XXX last struct has 3 bytes of padding */

        int                        nr;                   /*    12     4 */
        long unsigned int          args[];               /*    16     0 */

        /* size: 16, cachelines: 1, members: 3 */
        /* paddings: 1, sum paddings: 3 */
        /* last cacheline: 16 bytes */
};

This, in turn, causes perf_event_set_bpf_prog() fail while running bpf
test_profiler testcase because max_ctx_offset is calculated based on the
former struct, while off on the latter:

  10488         if (is_tracepoint || is_syscall_tp) {
  10489                 int off = trace_event_get_offsets(event->tp_event);
  10490
  10491                 if (prog->aux->max_ctx_offset > off)
  10492                         return -EACCES;
  10493         }

What bpf program is actually getting is a pointer to struct
syscall_tp_t, defined in kernel/trace/trace_syscalls.c. This patch fixes
the problem by aligning struct syscall_tp_t with struct
syscall_trace_(enter|exit) and changing the tests to use these structs
to dereference context.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/bpf/20231013054219.172920-1-asavkov@redhat.com
2023-10-13 12:39:36 -07:00
Martin KaFai Lau
9c1292eca2 net/bpf: Avoid unused "sin_addr_len" warning when CONFIG_CGROUP_BPF is not set
It was reported that there is a compiler warning on the unused variable
"sin_addr_len" in af_inet.c when CONFIG_CGROUP_BPF is not set.
This patch is to address it similar to the ipv6 counterpart
in inet6_getname(). It is to "return sin_addr_len;"
instead of "return sizeof(*sin);".

Fixes: fefba7d1ae ("bpf: Propagate modified uaddrlen from cgroup sockaddr programs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/bpf/20231013185702.3993710-1-martin.lau@linux.dev

Closes: https://lore.kernel.org/bpf/20231013114007.2fb09691@canb.auug.org.au/
2023-10-13 12:35:43 -07:00
Yafang Shao
236334aeec bpf: Avoid unnecessary audit log for CPU security mitigations
Check cpu_mitigations_off() first to avoid calling capable() if it is off.
This can avoid unnecessary audit log.

Fixes: bc5bc309db ("bpf: Inherit system settings for CPU security mitigations")
Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/CAEf4Bza6UVUWqcWQ-66weZ-nMDr+TFU3Mtq=dumZFD-pSqU7Ow@mail.gmail.com/
Link: https://lore.kernel.org/bpf/20231013083916.4199-1-laoar.shao@gmail.com
2023-10-13 12:33:21 -07:00
Martin KaFai Lau
d2dc885b8c Merge branch 'Add cgroup sockaddr hooks for unix sockets'
Daan De Meyer says:

====================
Changes since v10:

* Removed extra check from bpf_sock_addr_set_sun_path() again in favor of
  calling unix_validate_addr() everywhere in af_unix.c before calling the hooks.

Changes since v9:

* Renamed bpf_sock_addr_set_unix_addr() to bpf_sock_addr_set_sun_path() and
  rennamed arguments to match the new name.
* Added an extra check to bpf_sock_addr_set_sun_path() to disallow changing the
  address of an unnamed unix socket.
* Removed unnecessary NULL check on uaddrlen in
  __cgroup_bpf_run_filter_sock_addr().

Changes since v8:

* Added missing test programs to last patch

Changes since v7:

* Fixed formatting nit in comment
* Renamed from cgroup/connectun to cgroup/connect_unix (and similar for all
  other hooks)

Changes since v6:

* Actually removed bpf_bind() helper for AF_UNIX hooks.
* Fixed merge conflict
* Updated comment to mention uaddrlen is read-only for AF_INET[6]
* Removed unnecessary forward declaration of struct sock_addr_test
* Removed unused BPF_CGROUP_RUN_PROG_UNIX_CONNECT()
* Fixed formatting nit reported by checkpatch
* Added more information to commit message about recvmsg() on connected socket

Changes since v5:

* Fixed kernel version in bpftool documentation (6.3 => 6.7).
* Added connection mode socket recvmsg() test.
* Removed bpf_bind() helper for AF_UNIX hooks.
* Added missing getpeernameun and getsocknameun BPF test programs.
* Added note for bind() test being unused currently.

