Commit 6df164e2 authored by Lei Lu's avatar Lei Lu Committed by Chuck Lever
Browse files

sunrpc: fix null pointer dereference on zero-length checksum 



In xdr_stream_decode_opaque_auth(), zero-length checksum.len causes
checksum.data to be set to NULL. This triggers a NPD when accessing
checksum.data in gss_krb5_verify_mic_v2(). This patch ensures that
the value of checksum.len is not less than XDR_UNIT.

Fixes: 0653028e ("SUNRPC: Convert gss_verify_header() to use xdr_stream")
Cc: stable@kernel.org
Signed-off-by: default avatarLei Lu <llfamsec@gmail.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 07e27ad1

net/sunrpc/auth_gss/svcauth_gss.c

+1 −1
Original line number Diff line number Diff line
@@ -724,7 +724,7 @@ svcauth_gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci, 
		rqstp->rq_auth_stat = rpc_autherr_badverf;

		return SVC_DENIED;

	}

	if (flavor != RPC_AUTH_GSS) {

	if (flavor != RPC_AUTH_GSS || checksum.len < XDR_UNIT) {

		rqstp->rq_auth_stat = rpc_autherr_badverf;

		return SVC_DENIED;

	}