From 2fd0c67aabcf0f8821450b00ee511faa0b7761bf Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 3 Jun 2021 16:51:04 -0400 Subject: lockd: Update the NLMv1 TEST arguments decoder to use struct xdr_stream Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- fs/lockd/xdr.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 66 insertions(+), 6 deletions(-) (limited to 'fs/lockd') diff --git a/fs/lockd/xdr.c b/fs/lockd/xdr.c index 8be42a23679e..56982edd4766 100644 --- a/fs/lockd/xdr.c +++ b/fs/lockd/xdr.c @@ -98,6 +98,33 @@ nlm_decode_fh(__be32 *p, struct nfs_fh *f) return p + XDR_QUADLEN(NFS2_FHSIZE); } +/* + * NLM file handles are defined by specification to be a variable-length + * XDR opaque no longer than 1024 bytes. However, this implementation + * constrains their length to exactly the length of an NFSv2 file + * handle. + */ +static bool +svcxdr_decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh) +{ + __be32 *p; + u32 len; + + if (xdr_stream_decode_u32(xdr, &len) < 0) + return false; + if (len != NFS2_FHSIZE) + return false; + + p = xdr_inline_decode(xdr, len); + if (!p) + return false; + fh->size = NFS2_FHSIZE; + memcpy(fh->data, p, len); + memset(fh->data + NFS2_FHSIZE, 0, sizeof(fh->data) - NFS2_FHSIZE); + + return true; +} + /* * Encode and decode owner handle */ @@ -143,6 +170,38 @@ nlm_decode_lock(__be32 *p, struct nlm_lock *lock) return p; } +static bool +svcxdr_decode_lock(struct xdr_stream *xdr, struct nlm_lock *lock) +{ + struct file_lock *fl = &lock->fl; + s32 start, len, end; + + if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len)) + return false; + if (!svcxdr_decode_fhandle(xdr, &lock->fh)) + return false; + if (!svcxdr_decode_owner(xdr, &lock->oh)) + return false; + if (xdr_stream_decode_u32(xdr, &lock->svid) < 0) + return false; + if (xdr_stream_decode_u32(xdr, &start) < 0) + return false; + if (xdr_stream_decode_u32(xdr, &len) < 0) + return false; + + locks_init_lock(fl); + fl->fl_flags = FL_POSIX; + fl->fl_type = F_RDLCK; + end = start + len - 1; + fl->fl_start = s32_to_loff_t(start); + if (len == 0 || end < 0) + fl->fl_end = OFFSET_MAX; + else + fl->fl_end = s32_to_loff_t(end); + + return true; +} + /* * Encode result of a TEST/TEST_MSG call */ @@ -192,19 +251,20 @@ nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p) int nlmsvc_decode_testargs(struct svc_rqst *rqstp, __be32 *p) { + struct xdr_stream *xdr = &rqstp->rq_arg_stream; struct nlm_args *argp = rqstp->rq_argp; - u32 exclusive; + u32 exclusive; - if (!(p = nlm_decode_cookie(p, &argp->cookie))) + if (!svcxdr_decode_cookie(xdr, &argp->cookie)) return 0; - - exclusive = ntohl(*p++); - if (!(p = nlm_decode_lock(p, &argp->lock))) + if (xdr_stream_decode_bool(xdr, &exclusive) < 0) + return 0; + if (!svcxdr_decode_lock(xdr, &argp->lock)) return 0; if (exclusive) argp->lock.fl.fl_type = F_WRLCK; - return xdr_argsize_check(rqstp, p); + return 1; } int -- cgit