Changes since v4:

* Dropped support for intercepting bind() as when using bind() with unix sockets
  and a pathname sockaddr, bind() will create an inode in the filesystem that
  needs to be cleaned up. If the address is rewritten, users might try to clean
  up the wrong file and leak the actual socket file in the filesystem.
* Changed bpf_sock_addr_set_unix_addr() to use BTF_KFUNC_HOOK_CGROUP_SKB instead
  of BTF_KFUNC_HOOK_COMMON.
* Removed unix socket related changes from BPF_CGROUP_PRE_CONNECT_ENABLED() as
  unix sockets do not support pre-connect.
* Added tests for getpeernameun and getsocknameun hooks.
* We now disallow an empty sockaddr in bpf_sock_addr_set_unix_addr() similar to
  unix_validate_addr().
* Removed unnecessary cgroup_bpf_enabled() checks
* Removed unnecessary error checks

Changes since v3:

* Renamed bpf_sock_addr_set_addr() to bpf_sock_addr_set_unix_addr() and
  made it only operate on AF_UNIX sockaddrs. This is because for the other
  families, users usually want to configure more than just the address so
  a generic interface will not fit the bill here. e.g. for AF_INET and AF_INET6,
  users would generally also want to be able to configure the port which the
  current interface doesn't support. So we expose an AF_UNIX specific function
  instead.
* Made the tests in the new sock addr tests more generic (similar to test_sock_addr.c),
  this should make it easier to migrate the other sock addr tests in the future.
* Removed the new kfunc hook and attached to BTF_KFUNC_HOOK_COMMON instead
* Set uaddrlen to 0 when the family is AF_UNSPEC
* Pass in the addrlen to the hook from IPv6 code
* Fixed mount directory mkdir() to ignore EEXIST

Changes since v2:

* Configuring the sock addr is now done via a new kfunc bpf_sock_addr_set()
* The addrlen is exposed as u32 in bpf_sock_addr_kern
* Selftests are updated to use the new kfunc
* Selftests are now added as a new sock_addr test in prog_tests/
* Added BTF_KFUNC_HOOK_SOCK_ADDR for BPF_PROG_TYPE_CGROUP_SOCK_ADDR
* __cgroup_bpf_run_filter_sock_addr() now returns the modified addrlen

Changes since v1:

* Split into multiple patches instead of one single patch
* Added unix support for all socket address hooks instead of only connect()
* Switched approach to expose the socket address length to the bpf hook
instead of recalculating the socket address length in kernelspace to
properly support abstract unix socket addresses
* Modified socket address hook tests to calculate the socket address length
once and pass it around everywhere instead of recalculating the actual unix
socket address length on demand.
* Added some missing section name tests for getpeername()/getsockname()

This patch series extends the cgroup sockaddr hooks to include support for unix
sockets. To add support for unix sockets, struct bpf_sock_addr_kern is extended
to expose the socket address length to the bpf program. Along with that, a new
kfunc bpf_sock_addr_set_unix_addr() is added to safely allow modifying an
AF_UNIX sockaddr from bpf programs.

I intend to use these new hooks in systemd to reimplement the LogNamespace=
feature, which allows running multiple instances of systemd-journald to
process the logs of different services. systemd-journald also processes
syslog messages, so currently, using log namespaces means all services running
in the same log namespace have to live in the same private mount namespace
so that systemd can mount the journal namespace's associated syslog socket
over /dev/log to properly direct syslog messages from all services running
in that log namespace to the correct systemd-journald instance. We want to
relax this requirement so that processes running in disjoint mount namespaces
can still run in the same log namespace. To achieve this, we can use these
new hooks to rewrite the socket address of any connect(), sendto(), ...
syscalls to /dev/log to the socket address of the journal namespace's syslog
socket instead, which will transparently do the redirection without requiring
use of a mount namespace and mounting over /dev/log.

Aside from the above usecase, these hooks can more generally be used to
transparently redirect unix sockets to different addresses as required by
services.
====================

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:56 -07:00
Daan De Meyer
82ab6b505e selftests/bpf: Add tests for cgroup unix socket address hooks
These selftests are written in prog_tests style instead of adding
them to the existing test_sock_addr tests. Migrating the existing
sock addr tests to prog_tests style is left for future work. This
commit adds support for testing bind() sockaddr hooks, even though
there's no unix socket sockaddr hook for bind(). We leave this code
intact for when the INET and INET6 tests are migrated in the future
which do support intercepting bind().

