diff options
| author | ZhangPeng <zhangpeng362@huawei.com> | 2022-12-02 03:00:38 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-12-11 19:30:19 -0800 |
| commit | c53ed55cb275344086e32a7080a6b19cb183650b (patch) | |
| tree | 6636774fb923e3af59166906ac725890e38c2e66 /fs/hfs | |
| parent | 8d824e69d9f3fa3121b2dda25053bae71e2460d2 (diff) | |
hfs: Fix OOB Write in hfs_asc2mac
Syzbot reported a OOB Write bug:
loop0: detected capacity change from 0 to 64
==================================================================
BUG: KASAN: slab-out-of-bounds in hfs_asc2mac+0x467/0x9a0
fs/hfs/trans.c:133
Write of size 1 at addr ffff88801848314e by task syz-executor391/3632
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
print_address_description+0x74/0x340 mm/kasan/report.c:284
print_report+0x107/0x1f0 mm/kasan/report.c:395
kasan_report+0xcd/0x100 mm/kasan/report.c:495
hfs_asc2mac+0x467/0x9a0 fs/hfs/trans.c:133
hfs_cat_build_key+0x92/0x170 fs/hfs/catalog.c:28
hfs_lookup+0x1ab/0x2c0 fs/hfs/dir.c:31
lookup_open fs/namei.c:3391 [inline]
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x10e6/0x2df0 fs/namei.c:3710
do_filp_open+0x264/0x4f0 fs/namei.c:3740
If in->len is much larger than HFS_NAMELEN(31) which is the maximum
length of an HFS filename, a OOB write could occur in hfs_asc2mac(). In
that case, when the dst reaches the boundary, the srclen is still
greater than 0, which causes a OOB write.
Fix this by adding a check on dstlen in while() before writing to dst
address.
Link: https://lkml.kernel.org/r/20221202030038.1391945-1-zhangpeng362@huawei.com
Fixes: 328b92278650 ("[PATCH] hfs: NLS support")
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Reported-by: <syzbot+dc3b1cf9111ab5fe98e7@syzkaller.appspotmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs/hfs')
| -rw-r--r-- | fs/hfs/trans.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/hfs/trans.c b/fs/hfs/trans.c index 39f5e343bf4d..fdb0edb8a607 100644 --- a/fs/hfs/trans.c +++ b/fs/hfs/trans.c @@ -109,7 +109,7 @@ void hfs_asc2mac(struct super_block *sb, struct hfs_name *out, const struct qstr if (nls_io) { wchar_t ch; - while (srclen > 0) { + while (srclen > 0 && dstlen > 0) { size = nls_io->char2uni(src, srclen, &ch); if (size < 0) { ch = '?'; |