commit | a7537d805f405f86617355ac6fab708fc2a4d95a | [log] [tgz] |
---|---|---|
author | Jiri Olsa <[email protected]> | Wed Jan 03 20:05:46 2024 +0100 |
committer | Oleksandr Tymoshenko <[email protected]> | Fri Mar 22 21:23:49 2024 +0000 |
tree | 4cf5fa207641e78dd82324859ccc5867c3d639e4 | |
parent | 579d6c05f2712f139a03ecc741dbd7fac6e2d03d [diff] |
bpf: Fix re-attachment branch in bpf_tracing_prog_attach commit 715d82ba636cb3629a6e18a33bb9dbe53f9936ee upstream. The following case can cause a crash due to missing attach_btf: 1) load rawtp program 2) load fentry program with rawtp as target_fd 3) create tracing link for fentry program with target_fd = 0 4) repeat 3 In the end we have: - prog->aux->dst_trampoline == NULL - tgt_prog == NULL (because we did not provide target_fd to link_create) - prog->aux->attach_btf == NULL (the program was loaded with attach_prog_fd=X) - the program was loaded for tgt_prog but we have no way to find out which one BUG: kernel NULL pointer dereference, address: 0000000000000058 Call Trace: <TASK> ? __die+0x20/0x70 ? page_fault_oops+0x15b/0x430 ? fixup_exception+0x22/0x330 ? exc_page_fault+0x6f/0x170 ? asm_exc_page_fault+0x22/0x30 ? bpf_tracing_prog_attach+0x279/0x560 ? btf_obj_id+0x5/0x10 bpf_tracing_prog_attach+0x439/0x560 __sys_bpf+0x1cf4/0x2de0 __x64_sys_bpf+0x1c/0x30 do_syscall_64+0x41/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 Return -EINVAL in this situation. BUG=b/330305990 TEST=presubmit RELEASE_NOTE=Fixed CVE-2024-26591 in the Linux kernel. cos-patch: security-moderate Fixes: f3a95075549e0 ("bpf: Allow trampoline re-attach for tracing and lsm programs") Cc: [email protected] Signed-off-by: Jiri Olsa <[email protected]> Acked-by: Jiri Olsa <[email protected]> Acked-by: Song Liu <[email protected]> Signed-off-by: Dmitrii Dolgov <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Change-Id: If83346f53b2ff3b0e0167f1ed221eb2ac3dcd5ba Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/67791 Reviewed-by: Anil Altinay <[email protected]> Tested-by: Cusky Presubmit Bot <[email protected]>