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-10-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:55 -07:00
Daan De Meyer
af2752ed45 selftests/bpf: Make sure mount directory exists
The mount directory for the selftests cgroup tree might
not exist so let's make sure it does exist by creating
it ourselves if it doesn't exist.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-9-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:55 -07:00
Daan De Meyer
3243fef6a4 documentation/bpf: Document cgroup unix socket address hooks
Update the documentation to mention the new cgroup unix sockaddr
hooks.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-8-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:55 -07:00
Daan De Meyer
8b3cba987e bpftool: Add support for cgroup unix socket address hooks
Add the necessary plumbing to hook up the new cgroup unix sockaddr
hooks into bpftool.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20231011185113.140426-7-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:55 -07:00
Daan De Meyer
bf90438c78 libbpf: Add support for cgroup unix socket address hooks
Add the necessary plumbing to hook up the new cgroup unix sockaddr
hooks into libbpf.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-6-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:55 -07:00
Daan De Meyer
859051dd16 bpf: Implement cgroup sockaddr hooks for unix sockets
These hooks allows intercepting connect(), getsockname(),
getpeername(), sendmsg() and recvmsg() for unix sockets. The unix
socket hooks get write access to the address length because the
address length is not fixed when dealing with unix sockets and
needs to be modified when a unix socket address is modified by
the hook. Because abstract socket unix addresses start with a
NUL byte, we cannot recalculate the socket address in kernelspace
after running the hook by calculating the length of the unix socket
path using strlen().

These hooks can be used when users want to multiplex syscall to a
single unix socket to multiple different processes behind the scenes
by redirecting the connect() and other syscalls to process specific
sockets.

We do not implement support for intercepting bind() because when
using bind() with unix sockets with a pathname address, this creates
an inode in the filesystem which must be cleaned up. If we rewrite
the address, the user might try to clean up the wrong file, leaking
the socket in the filesystem where it is never cleaned up. Until we
figure out a solution for this (and a use case for intercepting bind()),
we opt to not allow rewriting the sockaddr in bind() calls.

We also implement recvmsg() support for connected streams so that
after a connect() that is modified by a sockaddr hook, any corresponding
recmvsg() on the connected socket can also be modified to make the
connected program think it is connected to the "intended" remote.

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-5-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:47 -07:00
Daan De Meyer
53e380d214 bpf: Add bpf_sock_addr_set_sun_path() to allow writing unix sockaddr from bpf
As prep for adding unix socket support to the cgroup sockaddr hooks,
let's add a kfunc bpf_sock_addr_set_sun_path() that allows modifying a unix
sockaddr from bpf. While this is already possible for AF_INET and AF_INET6,
we'll need this kfunc when we add unix socket support since modifying the
address for those requires modifying both the address and the sockaddr
length.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-4-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 16:29:25 -07:00
Daan De Meyer
fefba7d1ae bpf: Propagate modified uaddrlen from cgroup sockaddr programs
As prep for adding unix socket support to the cgroup sockaddr hooks,
let's propagate the sockaddr length back to the caller after running
a bpf cgroup sockaddr hook program. While not important for AF_INET or
AF_INET6, the sockaddr length is important when working with AF_UNIX
sockaddrs as the size of the sockaddr cannot be determined just from the
address family or the sockaddr's contents.

__cgroup_bpf_run_filter_sock_addr() is modified to take the uaddrlen as
an input/output argument. After running the program, the modified sockaddr
length is stored in the uaddrlen pointer.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-3-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 15:03:40 -07:00
Daan De Meyer
feba7b634e selftests/bpf: Add missing section name tests for getpeername/getsockname
These were missed when these hooks were first added so add them now
instead to make sure every sockaddr hook has a matching section name
test.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-2-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 13:24:18 -07:00
Martin KaFai Lau
1ef09e1281 Merge branch 'bpf: Fix src IP addr related limitation in bpf_*_fib_lookup()'
Martynas Pumputis says:

====================
The patchset fixes the limitation of bpf_*_fib_lookup() helper, which
prevents it from being used in BPF dataplanes with network interfaces
which have more than one IP addr. See the first patch for more details.
Thanks!

