diff options
| author | Vincent Donnefort <vdonnefort@google.com> | 2026-08-13 14:11:47 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2026-08-14 13:19:12 -0400 |
| commit | e743527c5bfdceda1095bc0a9e596e2aebb6a9c3 (patch) | |
| tree | cc3acbcc7af8df80b285d2d5d3e12d08b431e8e7 /kernel/scs.c | |
| parent | 8a5f63637890f03177146efddaba5ec7a1b4d61f (diff) | |
ring-buffer: Fix subbuf resize race with ring_buffer_alloc_read_page()
ring_buffer_alloc_read_page() is racy with ring_buffer_subbuf_order_set,
it can allocate a reader page with an outdated order. This isn't a big
issue, the user can still re-allocate a new reader page and try again.
However, what is more problematic is if the value of subbuf_order
changes in the middle of ring_buffer_alloc_read_page(). In that case,
bpage->order might not match the actual allocated memory.
Use bpage->order for the allocation to prevent this race.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260813131152.3589632-6-vdonnefort@google.com
Fixes: bce761d75745 ("ring-buffer: Read and write to ring buffers with custom sub buffer size")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/scs.c')
0 files changed, 0 insertions, 0 deletions