forked from luck/tmp_suning_uos_patched
squashfs: fix length field overlap check in metadata reading
This is a regression introduced by the "migrate from ll_rw_block usage
to BIO" patch.
Squashfs packs structures on byte boundaries, and due to that the length
field (of the metadata block) may not be fully in the current block.
The new code rewrote and introduced a faulty check for that edge case.
Fixes: 93e72b3c61
("squashfs: migrate from ll_rw_block usage to BIO")
Reported-by: Bernd Amend <bernd.amend@gmail.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Adrien Schildknecht <adrien+dev@schischi.me>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Daniel Rosenberg <drosen@google.com>
Link: http://lkml.kernel.org/r/20200717195536.16069-1-phillip@squashfs.org.uk
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
e57942c563
commit
2910c59fd0
|
@ -175,7 +175,7 @@ int squashfs_read_data(struct super_block *sb, u64 index, int length,
|
||||||
/* Extract the length of the metadata block */
|
/* Extract the length of the metadata block */
|
||||||
data = page_address(bvec->bv_page) + bvec->bv_offset;
|
data = page_address(bvec->bv_page) + bvec->bv_offset;
|
||||||
length = data[offset];
|
length = data[offset];
|
||||||
if (offset <= bvec->bv_len - 1) {
|
if (offset < bvec->bv_len - 1) {
|
||||||
length |= data[offset + 1] << 8;
|
length |= data[offset + 1] << 8;
|
||||||
} else {
|
} else {
|
||||||
if (WARN_ON_ONCE(!bio_next_segment(bio, &iter_all))) {
|
if (WARN_ON_ONCE(!bio_next_segment(bio, &iter_all))) {
|
||||||
|
|
Loading…
Reference in New Issue
Block a user