udf: Check consistency of Space Bitmap Descriptor
commit
1e0d4adf17e7ef03281d7b16555e7c1508c8ed2d upstream.
Bits, which are related to Bitmap Descriptor logical blocks,
are not reset when buffer headers are allocated for them. As the
result, these logical blocks can be treated as free and
be used for other blocks.This can cause usage of one buffer header
for several types of data. UDF issues WARNING in this situation:
WARNING: CPU: 0 PID: 2703 at fs/udf/inode.c:2014
__udf_add_aext+0x685/0x7d0 fs/udf/inode.c:2014
RIP: 0010:__udf_add_aext+0x685/0x7d0 fs/udf/inode.c:2014
Call Trace:
udf_setup_indirect_aext+0x573/0x880 fs/udf/inode.c:1980
udf_add_aext+0x208/0x2e0 fs/udf/inode.c:2067
udf_insert_aext fs/udf/inode.c:2233 [inline]
udf_update_extents fs/udf/inode.c:1181 [inline]
inode_getblk+0x1981/0x3b70 fs/udf/inode.c:885
Found by Linux Verification Center (linuxtesting.org) with syzkaller.
[JK: Somewhat cleaned up the boundary checks]
Fixes:
1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Vladislav Efanov <VEfanov@ispras.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>