* v2->v3: Address Martin KaFai Lau's feedback
* v1->v2: Use IPv6 stubs to fix compilation when CONFIG_IPV6=m.
====================

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-09 16:28:37 -07:00
Martynas Pumputis
b0f7a8ca11 selftests/bpf: Add BPF_FIB_LOOKUP_SRC tests
This patch extends the existing fib_lookup test suite by adding two test
cases (for each IP family):

* Test source IP selection from the egressing netdev.
* Test source IP selection when an IP route has a preferred src IP addr.

Signed-off-by: Martynas Pumputis <m@lambda.lt>
Link: https://lore.kernel.org/r/20231007081415.33502-3-m@lambda.lt
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-09 16:28:37 -07:00
Martynas Pumputis
dab4e1f06c bpf: Derive source IP addr via bpf_*_fib_lookup()
Extend the bpf_fib_lookup() helper by making it to return the source
IPv4/IPv6 address if the BPF_FIB_LOOKUP_SRC flag is set.

For example, the following snippet can be used to derive the desired
source IP address:

    struct bpf_fib_lookup p = { .ipv4_dst = ip4->daddr };

    ret = bpf_skb_fib_lookup(skb, p, sizeof(p),
            BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH);
    if (ret != BPF_FIB_LKUP_RET_SUCCESS)
        return TC_ACT_SHOT;

    /* the p.ipv4_src now contains the source address */

The inability to derive the proper source address may cause malfunctions
in BPF-based dataplanes for hosts containing netdevs with more than one
routable IP address or for multi-homed hosts.

For example, Cilium implements packet masquerading in BPF. If an
egressing netdev to which the Cilium's BPF prog is attached has
multiple IP addresses, then only one [hardcoded] IP address can be used for
masquerading. This breaks connectivity if any other IP address should have
been selected instead, for example, when a public and private addresses
are attached to the same egress interface.

The change was tested with Cilium [1].

Nikolay Aleksandrov helped to figure out the IPv6 addr selection.

[1]: https://github.com/cilium/cilium/pull/28283

Signed-off-by: Martynas Pumputis <m@lambda.lt>
Link: https://lore.kernel.org/r/20231007081415.33502-2-m@lambda.lt
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-09 16:28:35 -07:00
Ian Rogers
1be84ca53c bpftool: Align bpf_load_and_run_opts insns and data
A C string lacks alignment so use aligned arrays to avoid potential
alignment problems. Switch to using sizeof (less 1 for the \0
terminator) rather than a hardcode size constant.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20231007044439.25171-2-irogers@google.com
2023-10-09 09:36:51 -07:00
Ian Rogers
23671f4dfd bpftool: Align output skeleton ELF code
libbpf accesses the ELF data requiring at least 8 byte alignment,
however, the data is generated into a C string that doesn't guarantee
alignment. Fix this by assigning to an aligned char array. Use sizeof
on the array, less one for the \0 terminator, rather than generating a
constant.

Fixes: a6cc6b34b9 ("bpftool: Provide a helper method for accessing skeleton's embedded ELF data")
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20231007044439.25171-1-irogers@google.com
2023-10-09 09:36:51 -07:00
David Vernet
0d7ae06860 selftests/bpf: Test pinning bpf timer to a core
Now that we support pinning a BPF timer to the current core, we should
test it with some selftests. This patch adds two new testcases to the
timer suite, which verifies that a BPF timer both with and without
BPF_F_TIMER_ABS, can be pinned to the calling core with BPF_F_TIMER_CPU_PIN.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20231004162339.200702-3-void@manifault.com
2023-10-09 16:29:06 +02:00
David Vernet
d6247ecb6c bpf: Add ability to pin bpf timer to calling CPU
BPF supports creating high resolution timers using bpf_timer_* helper
functions. Currently, only the BPF_F_TIMER_ABS flag is supported, which
specifies that the timeout should be interpreted as absolute time. It
would also be useful to be able to pin that timer to a core. For
example, if you wanted to make a subset of cores run without timer
interrupts, and only have the timer be invoked on a single core.

