Files
linux/kernel
Vincent Donnefort e743527c5b 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it can allocate a reader page with an outdated order.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: bce761d757 ("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>
2026-08-14 13:19:12 -04:00
..
2026-06-02 15:36:06 +02:00
2025-10-29 10:29:54 +01:00
2026-01-26 19:07:13 -08:00