This is a note to let you know that I've just added the patch titled
more bio_map_user_iov() leak fixes
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
more-bio_map_user_iov-leak-fixes.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 2b04e8f6bbb196cab4b232af0f8d48ff2c7a8058 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Date: Sat, 23 Sep 2017 15:51:23 -0400
Subject: more bio_map_user_iov() leak fixes
From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
commit 2b04e8f6bbb196cab4b232af0f8d48ff2c7a8058 upstream.
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: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
Fixed conflicts.
Intended for v4.4.y. Does not apply to v3.18.y or older kernels.
block/bio.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
--- a/block/bio.c
+++ b/block/bio.c
@@ -1268,6 +1268,7 @@ struct bio *bio_map_user_iov(struct requ
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;
@@ -1312,7 +1313,12 @@ struct bio *bio_map_user_iov(struct requ
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;
}
@@ -1374,10 +1380,8 @@ struct bio *bio_map_user_iov(struct requ
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);
Patches currently in stable-queue which might be from viro@xxxxxxxxxxxxxxxxxx are
queue-4.4/more-bio_map_user_iov-leak-fixes.patch