linux-sg2042/fs/squashfs
Phillip Lougher d6e621de1f squashfs: fix divide error in calculate_skip()
Sysbot has reported a "divide error" which has been identified as being
caused by a corrupted file_size value within the file inode.  This value
has been corrupted to a much larger value than expected.

Calculate_skip() is passed i_size_read(inode) >> msblk->block_log.  Due to
the file_size value corruption this overflows the int argument/variable in
that function, leading to the divide error.

This patch changes the function to use u64.  This will accommodate any
unexpectedly large values due to corruption.

The value returned from calculate_skip() is clamped to be never more than
SQUASHFS_CACHED_BLKS - 1, or 7.  So file_size corruption does not lead to
an unexpectedly large return result here.

Link: https://lkml.kernel.org/r/20210507152618.9447-1-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Reported-by: <syzbot+e8f781243ce16ac2f962@syzkaller.appspotmail.com>
Reported-by: <syzbot+7b98870d4fec9447b951@syzkaller.appspotmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-14 19:41:32 -07:00
..
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
block.c block: rename BIO_MAX_PAGES to BIO_MAX_VECS 2021-03-11 07:47:48 -07:00
cache.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
decompressor.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
decompressor.h squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
decompressor_multi.c squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
decompressor_multi_percpu.c Merge branch 'akpm' (patches from Andrew) 2020-06-02 12:21:36 -07:00
decompressor_single.c squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
dir.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
export.c squashfs: fix inode lookup sanity checks 2021-03-25 09:22:55 -07:00
file.c squashfs: fix divide error in calculate_skip() 2021-05-14 19:41:32 -07:00
file_cache.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
file_direct.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
fragment.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
id.c squashfs: fix xattr id and id lookup sanity checks 2021-03-25 09:22:55 -07:00
inode.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
lz4_wrapper.c squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
lzo_wrapper.c squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
namei.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
page_actor.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
page_actor.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
squashfs.h squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
squashfs_fs.h squashfs: fix inode lookup sanity checks 2021-03-25 09:22:55 -07:00
squashfs_fs_i.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
squashfs_fs_sb.h squashfs: add more sanity checks in id lookup 2021-02-09 17:26:44 -08:00
super.c squashfs: add more sanity checks in id lookup 2021-02-09 17:26:44 -08:00
symlink.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
xattr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 35 2019-05-24 17:27:11 +02:00
xattr.h squashfs: add more sanity checks in id lookup 2021-02-09 17:26:44 -08:00
xattr_id.c squashfs: fix xattr id and id lookup sanity checks 2021-03-25 09:22:55 -07:00
xz_wrapper.c squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
zlib_wrapper.c squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00
zstd_wrapper.c squashfs: migrate from ll_rw_block usage to BIO 2020-06-02 10:59:05 -07:00