#syz test
a incorrectly formatted chunk may decompress into
more than LZNT_CHUNK_SIZE bytes and a index out of bounds
will occur in s_max_off.
Signed-off-by: Andrew Ballance <andrewjballance@xxxxxxxxx>
---
fs/ntfs3/lznt.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/ntfs3/lznt.c b/fs/ntfs3/lznt.c
index 4aae598d6d88..fdc9b2ebf341 100644
--- a/fs/ntfs3/lznt.c
+++ b/fs/ntfs3/lznt.c
@@ -236,6 +236,9 @@ static inline ssize_t decompress_chunk(u8 *unc, u8 *unc_end, const u8 *cmpr,
/* Do decompression until pointers are inside range. */
while (up < unc_end && cmpr < cmpr_end) {
+ // return err if more than LZNT_CHUNK_SIZE bytes are written
+ if (up - unc > LZNT_CHUNK_SIZE)
+ return -EINVAL;
/* Correct index */
while (unc + s_max_off[index] < up)
index += 1;
--
2.45.0
