This is a note to let you know that I've just added the patch titled NFSD: Update NFSv2 diropargs decoding to use struct xdr_stream to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfsd-update-nfsv2-diropargs-decoding-to-use-struct-x.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 712d7d181910fb6bfdbcb837c68296061789bd36 Author: Chuck Lever <chuck.lever@xxxxxxxxxx> Date: Mon Oct 19 14:33:24 2020 -0400 NFSD: Update NFSv2 diropargs decoding to use struct xdr_stream [ Upstream commit 6d742c1864c18f143ea2031f1ed66bcd8f4812de ] Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c index 7b33093f8d8b4..00a7db8548ebf 100644 --- a/fs/nfsd/nfsxdr.c +++ b/fs/nfsd/nfsxdr.c @@ -86,6 +86,38 @@ decode_filename(__be32 *p, char **namp, unsigned int *lenp) return p; } +static bool +svcxdr_decode_filename(struct xdr_stream *xdr, char **name, unsigned int *len) +{ + u32 size, i; + __be32 *p; + char *c; + + if (xdr_stream_decode_u32(xdr, &size) < 0) + return false; + if (size == 0 || size > NFS_MAXNAMLEN) + return false; + p = xdr_inline_decode(xdr, size); + if (!p) + return false; + + *len = size; + *name = (char *)p; + for (i = 0, c = *name; i < size; i++, c++) + if (*c == '\0' || *c == '/') + return false; + + return true; +} + +static bool +svcxdr_decode_diropargs(struct xdr_stream *xdr, struct svc_fh *fhp, + char **name, unsigned int *len) +{ + return svcxdr_decode_fhandle(xdr, fhp) && + svcxdr_decode_filename(xdr, name, len); +} + static __be32 * decode_sattr(__be32 *p, struct iattr *iap, struct user_namespace *userns) { @@ -234,13 +266,10 @@ nfssvc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p) int nfssvc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p) { + struct xdr_stream *xdr = &rqstp->rq_arg_stream; struct nfsd_diropargs *args = rqstp->rq_argp; - if (!(p = decode_fh(p, &args->fh)) - || !(p = decode_filename(p, &args->name, &args->len))) - return 0; - - return xdr_argsize_check(rqstp, p); + return svcxdr_decode_diropargs(xdr, &args->fh, &args->name, &args->len); } int