Smatch static checker warning:
fs/ksmbd/vfs.c:1040 ksmbd_vfs_fqar_lseek() warn: no lower bound on 'length'
fs/ksmbd/vfs.c:1041 ksmbd_vfs_fqar_lseek() warn: no lower bound on 'start'
Fix unexpected result that could caused from negative start and length.
Fixes: f44158485826 ("cifsd: add file operations")
Reported-by: Dan Carpenter <error27@xxxxxxxxx>
Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
---
v2:
- Move sanity check before ksmbd_lookup_fd_fast().
fs/ksmbd/smb2pdu.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index b7a420e0fcc4..540c24d7cf67 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -7450,13 +7450,16 @@ static int fsctl_query_allocated_ranges(struct ksmbd_work *work, u64 id,
if (in_count == 0)
return -EINVAL;
+ start = le64_to_cpu(qar_req->file_offset);
+ length = le64_to_cpu(qar_req->length);
+
+ if (start < 0 || length < 0)
+ return -EINVAL;
+
fp = ksmbd_lookup_fd_fast(work, id);
if (!fp)
return -ENOENT;
- start = le64_to_cpu(qar_req->file_offset);
- length = le64_to_cpu(qar_req->length);
-
ret = ksmbd_vfs_fqar_lseek(fp, start, length,
qar_rsp, in_count, out_count);
if (ret && ret != -E2BIG)
--
2.25.1
