nfsd: fix rare symlink decoding bug

[firefly-linux-kernel-4.4.55.git] / fs / nfsd / nfs4proc.c

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 59c319528cf931c02ea21ee0c9ccc1e7b81fb136..8f029db5d271d6c77e6bf22a3cf3e3924ce27f08 100644 (file)
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -430,12 +430,12 @@ nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                                goto out;
                        break;
                case NFS4_OPEN_CLAIM_PREVIOUS:
-                       open->op_openowner->oo_flags |= NFS4_OO_CONFIRMED;
                        status = nfs4_check_open_reclaim(&open->op_clientid,
                                                         cstate->minorversion,
                                                         nn);
                        if (status)
                                goto out;
+                       open->op_openowner->oo_flags |= NFS4_OO_CONFIRMED;
                case NFS4_OPEN_CLAIM_FH:
                case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
                        status = do_open_fhandle(rqstp, cstate, open);
@@ -445,7 +445,6 @@ nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                        break;
                case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
                case NFS4_OPEN_CLAIM_DELEGATE_PREV:
-                       open->op_openowner->oo_flags |= NFS4_OO_CONFIRMED;
                        dprintk("NFSD: unsupported OPEN claim type %d\n",
                                open->op_claim_type);
                        status = nfserr_notsupp;
@@ -618,15 +617,6 @@ nfsd4_create(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 
        switch (create->cr_type) {
        case NF4LNK:
-               /* ugh! we have to null-terminate the linktext, or
-                * vfs_symlink() will choke.  it is always safe to
-                * null-terminate by brute force, since at worst we
-                * will overwrite the first byte of the create namelen
-                * in the XDR buffer, which has already been extracted
-                * during XDR decode.
-                */
-               create->cr_linkname[create->cr_linklen] = 0;
-
                status = nfsd_symlink(rqstp, &cstate->current_fh,
                                      create->cr_name, create->cr_namelen,
                                      create->cr_linkname, create->cr_linklen,
@@ -1261,13 +1251,13 @@ static void svcxdr_init_encode(struct svc_rqst *rqstp,
        xdr->buf = buf;
        xdr->iov = head;
        xdr->p   = head->iov_base + head->iov_len;
-       xdr->end = head->iov_base + PAGE_SIZE - 2 * RPC_MAX_AUTH_SIZE;
+       xdr->end = head->iov_base + PAGE_SIZE - rqstp->rq_auth_slack;
        /* Tail and page_len should be zero at this point: */
        buf->len = buf->head[0].iov_len;
        xdr->scratch.iov_len = 0;
-       xdr->page_ptr = buf->pages;
+       xdr->page_ptr = buf->pages - 1;
        buf->buflen = PAGE_SIZE * (1 + rqstp->rq_page_end - buf->pages)
-               - 2 * RPC_MAX_AUTH_SIZE;
+               - rqstp->rq_auth_slack;
 }
 
 /*
@@ -1291,11 +1281,8 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
        xdr_reserve_space(&resp->xdr, 8 + args->taglen);
        resp->taglen = args->taglen;
        resp->tag = args->tag;
-       resp->opcnt = 0;
        resp->rqstp = rqstp;
        cstate->minorversion = args->minorversion;
-       cstate->replay_owner = NULL;
-       cstate->session = NULL;
        fh_init(current_fh, NFS4_FHSIZE);
        fh_init(save_fh, NFS4_FHSIZE);
        /*
@@ -1465,6 +1452,49 @@ static inline u32 nfsd4_create_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op
                + nfs4_fattr_bitmap_maxsz) * sizeof(__be32);
 }
 
+/*
+ * Note since this is an idempotent operation we won't insist on failing
+ * the op prematurely if the estimate is too large.  We may turn off splice
+ * reads unnecessarily.
+ */
+static inline u32 nfsd4_getattr_rsize(struct svc_rqst *rqstp,
+                                     struct nfsd4_op *op)
+{
+       u32 *bmap = op->u.getattr.ga_bmval;
+       u32 bmap0 = bmap[0], bmap1 = bmap[1], bmap2 = bmap[2];
+       u32 ret = 0;
+
+       if (bmap0 & FATTR4_WORD0_ACL)
+               return svc_max_payload(rqstp);
+       if (bmap0 & FATTR4_WORD0_FS_LOCATIONS)
+               return svc_max_payload(rqstp);
+
+       if (bmap1 & FATTR4_WORD1_OWNER) {
+               ret += IDMAP_NAMESZ + 4;
+               bmap1 &= ~FATTR4_WORD1_OWNER;
+       }
+       if (bmap1 & FATTR4_WORD1_OWNER_GROUP) {
+               ret += IDMAP_NAMESZ + 4;
+               bmap1 &= ~FATTR4_WORD1_OWNER_GROUP;
+       }
+       if (bmap0 & FATTR4_WORD0_FILEHANDLE) {
+               ret += NFS4_FHSIZE + 4;
+               bmap0 &= ~FATTR4_WORD0_FILEHANDLE;
+       }
+       if (bmap2 & FATTR4_WORD2_SECURITY_LABEL) {
+               ret += NFSD4_MAX_SEC_LABEL_LEN + 12;
+               bmap2 &= ~FATTR4_WORD2_SECURITY_LABEL;
+       }
+       /*
+        * Largest of remaining attributes are 16 bytes (e.g.,
+        * supported_attributes)
+        */
+       ret += 16 * (hweight32(bmap0) + hweight32(bmap1) + hweight32(bmap2));
+       /* bitmask, length */
+       ret += 20;
+       return ret;
+}
+
 static inline u32 nfsd4_link_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
 {
        return (op_encode_hdr_size + op_encode_change_info_maxsz)
@@ -1500,13 +1530,14 @@ static inline u32 nfsd4_read_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
 
 static inline u32 nfsd4_readdir_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
 {
+       u32 maxcount = svc_max_payload(rqstp);
        u32 rlen = op->u.readdir.rd_maxcount;
 
-       if (rlen > PAGE_SIZE)
-               rlen = PAGE_SIZE;
+       if (rlen > maxcount)
+               rlen = maxcount;
 
-       return (op_encode_hdr_size + op_encode_verifier_maxsz)
-                * sizeof(__be32) + rlen;
+       return (op_encode_hdr_size + op_encode_verifier_maxsz +
+               XDR_QUADLEN(rlen)) * sizeof(__be32);
 }
 
 static inline u32 nfsd4_remove_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
@@ -1521,6 +1552,12 @@ static inline u32 nfsd4_rename_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op
                + op_encode_change_info_maxsz) * sizeof(__be32);
 }
 
+static inline u32 nfsd4_sequence_rsize(struct svc_rqst *rqstp,
+                                      struct nfsd4_op *op)
+{
+       return NFS4_MAX_SESSIONID_LEN + 20;
+}
+
 static inline u32 nfsd4_setattr_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
 {
        return (op_encode_hdr_size + nfs4_fattr_bitmap_maxsz) * sizeof(__be32);
@@ -1602,6 +1639,7 @@ static struct nfsd4_operation nfsd4_ops[] = {
        [OP_GETATTR] = {
                .op_func = (nfsd4op_func)nfsd4_getattr,
                .op_flags = ALLOWED_ON_ABSENT_FS,
+               .op_rsize_bop = nfsd4_getattr_rsize,
                .op_name = "OP_GETATTR",
        },
        [OP_GETFH] = {