Ksawlii/kernel_samsung_a53x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

io_uring: fix off-by one bvec index

Browse source 
commit d6fef34ee4d102be448146f24caf96d7b4a05401 upstream.

If the offset equals the bv_len of the first registered bvec, then the
request does not include any of that first bvec. Skip it so that drivers
don't have to deal with a zero length bvec, which was observed to break
NVMe's PRP list creation.

Cc: stable@vger.kernel.org
Fixes: bd11b3a391e3 ("io_uring: don't use iov_iter_advance() for fixed buffers")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20231120221831.2646460-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Keith Busch 2023-11-20 14:18:31 -08:00 committed by Ksawlii
parent d318782267
commit dd73cf26da
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
io_uring/io_uring.c
View file

@ -3159,7 +3159,7 @@ static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter
*/
const struct bio_vec *bvec = imu->bvec;
if (offset <= bvec->bv_len) {
if (offset < bvec->bv_len) {
iov_iter_advance(iter, offset);
} else {
unsigned long seg_skip;