linux/kernel/bpf
Naveen N. Rao 0bcd484587 bpf: Guard against accessing NULL pt_regs in bpf_get_task_stack()
commit b992f01e66 upstream.

task_pt_regs() can return NULL on powerpc for kernel threads. This is
then used in __bpf_get_stack() to check for user mode, resulting in a
kernel oops. Guard against this by checking return value of
task_pt_regs() before trying to obtain the call chain.

Fixes: fa28dcb82a ("bpf: Introduce helper bpf_get_task_stack()")
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d5ef83c361cc255494afd15ff1b4fb02a36e1dcf.1641468127.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-01 17:26:59 +01:00
..
preload libbpf: Move BPF_SEQ_PRINTF and BPF_SNPRINTF to bpf_helpers.h 2021-05-26 10:45:41 -07:00
arraymap.c bpf: Fix potential race in tail call compatibility check 2021-10-26 12:37:28 -07:00
bpf_inode_storage.c bpf: Fix spelling mistakes 2021-05-24 21:13:05 -07:00
bpf_iter.c bpf: Refactor BPF_PROG_RUN into a function 2021-08-17 00:45:07 +02:00
bpf_local_storage.c bpf: Prevent deadlock from recursive bpf_task_storage_[get|delete] 2021-02-26 11:51:48 -08:00
bpf_lru_list.c bpf_lru_list: Read double-checked variable once without lock 2021-02-10 15:54:26 -08:00
bpf_lru_list.h bpf: Fix a typo "inacitve" -> "inactive" 2020-04-06 21:54:10 +02:00
bpf_lsm.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-06-17 11:54:56 -07:00
bpf_struct_ops_types.h bpf: tcp: Support tcp_congestion_ops in bpf 2020-01-09 08:46:18 -08:00
bpf_struct_ops.c bpf: Handle return value of BPF_PROG_TYPE_STRUCT_OPS prog 2021-09-14 11:09:50 -07:00
bpf_task_storage.c bpf: Consolidate task_struct BTF_ID declarations 2021-08-25 10:37:05 -07:00
btf.c bpf: Disallow BPF_LOG_KERNEL log level for bpf(BPF_BTF_LOAD) 2022-01-27 11:03:27 +01:00
cgroup.c bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs 2021-11-25 09:49:07 +01:00
core.c bpf: Fix potential race in tail call compatibility check 2021-10-26 12:37:28 -07:00
cpumap.c bpf: cpumap: Implement generic cpumap 2021-07-07 20:01:45 -07:00
devmap.c bpf, devmap: Exclude XDP broadcast to master device 2021-08-09 23:25:14 +02:00
disasm.c bpf: Relicense disassembler as GPL-2.0-only OR BSD-2-Clause 2021-09-02 14:49:23 +02:00
disasm.h bpf: Relicense disassembler as GPL-2.0-only OR BSD-2-Clause 2021-09-02 14:49:23 +02:00
dispatcher.c bpf: Remove bpf_image tree 2020-03-13 12:49:52 -07:00
hashtab.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-13 06:41:22 -07:00
helpers.c bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs 2021-11-25 09:49:07 +01:00
inode.c bpf: Fix mount source show for bpffs 2022-01-27 11:05:26 +01:00
Kconfig sock_map: Relax config dependency to CONFIG_NET 2021-07-15 18:17:49 -07:00
local_storage.c bpf: Increase supported cgroup storage value size 2021-07-27 15:59:29 -07:00
lpm_trie.c bpf: Allow RCU-protected lookups to happen from bh context 2021-06-24 19:41:15 +02:00
Makefile bpf: Enable task local storage for tracing programs 2021-02-26 11:51:47 -08:00
map_in_map.c bpf: Remember BTF of inner maps. 2021-07-15 22:31:10 +02:00
map_in_map.h bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
map_iter.c bpf: Implement link_query callbacks in map element iterators 2020-08-21 14:01:39 -07:00
net_namespace.c bpf: Add support for forced LINK_DETACH command 2020-08-01 20:38:28 -07:00
offload.c bpf, offload: Replace bitwise AND by logical AND in bpf_prog_offload_info_fill 2020-02-17 16:53:49 +01:00
percpu_freelist.c bpf: Use raw_spin_trylock() for pcpu_freelist_push/pop in NMI 2020-10-06 00:04:11 +02:00
percpu_freelist.h bpf: Use raw_spin_trylock() for pcpu_freelist_push/pop in NMI 2020-10-06 00:04:11 +02:00
prog_iter.c bpf: Refactor bpf_iter_reg to have separate seq_info member 2020-07-25 20:16:32 -07:00
queue_stack_maps.c bpf: Eliminate rlimit-based memory accounting for queue_stack_maps maps 2020-12-02 18:32:46 -08:00
reuseport_array.c bpf: Fix spelling mistakes 2021-05-24 21:13:05 -07:00
ringbuf.c bpf: Fix false positive kmemleak report in bpf_ringbuf_area_alloc() 2021-06-28 15:57:46 +02:00
stackmap.c bpf: Guard against accessing NULL pt_regs in bpf_get_task_stack() 2022-02-01 17:26:59 +01:00
syscall.c bpf: Fix toctou on read-only map's constant scalar tracking 2021-11-25 09:48:36 +01:00
sysfs_btf.c bpf: Load and verify kernel module BTFs 2020-11-10 15:25:53 -08:00
task_iter.c bpf: Consolidate task_struct BTF_ID declarations 2021-08-25 10:37:05 -07:00
tnum.c bpf, tnums: Provably sound, faster, and more precise algorithm for tnum_mul 2021-06-01 13:34:15 +02:00
trampoline.c bpf: Fixes possible race in update_prog_stats() for 32bit arches 2021-11-18 19:16:42 +01:00
verifier.c bpf: Mark PTR_TO_FUNC register initially with zero offset 2022-01-27 11:05:26 +01:00