Kernel/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-01-10 07:10:27 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

io_uring: fix refcounting with batched allocations at OOM

Browse Source 
In case of out of memory the second argument of percpu_ref_put_many() in
io_submit_sqes() may evaluate into "nr - (-EAGAIN)", that is clearly
wrong.

Fixes: 2b85edfc0c90 ("io_uring: batch getting pcpu references")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2020-01-25 22:34:01 +03:00 committed by Jens Axboe
parent 8cdf2193a3
commit 9466f43741
1 changed files with 5 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
fs/io_uring.c
View File

@ -4830,8 +4830,11 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
break; break;
} }
if (submitted != nr) if (unlikely(submitted != nr)) {
percpu_ref_put_many(&ctx->refs, nr - submitted); int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
percpu_ref_put_many(&ctx->refs, nr - ref_used);
}
if (link) if (link)
io_queue_link_head(link); io_queue_link_head(link);
if (statep) if (statep)