5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever <chuck.lever@xxxxxxxxxx> [ Upstream commit c3d2a04f05c590303c125a176e6e43df4a436fdb ] Replace the check for buffer over/underflow with a helper that is commonly used for this purpose. The helper also sets xdr->nwords correctly after successfully linearizing the symlink argument into the stream's scratch buffer. Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/nfsd/nfs3xdr.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c index 0293b8d65f10f..71e32cf288854 100644 --- a/fs/nfsd/nfs3xdr.c +++ b/fs/nfsd/nfs3xdr.c @@ -616,8 +616,6 @@ nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, struct xdr_stream *xdr) { struct nfsd3_symlinkargs *args = rqstp->rq_argp; struct kvec *head = rqstp->rq_arg.head; - struct kvec *tail = rqstp->rq_arg.tail; - size_t remaining; if (!svcxdr_decode_diropargs3(xdr, &args->ffh, &args->fname, &args->flen)) return false; @@ -626,16 +624,10 @@ nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, struct xdr_stream *xdr) if (xdr_stream_decode_u32(xdr, &args->tlen) < 0) return false; - /* request sanity */ - remaining = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len; - remaining -= xdr_stream_pos(xdr); - if (remaining < xdr_align_size(args->tlen)) - return false; - - args->first.iov_base = xdr->p; + /* symlink_data */ args->first.iov_len = head->iov_len - xdr_stream_pos(xdr); - - return true; + args->first.iov_base = xdr_inline_decode(xdr, args->tlen); + return args->first.iov_base != NULL; } bool -- 2.43.0