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author | Daniel Borkmann <daniel@iogearbox.net> | 2024-09-13 21:17:49 +0200 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2024-09-13 13:17:56 -0700 |
commit | 18752d73c1898fd001569195ba4b0b8c43255f4a (patch) | |
tree | f6895f9f0abcb467d9d19af936b1645cf5c5aba1 /kernel/bpf/syscall.c | |
parent | 32556ce93bc45c730829083cb60f95a2728ea48b (diff) |
bpf: Improve check_raw_mode_ok test for MEM_UNINIT-tagged types
When checking malformed helper function signatures, also take other argument
types into account aside from just ARG_PTR_TO_UNINIT_MEM.
This concerns (formerly) ARG_PTR_TO_{INT,LONG} given uninitialized memory can
be passed there, too.
The func proto sanity check goes back to commit 435faee1aae9 ("bpf, verifier:
add ARG_PTR_TO_RAW_STACK type"), and its purpose was to detect wrong func protos
which had more than just one MEM_UNINIT-tagged type as arguments.
The reason more than one is currently not supported is as we mark stack slots with
STACK_MISC in check_helper_call() in case of raw mode based on meta.access_size to
allow uninitialized stack memory to be passed to helpers when they just write into
the buffer.
Probing for base type as well as MEM_UNINIT tagging ensures that other types do not
get missed (as it used to be the case for ARG_PTR_TO_{INT,LONG}).
Fixes: 57c3bb725a3d ("bpf: Introduce ARG_PTR_TO_{INT,LONG} arg types")
Reported-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://lore.kernel.org/r/20240913191754.13290-4-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf/syscall.c')
0 files changed, 0 insertions, 0 deletions