[PATCH OLK-5.10] ksmbd: fix Out-of-Bounds Read in ksmbd_vfs_stream_read - Kernel

2 Jan 2025

From: Jordy Zomer jordyzomer@google.com
mainline inclusion
from mainline-v6.10-rc2
commit fc342cf86e2dc4d2edb0fc2ff5e28b6c7845adb9
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBEAPD
CVE: CVE-2024-56627
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
--------------------------------
An offset from client could be a negative value, It could lead
to an out-of-bounds read from the stream_buf.
Note that this issue is coming when setting
'vfs objects = streams_xattr parameter' in ksmbd.conf.
Cc: stable@vger.kernel.org # v5.15+
Reported-by: Jordy Zomer jordyzomer@google.com
Signed-off-by: Jordy Zomer jordyzomer@google.com
Signed-off-by: Namjae Jeon linkinjeon@kernel.org
Signed-off-by: Steve French stfrench@microsoft.com
Conflicts:
    fs/ksmbd/smb2pdu.c
    fs/smb/server/smb2pdu.c
[Conflicts due to ksmbd rename to smb/server]
Signed-off-by: Long Li leo.lilong@huawei.com
---
 fs/ksmbd/smb2pdu.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index f104de64493b..b6194837028a 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -6319,6 +6319,10 @@ int smb2_read(struct ksmbd_work *work)
    }
offset = le64_to_cpu(req->Offset);
+	if (offset < 0) {
+		err = -EINVAL;
+		goto out;
+	}
    length = le32_to_cpu(req->Length);
    mincount = le32_to_cpu(req->MinimumCount);
-- 
2.39.2


    