5.4-stable review patch. If anyone has any objections, please let me know.
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From: Keith Busch kbusch@kernel.org
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 --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1256,7 +1256,7 @@ static int io_import_fixed(struct io_rin */ 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;