diff mbox series

[v2] ksmbd: add low bound validation to FSCTL_QUERY_ALLOCATED_RANGES

Message ID 20230307130150.5188-1-linkinjeon@kernel.org (mailing list archive)
State New, archived
Headers show
Series [v2] ksmbd: add low bound validation to FSCTL_QUERY_ALLOCATED_RANGES | expand

Commit Message

Namjae Jeon March 7, 2023, 1:01 p.m. UTC
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@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
---
 v2:
  - Move sanity check before ksmbd_lookup_fd_fast().

 fs/ksmbd/smb2pdu.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Sergey Senozhatsky March 8, 2023, 4:57 a.m. UTC | #1
On (23/03/07 22:01), Namjae Jeon wrote:
> 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@gmail.com>
> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
diff mbox series

Patch

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)