This patch adds support for this with a new BPF_F_TIMER_CPU_PIN flag.
When specified, the HRTIMER_MODE_PINNED flag is passed to
hrtimer_start(). A subsequent patch will update selftests to validate.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20231004162339.200702-2-void@manifault.com
2023-10-09 16:28:49 +02:00
Kees Cook
84cb9cbd91 bpf: Annotate struct bpf_stack_map with __counted_by
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle [1], add __counted_by for struct bpf_stack_map.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Link: https://lore.kernel.org/bpf/20231006201657.work.531-kees@kernel.org
2023-10-06 23:44:35 +02:00
Geliang Tang
fdd11c14c3 selftests/bpf: Add pairs_redir_to_connected helper
Extract duplicate code from these four functions

 unix_redir_to_connected()
 udp_redir_to_connected()
 inet_unix_redir_to_connected()
 unix_inet_redir_to_connected()

to generate a new helper pairs_redir_to_connected(). Create the
different socketpairs in these four functions, then pass the
socketpairs info to the new common helper to do the connections.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Link: https://lore.kernel.org/r/54bb28dcf764e7d4227ab160883931d2173f4f3d.1696588133.git.geliang.tang@suse.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-06 11:25:22 -07:00
Andrii Nakryiko
0af3aace5b selftests/bpf: Don't truncate #test/subtest field
We currently expect up to a three-digit number of tests and subtests, so:

  #999/999: some_test/some_subtest: ...

Is the largest test/subtest we can see. If we happen to cross into
1000s, current logic will just truncate everything after 7th character.
This patch fixes this truncate and allows to go way higher (up to 31
characters in total). We still nicely align test numbers:

  #60/66   core_reloc_btfgen/type_based___incompat:OK
  #60/67   core_reloc_btfgen/type_based___fn_wrong_args:OK
  #60/68   core_reloc_btfgen/type_id:OK
  #60/69   core_reloc_btfgen/type_id___missing_targets:OK
  #60/70   core_reloc_btfgen/enumval:OK

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20231006175744.3136675-3-andrii@kernel.org
2023-10-06 20:17:28 +02:00
Andrii Nakryiko
46475cc0dd selftests/bpf: Support building selftests in optimized -O2 mode
Add support for building selftests with -O2 level of optimization, which
allows more compiler warnings detection (like lots of potentially
uninitialized usage), but also is useful to have a faster-running test
for some CPU-intensive tests.

One can build optimized versions of libbpf and selftests by running:

  $ make RELEASE=1

There is a measurable speed up of about 10 seconds for me locally,
though it's mostly capped by non-parallelized serial tests. User CPU
time goes down by total 40 seconds, from 1m10s to 0m28s.

Unoptimized build (-O0)
=======================
Summary: 430/3544 PASSED, 25 SKIPPED, 4 FAILED

real    1m59.937s
user    1m10.877s
sys     3m14.880s

Optimized build (-O2)
=====================
Summary: 425/3543 PASSED, 25 SKIPPED, 9 FAILED

real    1m50.540s
user    0m28.406s
sys     3m13.198s

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20231006175744.3136675-2-andrii@kernel.org
2023-10-06 20:17:28 +02:00
Andrii Nakryiko
925a01577e selftests/bpf: Fix compiler warnings reported in -O2 mode
Fix a bunch of potentially unitialized variable usage warnings that are
reported by GCC in -O2 mode. Also silence overzealous stringop-truncation
class of warnings.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20231006175744.3136675-1-andrii@kernel.org
2023-10-06 20:17:28 +02:00
Yafang Shao
bc5bc309db bpf: Inherit system settings for CPU security mitigations
Currently, there exists a system-wide setting related to CPU security
mitigations, denoted as 'mitigations='. When set to 'mitigations=off', it
deactivates all optional CPU mitigations. Therefore, if we implement a
system-wide 'mitigations=off' setting, it should inherently bypass Spectre
v1 and Spectre v4 in the BPF subsystem.

Please note that there is also a more specific 'nospectre_v1' setting on
x86 and ppc architectures, though it is not currently exported. For the
time being, let's disregard more fine-grained options.

This idea emerged during our discussion about potential Spectre v1 attacks
with Luis [0].

  [0] https://lore.kernel.org/bpf/b4fc15f7-b204-767e-ebb9-fdb4233961fb@iogearbox.net

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <song@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Cc: Luis Gerhorst <gerhorst@cs.fau.de>
Link: https://lore.kernel.org/bpf/20231005084123.1338-1-laoar.shao@gmail.com
2023-10-06 20:16:44 +02:00
Akihiko Odaki
9c8c3fa3a5 bpf: Fix the comment for bpf_restore_data_end()
The comment used to say:
> Restore data saved by bpf_compute_data_pointers().

