Su Yue a6ab66eb85 btrfs: tree-checker: use u64 for item data end to avoid overflow ... User reported there is an array-index-out-of-bounds access while mounting the crafted image: [350.411942 ] loop0: detected capacity change from 0 to 262144 [350.427058 ] BTRFS: device fsid a62e00e8-e94e-4200-8217-12444de93c2e devid 1 transid 8 /dev/loop0 scanned by systemd-udevd (1044) [350.428564 ] BTRFS info (device loop0): disk space caching is enabled [350.428568 ] BTRFS info (device loop0): has skinny extents [350.429589 ] [350.429619 ] UBSAN: array-index-out-of-bounds in fs/btrfs/struct-funcs.c:161:1 [350.429636 ] index 1048096 is out of range for type 'page *[16]' [350.429650 ] CPU: 0 PID: 9 Comm: kworker/u8:1 Not tainted 5.16.0-rc4 [350.429652 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014 [350.429653 ] Workqueue: btrfs-endio-meta btrfs_work_helper [btrfs] [350.429772 ] Call Trace: [350.429774 ] <TASK> [350.429776 ] dump_stack_lvl+0x47/0x5c [350.429780 ] ubsan_epilogue+0x5/0x50 [350.429786 ] __ubsan_handle_out_of_bounds+0x66/0x70 [350.429791 ] btrfs_get_16+0xfd/0x120 [btrfs] [350.429832 ] check_leaf+0x754/0x1a40 [btrfs] [350.429874 ] ? filemap_read+0x34a/0x390 [350.429878 ] ? load_balance+0x175/0xfc0 [350.429881 ] validate_extent_buffer+0x244/0x310 [btrfs] [350.429911 ] btrfs_validate_metadata_buffer+0xf8/0x100 [btrfs] [350.429935 ] end_bio_extent_readpage+0x3af/0x850 [btrfs] [350.429969 ] ? newidle_balance+0x259/0x480 [350.429972 ] end_workqueue_fn+0x29/0x40 [btrfs] [350.429995 ] btrfs_work_helper+0x71/0x330 [btrfs] [350.430030 ] ? __schedule+0x2fb/0xa40 [350.430033 ] process_one_work+0x1f6/0x400 [350.430035 ] ? process_one_work+0x400/0x400 [350.430036 ] worker_thread+0x2d/0x3d0 [350.430037 ] ? process_one_work+0x400/0x400 [350.430038 ] kthread+0x165/0x190 [350.430041 ] ? set_kthread_struct+0x40/0x40 [350.430043 ] ret_from_fork+0x1f/0x30 [350.430047 ] </TASK> [350.430047 ] [350.430077 ] BTRFS warning (device loop0): bad eb member start: ptr 0xffe20f4e start 20975616 member offset 4293005178 size 2 btrfs check reports: corrupt leaf: root=3 block=20975616 physical=20975616 slot=1, unexpected item end, have 4294971193 expect 3897 The first slot item offset is 4293005033 and the size is 1966160. In check_leaf, we use btrfs_item_end() to check item boundary versus extent_buffer data size. However, return type of btrfs_item_end() is u32. (u32)(4293005033 + 1966160) == 3897, overflow happens and the result 3897 equals to leaf data size reasonably. Fix it by use u64 variable to store item data end in check_leaf() to avoid u32 overflow. This commit does solve the invalid memory access showed by the stack trace. However, its metadata profile is DUP and another copy of the leaf is fine. So the image can be mounted successfully. But when umount is called, the ASSERT btrfs_mark_buffer_dirty() will be triggered because the only node in extent tree has 0 item and invalid owner. It's solved by another commit "btrfs: check extent buffer owner against the owner rootid". Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215299 Reported-by: Wenqing Liu <wenqingliu0120@gmail.com> CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Su Yue <l@damenly.su> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>		2022-03-02 16:52:32 +01:00
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9p
adfs
affs
afs
autofs
befs
bfs
btrfs	btrfs: tree-checker: use u64 for item data end to avoid overflow	2022-03-02 16:52:32 +01:00
cachefiles
ceph
cifs
coda
configfs
cramfs
crypto
debugfs
devpts
dlm
ecryptfs
efivarfs
efs
erofs
exfat
exportfs
ext2
ext4
f2fs
fat
freevxfs
fscache
fuse
gfs2
hfs
hfsplus
hostfs
hpfs
hugetlbfs
iomap
isofs
jbd2
jffs2
jfs
kernfs
ksmbd
lockd
minix
netfs
nfs
nfs_common
nfsd
nilfs2
nls
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squashfs
sysfs
sysv
tracefs
ubifs
udf
ufs
unicode
vboxsf
verity
xfs
zonefs
aio.c
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf.c
binfmt_elf_fdpic.c
binfmt_flat.c
binfmt_misc.c
binfmt_script.c
buffer.c
char_dev.c
compat_binfmt_elf.c
coredump.c
d_path.c
dax.c
dcache.c
direct-io.c
drop_caches.c
eventfd.c
eventpoll.c
exec.c
fcntl.c
fhandle.c
file.c
file_table.c
filesystems.c
fs-writeback.c
fs_context.c
fs_parser.c
fs_pin.c
fs_struct.c
fs_types.c
fsopen.c
init.c
inode.c
internal.h
io-wq.c
io-wq.h
io_uring.c
ioctl.c
Kconfig
Kconfig.binfmt
kernel_read_file.c
libfs.c
locks.c
Makefile
mbcache.c
mount.h
mpage.c
namei.c
namespace.c
no-block.c
nsfs.c
open.c
pipe.c
pnode.c
pnode.h
posix_acl.c
proc_namespace.c
read_write.c
readdir.c
remap_range.c
select.c
seq_file.c
signalfd.c
splice.c
stack.c
stat.c
statfs.c
super.c
sync.c
timerfd.c
userfaultfd.c
utimes.c
xattr.c