Commit ac6ad7a8 authored by Colin Ian King's avatar Colin Ian King Committed by Steve French
Browse files

cifs: fix dereference on ses before it is null checked 



The assignment of pointer server dereferences pointer ses, however,
this dereference occurs before ses is null checked and hence we
have a potential null pointer dereference.  Fix this by only
dereferencing ses after it has been null checked.

Addresses-Coverity: ("Dereference before null check")
Fixes: 2808c6639104 ("cifs: add new debugging macro cifs_server_dbg")
Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent afe6f653

fs/cifs/smb2pdu.c

+8 −3
Original line number Diff line number Diff line
@@ -2759,8 +2759,10 @@ SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid, 
	else

		return -EIO;



	if (!ses)

		return -EIO;

	server = ses->server;

	if (!ses || !(server))

	if (!server)

		return -EIO;



	if (smb3_encryption_required(tcon))
@@ -3058,13 +3060,16 @@ query_info(const unsigned int xid, struct cifs_tcon *tcon, 
	int rc = 0;

	int resp_buftype = CIFS_NO_BUFFER;

	struct cifs_ses *ses = tcon->ses;

	struct TCP_Server_Info *server = ses->server;

	struct TCP_Server_Info *server;

	int flags = 0;

	bool allocated = false;



	cifs_dbg(FYI, "Query Info\n");



	if (!ses || !(server))

	if (!ses)

		return -EIO;

	server = ses->server;

	if (!server)

		return -EIO;



	if (smb3_encryption_required(tcon))

fs/cifs/transport.c

+2 −1
Original line number Diff line number Diff line
@@ -1242,12 +1242,13 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses, 
	struct kvec iov = { .iov_base = in_buf, .iov_len = len };

	struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };

	struct cifs_credits credits = { .value = 1, .instance = 0 };

	struct TCP_Server_Info *server = ses->server;

	struct TCP_Server_Info *server;



	if (ses == NULL) {

		cifs_dbg(VFS, "Null smb session\n");

		return -EIO;

	}

	server = ses->server;

	if (server == NULL) {

		cifs_dbg(VFS, "Null tcp session\n");

		return -EIO;

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