But bpf_compute_data_pointers() does not save the data;
bpf_compute_and_save_data_end() does.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20231005072137.29870-1-akihiko.odaki@daynix.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-05 22:33:50 -07:00
Geliang Tang
d549854bc5 selftests/bpf: Enable CONFIG_VSOCKETS in config
CONFIG_VSOCKETS is required by BPF selftests, otherwise we get errors
like this:

    ./test_progs:socket_loopback_reuseport:386: socket:
		Address family not supported by protocol
    socket_loopback_reuseport:FAIL:386
    ./test_progs:vsock_unix_redir_connectible:1496:
		vsock_socketpair_connectible() failed
    vsock_unix_redir_connectible:FAIL:1496

So this patch enables it in tools/testing/selftests/bpf/config.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Link: https://lore.kernel.org/r/472e73d285db2ea59aca9bbb95eb5d4048327588.1696490003.git.geliang.tang@suse.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-05 21:41:07 -07:00
Andrii Nakryiko
3157b7ce14 Merge branch 'selftest/bpf, riscv: Improved cross-building support'
Björn Töpel says:

====================
From: Björn Töpel <bjorn@rivosinc.com>

Yet another "more cross-building support for RISC-V" series.

An example how to invoke a gen_tar build:

  | make ARCH=riscv CROSS_COMPILE=riscv64-linux-gnu- CC=riscv64-linux-gnu-gcc \
  |    HOSTCC=gcc O=/workspace/kbuild FORMAT= \
  |    SKIP_TARGETS="arm64 ia64 powerpc sparc64 x86 sgx" -j $(($(nproc)-1)) \
  |    -C tools/testing/selftests gen_tar

Björn
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-10-04 13:37:56 -07:00
Björn Töpel
e096ab9d9f selftests/bpf: Add uprobe_multi to gen_tar target
The uprobe_multi program was not picked up for the gen_tar target. Fix
by adding it to TEST_GEN_FILES.

Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20231004122721.54525-4-bjorn@kernel.org
2023-10-04 13:37:41 -07:00
Björn Töpel
72fae63199 selftests/bpf: Enable lld usage for RISC-V
RISC-V has proper lld support. Use that, similar to what x86 does, for
urandom_read et al.

Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20231004122721.54525-3-bjorn@kernel.org
2023-10-04 13:37:41 -07:00
Björn Töpel
97a79e502e selftests/bpf: Add cross-build support for urandom_read et al
Some userland programs in the BPF test suite, e.g. urandom_read, is
missing cross-build support. Add cross-build support for these
programs

Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20231004122721.54525-2-bjorn@kernel.org
2023-10-04 13:36:50 -07:00
Andrii Nakryiko
cbcb199b7c Merge branch 'libbpf/selftests syscall wrapper fixes for RISC-V'
Björn Töpel says:

====================
From: Björn Töpel <bjorn@rivosinc.com>

Commit 08d0ce30e0 ("riscv: Implement syscall wrappers") introduced
some regressions in libbpf, and the kselftests BPF suite, which are
fixed with these three patches.

Note that there's an outstanding fix [1] for ftrace syscall tracing
which is also a fallout from the commit above.

Björn

[1] https://lore.kernel.org/linux-riscv/20231003182407.32198-1-alexghiti@rivosinc.com/

Alexandre Ghiti (1):
  libbpf: Fix syscall access arguments on riscv
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-10-04 13:19:47 -07:00
Björn Töpel
b55b775f03 selftests/bpf: Define SYS_NANOSLEEP_KPROBE_NAME for riscv
Add missing sys_nanosleep name for RISC-V, which is used by some tests
(e.g. attach_probe).

Fixes: 08d0ce30e0 ("riscv: Implement syscall wrappers")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-4-bjorn@kernel.org
2023-10-04 13:19:44 -07:00
Björn Töpel
0f2692ee43 selftests/bpf: Define SYS_PREFIX for riscv
SYS_PREFIX was missing for a RISC-V, which made a couple of kprobe
tests fail.

Add missing SYS_PREFIX for RISC-V.

