From f8870b9b75afb77986bc65940a231d54068ff2b1 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Thu, 28 May 2026 15:32:11 -0400 Subject: [PATCH] SUNRPC: Guard svcauth_gss_release() dispatch on rq_auth_stat svcauth_gss_release() reads gc_proc and switches on gc_svc before consulting rq_auth_stat. On the SVC_DENIED path after a failed svcauth_gss_accept(), those fields may hold stale values from a prior request or uninitialized slab residue: svcauth_gss_accept() allocates gss_svc_data with non-zeroing kmalloc and clears only gsd_databody_offset and rsci per request, not clcred. Because RPC_GSS_PROC_DATA is zero, a zeroed or stale-zero gc_proc passes the existing guard and falls through into the gc_svc switch, which can dispatch to svcauth_gss_wrap_integ() or svcauth_gss_wrap_priv(). Both wrap helpers call svcauth_gss_prepare_to_wrap() before any rsci->mechctx dereference, and that helper already returns early when rq_auth_stat is not rpc_auth_ok, so the downstream NULL dereference is blocked. The dispatch itself remains structurally wrong: it reads scalars that the caller has no contract to have initialized after a failed authentication. Mirror the existing rq_auth_stat gate in svcauth_gss_prepare_to_wrap() one frame up, so svcauth_gss_release() skips the clcred dispatch entirely when authentication has not succeeded. The cleanup tail that releases rq_client, rq_gssclient, cr_group_info, and rsci still runs. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Chris Mason Reviewed-by: Jeff Layton Link: https://patch.msgid.link/20260528-tier2-v1-4-d026a1415e0b@oracle.com Signed-off-by: Chuck Lever --- net/sunrpc/auth_gss/svcauth_gss.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index 8e8aceb31270..4eb537410cb5 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -1944,6 +1944,8 @@ svcauth_gss_release(struct svc_rqst *rqstp) if (!gsd) goto out; + if (rqstp->rq_auth_stat != rpc_auth_ok) + goto out; gc = &gsd->clcred; if (gc->gc_proc != RPC_GSS_PROC_DATA) goto out;