Commit ce51f63e authored by Peilin Ye's avatar Peilin Ye Committed by David S. Miller
Browse files

net/smc: Prevent kernel-infoleak in __smc_diag_dump() 



__smc_diag_dump() is potentially copying uninitialized kernel stack memory
into socket buffers, since the compiler may leave a 4-byte hole near the
beginning of `struct smcd_diag_dmbinfo`. Fix it by initializing `dinfo`
with memset().

Fixes: 4b1b7d3b ("net/smc: add SMC-D diag support")
Suggested-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarPeilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: default avatarUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3e659a82

net/smc/smc_diag.c

+9 −7
Original line number Diff line number Diff line
@@ -170,13 +170,15 @@ static int __smc_diag_dump(struct sock *sk, struct sk_buff *skb, 
	    (req->diag_ext & (1 << (SMC_DIAG_DMBINFO - 1))) &&

	    !list_empty(&smc->conn.lgr->list)) {

		struct smc_connection *conn = &smc->conn;

		struct smcd_diag_dmbinfo dinfo = {

			.linkid = *((u32 *)conn->lgr->id),

			.peer_gid = conn->lgr->peer_gid,

			.my_gid = conn->lgr->smcd->local_gid,

			.token = conn->rmb_desc->token,

			.peer_token = conn->peer_token

		};

		struct smcd_diag_dmbinfo dinfo;



		memset(&dinfo, 0, sizeof(dinfo));



		dinfo.linkid = *((u32 *)conn->lgr->id);

		dinfo.peer_gid = conn->lgr->peer_gid;

		dinfo.my_gid = conn->lgr->smcd->local_gid;

		dinfo.token = conn->rmb_desc->token;

		dinfo.peer_token = conn->peer_token;



		if (nla_put(skb, SMC_DIAG_DMBINFO, sizeof(dinfo), &dinfo) < 0)

			goto errout;