Fixes: 08d0ce30e0 ("riscv: Implement syscall wrappers")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-3-bjorn@kernel.org
2023-10-04 13:19:39 -07:00
Alexandre Ghiti
8a412c5c1c libbpf: Fix syscall access arguments on riscv
Since commit 08d0ce30e0 ("riscv: Implement syscall wrappers"), riscv
selects ARCH_HAS_SYSCALL_WRAPPER so let's use the generic implementation
of PT_REGS_SYSCALL_REGS().

Fixes: 08d0ce30e0 ("riscv: Implement syscall wrappers")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-2-bjorn@kernel.org
2023-10-04 13:19:13 -07:00
Daniel Borkmann
93fb2776f4 Merge branch 'bpf-xsk-sh-umem'
Tushar Vyavahare says:

====================
Implement a test for the SHARED_UMEM feature in this patch set and make
necessary changes/improvements. Ensure that the framework now supports
different streams for different sockets.

v2->v3:
- Set the sock_num at the end of the while loop.
- Declare xsk at the top of the while loop.

v1->v2:
- Remove generate_mac_addresses() and generate mac addresses based on
  the number of sockets in __test_spec_init() function. [Magnus]
- Update Makefile to include find_bit.c for compiling xskxceiver.
- Add bitmap_full() function to verify all bits are set to break the
  while loop in the receive_pkts() and send_pkts() functions.
- Replace __test_and_set_bit() function with __set_bit() function.
- Add single return check for wait_for_tx_completion() function call.

Patch series summary:

1: Move the packet stream from the ifobject struct to the xsk_socket_info
   struct to enable the use of different streams for different sockets
   This will facilitate the sending and receiving of data from multiple
   sockets simultaneously using the SHARED_XDP_UMEM feature.

   It gives flexibility of send/recive individual traffic on particular
   socket.

2: Rename the header file to a generic name so that it can be used by all
   future XDP programs.

3: Move the src_mac and dst_mac fields from the ifobject structure to the
   xsk_socket_info structure to achieve per-socket MAC address assignment.
   Require this in order to steer traffic to various sockets in subsequent
   patches.

4: Improve the receive_pkt() function to enable it to receive packets from
   multiple sockets. Define a sock_num variable to iterate through all the
   sockets in the Rx path. Add nb_valid_entries to check that all the
   expected number of packets are received.

5: The pkt_set() function no longer needs the umem parameter. This commit
   removes the umem parameter from the pkt_set() function.

6: Iterate over all the sockets in the send pkts function. Update
   send_pkts() to handle multiple sockets for sending packets. Multiple TX
   sockets are utilized alternately based on the batch size for improve
   packet transmission.

7: Modify xsk_update_xskmap() to accept the index as an argument, enabling
   the addition of multiple sockets to xskmap.

8: Add a new test for testing shared umem feature. This is accomplished by
   adding a new XDP program and using the multiple sockets. The new XDP
   program redirects the packets based on the destination MAC address.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2023-10-04 15:26:18 +02:00
Tushar Vyavahare
6d198a89c0 selftests/xsk: Add a test for shared umem feature
Add a new test for testing shared umem feature. This is accomplished by
adding a new XDP program and using the multiple sockets.

The new XDP program redirects the packets based on the destination MAC
address.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-9-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
fc2cb86495 selftests/xsk: Modify xsk_update_xskmap() to accept the index as an argument
Modify xsk_update_xskmap() to accept the index as an argument, enabling
the addition of multiple sockets to xskmap.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-8-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
fd0815ae9b selftests/xsk: Iterate over all the sockets in the send pkts function
Update send_pkts() to handle multiple sockets for sending packets.
Multiple TX sockets are utilized alternately based on the batch size for
improve packet transmission.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-7-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
46e43786cc selftests/xsk: Remove unnecessary parameter from pkt_set() function call
The pkt_set() function no longer needs the umem parameter. This commit
removes the umem parameter from the pkt_set() function.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-6-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
8913e653e9 selftests/xsk: Iterate over all the sockets in the receive pkts function
Improve the receive_pkt() function to enable it to receive packets from
multiple sockets. Define a sock_num variable to iterate through all the
sockets in the Rx path. Add nb_valid_entries to check that all the
expected number of packets are received.

Revise the function __receive_pkts() to only inspect the receive ring
once, handle any received packets, and promptly return. Implement a bitmap
to store the value of number of sockets. Update Makefile to include
find_bit.c for compiling xskxceiver.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-5-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
985fd2145a selftests/xsk: Move src_mac and dst_mac to the xsk_socket_info
Move the src_mac and dst_mac fields from the ifobject structure to the
xsk_socket_info structure to achieve per-socket MAC address assignment.

