From 29cd2927fb914cc53b5ba4f67d2b74695c994ba4 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 2 May 2023 14:59:10 -0400 Subject: [PATCH] SUNRPC: Fix encoding of accepted but unsuccessful RPC replies Jiri Slaby says: > I bisected to this ... as it breaks nfs3-only servers in 6.3. > I.e. /etc/nfs.conf containing: > [nfsd] > vers4=no > > The client sees: > mount("10.0.2.15:/tmp", "/mnt", "nfs", 0, "vers=4.2,addr=10.0.2.15,clientad"...) = -1 EIO (Input/output error) > write(2, "mount.nfs: mount system call fai"..., 45 > mount.nfs: mount system call failed for /mnt > > And the kernel says: > nfs4_discover_server_trunking unhandled error -5. Exiting with error EIO Reported-by: Jiri Slaby Link: https://bugzilla.suse.com/show_bug.cgi?id=1210995 Fixes: 4bcf0343e8a6 ("SUNRPC: Set rq_accept_statp inside ->accept methods") Tested-by: Jiri Slaby Signed-off-by: Chuck Lever --- net/sunrpc/svc.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 26367cf..43e3212 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1416,7 +1416,7 @@ err_bad_rpc: /* Only RPCv2 supported */ xdr_stream_encode_u32(xdr, RPC_VERSION); xdr_stream_encode_u32(xdr, RPC_VERSION); - goto sendit; + return 1; /* don't wrap */ err_bad_auth: dprintk("svc: authentication failed (%d)\n", @@ -1432,7 +1432,7 @@ err_bad_auth: err_bad_prog: dprintk("svc: unknown program %d\n", rqstp->rq_prog); serv->sv_stats->rpcbadfmt++; - xdr_stream_encode_u32(xdr, RPC_PROG_UNAVAIL); + *rqstp->rq_accept_statp = rpc_prog_unavail; goto sendit; err_bad_vers: @@ -1440,7 +1440,12 @@ err_bad_vers: rqstp->rq_vers, rqstp->rq_prog, progp->pg_name); serv->sv_stats->rpcbadfmt++; - xdr_stream_encode_u32(xdr, RPC_PROG_MISMATCH); + *rqstp->rq_accept_statp = rpc_prog_mismatch; + + /* + * svc_authenticate() has already added the verifier and + * advanced the stream just past rq_accept_statp. + */ xdr_stream_encode_u32(xdr, process.mismatch.lovers); xdr_stream_encode_u32(xdr, process.mismatch.hivers); goto sendit; @@ -1449,19 +1454,19 @@ err_bad_proc: svc_printk(rqstp, "unknown procedure (%d)\n", rqstp->rq_proc); serv->sv_stats->rpcbadfmt++; - xdr_stream_encode_u32(xdr, RPC_PROC_UNAVAIL); + *rqstp->rq_accept_statp = rpc_proc_unavail; goto sendit; err_garbage_args: svc_printk(rqstp, "failed to decode RPC header\n"); serv->sv_stats->rpcbadfmt++; - xdr_stream_encode_u32(xdr, RPC_GARBAGE_ARGS); + *rqstp->rq_accept_statp = rpc_garbage_args; goto sendit; err_system_err: serv->sv_stats->rpcbadfmt++; - xdr_stream_encode_u32(xdr, RPC_SYSTEM_ERR); + *rqstp->rq_accept_statp = rpc_system_err; goto sendit; } -- 2.7.4