From 345b4159a075b15dc4ae70f1db90fa8abf85d2e7 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 3 Jun 2021 16:52:22 -0400 Subject: lockd: Update the NLMv4 TEST arguments decoder to use struct xdr_stream Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- fs/lockd/xdr4.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 66 insertions(+), 6 deletions(-) (limited to 'fs') diff --git a/fs/lockd/xdr4.c b/fs/lockd/xdr4.c index d0960a8551f8..cf64794fdc1f 100644 --- a/fs/lockd/xdr4.c +++ b/fs/lockd/xdr4.c @@ -96,6 +96,32 @@ nlm4_decode_fh(__be32 *p, struct nfs_fh *f) return p + XDR_QUADLEN(f->size); } +/* + * NLM file handles are defined by specification to be a variable-length + * XDR opaque no longer than 1024 bytes. However, this implementation + * limits their length to the size of an NFSv3 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 > NFS_MAXFHSIZE) + return false; + + p = xdr_inline_decode(xdr, len); + if (!p) + return false; + fh->size = len; + memcpy(fh->data, p, len); + memset(fh->data + len, 0, sizeof(fh->data) - len); + + return true; +} + /* * Encode and decode owner handle */ @@ -135,6 +161,39 @@ nlm4_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; + u64 len, start; + s64 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_u64(xdr, &start) < 0) + return false; + if (xdr_stream_decode_u64(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 = s64_to_loff_t(start); + if (len == 0 || end < 0) + fl->fl_end = OFFSET_MAX; + else + fl->fl_end = s64_to_loff_t(end); + + return true; +} + /* * Encode result of a TEST/TEST_MSG call */ @@ -189,19 +248,20 @@ nlm4svc_decode_void(struct svc_rqst *rqstp, __be32 *p) int nlm4svc_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 = nlm4_decode_cookie(p, &argp->cookie))) + if (!svcxdr_decode_cookie(xdr, &argp->cookie)) return 0; - - exclusive = ntohl(*p++); - if (!(p = nlm4_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 v1.2.3-59-g8ed1b