diff options
| author | Nicholas Carlini <nicholas@carlini.com> | 2026-03-27 02:18:23 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-03-26 20:28:28 -0600 |
| commit | 5170efd9c344c68a8075dcb8ed38d3f8a60e7ed4 (patch) | |
| tree | 20f6e1cf42029b27502e1a1c857a06af13945e28 /io_uring | |
| parent | b59efde9e6c122207c16169d3d0deb623956eae9 (diff) | |
io_uring/fdinfo: fix OOB read in SQE_MIXED wrap check
__io_uring_show_fdinfo() iterates over pending SQEs and, for 128-byte
SQEs on an IORING_SETUP_SQE_MIXED ring, needs to detect when the second
half of the SQE would be past the end of the sq_sqes array. The current
check tests (++sq_head & sq_mask) == 0, but sq_head is only incremented
when a 128-byte SQE is encountered, not on every iteration. The actual
array index is sq_idx = (i + sq_head) & sq_mask, which can be sq_mask
(the last slot) while the wrap check passes.
Fix by checking sq_idx directly. Keep the sq_head increment so the loop
still skips the second half of the 128-byte SQE on the next iteration.
Fixes: 1cba30bf9fdd ("io_uring: add support for IORING_SETUP_SQE_MIXED")
Signed-off-by: Nicholas Carlini <nicholas@carlini.com>
Link: https://patch.msgid.link/20260327021823.3138396-1-nicholas@carlini.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/fdinfo.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c index 25c92ace18bd..c2d3e45544bb 100644 --- a/io_uring/fdinfo.c +++ b/io_uring/fdinfo.c @@ -119,12 +119,13 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) sq_idx); break; } - if ((++sq_head & sq_mask) == 0) { + if (sq_idx == sq_mask) { seq_printf(m, "%5u: corrupted sqe, wrapping 128B entry\n", sq_idx); break; } + sq_head++; i++; sqe128 = true; } |