3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> commit c7848f69ec4a8c03732cde5c949bd2aa711a9f4b upstream. decode_op_hdr() cannot distinguish between an XDR decoding error and the perfectly valid errorcode NFS4ERR_IO. This is normally not a problem, but for the particular case of OPEN, we need to be able to increment the NFSv4 open sequence id when the server returns a valid response. Reported-by: J Bruce Fields <bfields@xxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20131204210356.GA19452@xxxxxxxxxxxx Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/nfs/nfs4xdr.c | 47 +++++++++++++++++++++++++++++++---------------- 1 file changed, 31 insertions(+), 16 deletions(-) --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -2955,7 +2955,8 @@ out_overflow: return -EIO; } -static int decode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected) +static bool __decode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected, + int *nfs_retval) { __be32 *p; uint32_t opnum; @@ -2965,19 +2966,32 @@ static int decode_op_hdr(struct xdr_stre if (unlikely(!p)) goto out_overflow; opnum = be32_to_cpup(p++); - if (opnum != expected) { - dprintk("nfs: Server returned operation" - " %d but we issued a request for %d\n", - opnum, expected); - return -EIO; - } + if (unlikely(opnum != expected)) + goto out_bad_operation; nfserr = be32_to_cpup(p); - if (nfserr != NFS_OK) - return nfs4_stat_to_errno(nfserr); - return 0; + if (nfserr == NFS_OK) + *nfs_retval = 0; + else + *nfs_retval = nfs4_stat_to_errno(nfserr); + return true; +out_bad_operation: + dprintk("nfs: Server returned operation" + " %d but we issued a request for %d\n", + opnum, expected); + *nfs_retval = -EREMOTEIO; + return false; out_overflow: print_overflow_msg(__func__, xdr); - return -EIO; + *nfs_retval = -EIO; + return false; +} + +static int decode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected) +{ + int retval; + + __decode_op_hdr(xdr, expected, &retval); + return retval; } /* Dummy routine */ @@ -4680,11 +4694,12 @@ static int decode_open(struct xdr_stream uint32_t savewords, bmlen, i; int status; - status = decode_op_hdr(xdr, OP_OPEN); - if (status != -EIO) - nfs_increment_open_seqid(status, res->seqid); - if (!status) - status = decode_stateid(xdr, &res->stateid); + if (!__decode_op_hdr(xdr, OP_OPEN, &status)) + return status; + nfs_increment_open_seqid(status, res->seqid); + if (status) + return status; + status = decode_stateid(xdr, &res->stateid); if (unlikely(status)) return status; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html