linux-stable/fs/ntfs
Desmond Cheong Zhi Xi 00f00f5db8 ntfs: fix validity check for file name attribute
commit d98e4d9541 upstream.

When checking the file name attribute, we want to ensure that it fits
within the bounds of ATTR_RECORD.  To do this, we should check that (attr
record + file name offset + file name length) < (attr record + attr record
length).

However, the original check did not include the file name offset in the
calculation.  This means that corrupted on-disk metadata might not caught
by the incorrect file name check, and lead to an invalid memory access.

An example can be seen in the crash report of a memory corruption error
found by Syzbot:
https://syzkaller.appspot.com/bug?id=a1a1e379b225812688566745c3e2f7242bffc246

Adding the file name offset to the validity check fixes this error and
passes the Syzbot reproducer test.

Link: https://lkml.kernel.org/r/20210614050540.289494-1-desmondcheongzx@gmail.com
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Reported-by: syzbot+213ac8bb98f7f4420840@syzkaller.appspotmail.com
Tested-by: syzbot+213ac8bb98f7f4420840@syzkaller.appspotmail.com
Acked-by: Anton Altaparmakov <anton@tuxera.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-20 16:15:39 +02:00
..
aops.c
aops.h
attrib.c
attrib.h
bitmap.c
bitmap.h
collate.c
collate.h
compress.c
debug.c
debug.h
dir.c
dir.h
endian.h
file.c
index.c
index.h
inode.c ntfs: fix validity check for file name attribute 2021-07-20 16:15:39 +02:00
inode.h
Kconfig
layout.h
lcnalloc.c
lcnalloc.h
logfile.c
logfile.h
Makefile
malloc.h
mft.c
mft.h
mst.c
namei.c
ntfs.h
quota.c
quota.h
runlist.c
runlist.h
super.c
sysctl.c
sysctl.h
time.h
types.h
unistr.c
upcase.c
usnjrnl.c
usnjrnl.h
volume.h