diff mbox series

[4/6] ksmbd: smb2: Allow messages padded to 8byte boundary

Message ID 20230505151108.5911-4-linkinjeon@kernel.org
State New
Headers show
Series [1/6] ksmbd: fix global-out-of-bounds in smb2_find_context_vals | expand

Commit Message

Namjae Jeon May 5, 2023, 3:11 p.m. UTC 
From: Gustav Johansson <gustajo@axis.com>

clc length is now accepted to <= 8 less than length,
rather than < 8.

Solve issues on some of Axis's smb clients which send
messages where clc length is 8 bytes less than length.

The specific client was running kernel 4.19.217 with
smb dialect 3.0.2 on armv7l.

Signed-off-by: Gustav Johansson <gustajo@axis.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
---
 fs/ksmbd/smb2misc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/fs/ksmbd/smb2misc.c b/fs/ksmbd/smb2misc.c
index fbdde426dd01..0ffe663b7590 100644
--- a/fs/ksmbd/smb2misc.c
+++ b/fs/ksmbd/smb2misc.c
@@ -416,8 +416,11 @@  int ksmbd_smb2_check_message(struct ksmbd_work *work)
 
 		/*
 		 * Allow a message that padded to 8byte boundary.
+		 * Linux 4.19.217 with smb 3.0.2 are sometimes
+		 * sending messages where the cls_len is exactly
+		 * 8 bytes less than len.
 		 */
-		if (clc_len < len && (len - clc_len) < 8)
+		if (clc_len < len && (len - clc_len) <= 8)
 			goto validate_credit;
 
 		pr_err_ratelimited(