From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.
===============
[ Upstream commit 2b04e8f6bbb196cab4b232af0f8d48ff2c7a8058 ]
we need to take care of failure exit as well - pages already
in bio should be dropped by analogue of bio_unmap_pages(),
since their refcounts had been bumped only once per reference
in bio.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
block/bio.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index d9cf77c6a847..f90b2abe2fa7 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1290,6 +1290,7 @@ struct bio *bio_map_user_iov(struct request_queue *q,
int ret, offset;
struct iov_iter i;
struct iovec iov;
+ struct bio_vec *bvec;
iov_for_each(iov, i, *iter) {
unsigned long uaddr = (unsigned long) iov.iov_base;
@@ -1334,7 +1335,12 @@ struct bio *bio_map_user_iov(struct request_queue *q,
ret = get_user_pages_fast(uaddr, local_nr_pages,
(iter->type & WRITE) != WRITE,
&pages[cur_page]);
- if (ret < local_nr_pages) {
+ if (unlikely(ret < local_nr_pages)) {
+ for (j = cur_page; j < page_limit; j++) {
+ if (!pages[j])
+ break;
+ put_page(pages[j]);
+ }
ret = -EFAULT;
goto out_unmap;
}
@@ -1396,10 +1402,8 @@ struct bio *bio_map_user_iov(struct request_queue *q,
return bio;
out_unmap:
- for (j = 0; j < nr_pages; j++) {
- if (!pages[j])
- break;
- page_cache_release(pages[j]);
+ bio_for_each_segment_all(bvec, bio, j) {
+ put_page(bvec->bv_page);
}
out:
kfree(pages);
--
2.14.1