Require this in order to steer traffic to various sockets in subsequent
patches.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-4-tushar.vyavahare@intel.com
2023-10-04 15:26:01 +02:00
Tushar Vyavahare
93ba112479 selftests/xsk: Rename xsk_xdp_metadata.h to xsk_xdp_common.h
Rename the header file to a generic name so that it can be used by all
future XDP programs. Ensure that the xsk_xdp_common.h header file includes
include guards.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-3-tushar.vyavahare@intel.com
2023-10-04 15:26:01 +02:00
Tushar Vyavahare
8367eb954e selftests/xsk: Move pkt_stream to the xsk_socket_info
Move the packet stream from the ifobject struct to the xsk_socket_info
struct to enable the use of different streams for different sockets. This
will facilitate the sending and receiving of data from multiple sockets
simultaneously using the SHARED_XDP_UMEM feature.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-2-tushar.vyavahare@intel.com
2023-10-04 15:26:01 +02:00
Hengqi Chen
2147c8d07e libbpf: Allow Golang symbols in uprobe secdef
Golang symbols in ELF files are different from C/C++
which contains special characters like '*', '(' and ')'.
With generics, things get more complicated, there are
symbols like:

  github.com/cilium/ebpf/internal.(*Deque[go.shape.interface { Format(fmt.State, int32); TypeName() string;github.com/cilium/ebpf/btf.copy() github.com/cilium/ebpf/btf.Type}]).Grow

Matching such symbols using `%m[^\n]` in sscanf, this
excludes newline which typically does not appear in ELF
symbols. This should work in most use-cases and also
work for unicode letters in identifiers. If newline do
show up in ELF symbols, users can still attach to such
symbol by specifying bpf_uprobe_opts::func_name.

A working example can be found at this repo ([0]).

  [0]: https://github.com/chenhengqi/libbpf-go-symbols

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230929155954.92448-1-hengqi.chen@gmail.com
2023-09-29 14:32:20 -07:00
Ruowen Qin
9e09b75079 samples/bpf: Add -fsanitize=bounds to userspace programs
The sanitizer flag, which is supported by both clang and gcc, would make
it easier to debug array index out-of-bounds problems in these programs.

Make the Makfile smarter to detect ubsan support from the compiler and
add the '-fsanitize=bounds' accordingly.

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jinghao Jia <jinghao@linux.ibm.com>
Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Signed-off-by: Ruowen Qin <ruowenq2@illinois.edu>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230927045030.224548-2-ruowenq2@illinois.edu
2023-09-28 09:31:05 -07:00
Andrii Nakryiko
0e73ef1d8c Merge branch 'bpf: Add missed stats for kprobes'
Jiri Olsa says:

====================
hi,
at the moment we can't retrieve the number of missed kprobe
executions and subsequent execution of BPF programs.

This patchset adds:
  - counting of missed execution on attach layer for:
    . kprobes attached through perf link (kprobe/ftrace)
    . kprobes attached through kprobe.multi link (fprobe)
  - counting of recursion_misses for BPF kprobe programs

It's still technically possible to create kprobe without perf link (using
SET_BPF perf ioctl) in which case we don't have a way to retrieve the kprobe's
'missed' count. However both libbpf and cilium/ebpf libraries use perf link
if it's available, and for old kernels without perf link support we can use
BPF program to retrieve the kprobe missed count.

v3 changes:
  - added acks [Song]
  - make test_missed not serial [Andrii]

Also available at:
  https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
  bpf/missed_stats

thanks,
jirka
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-09-25 16:37:53 -07:00
Jiri Olsa
85981e0f9e selftests/bpf: Add test for recursion counts of perf event link tracepoint
Adding selftest that puts kprobe on bpf_fentry_test1 that calls bpf_printk
and invokes bpf_trace_printk tracepoint. The bpf_trace_printk tracepoint
has test[234] programs attached to it.

Because kprobe execution goes through bpf_prog_active check, programs
attached to the tracepoint will fail the recursion check and increment the
recursion_misses stats.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-10-jolsa@kernel.org
2023-09-25 16:37:45 -07:00