Merge branch 'for-3.16' of git://linux-nfs.org/~bfields/linux
Pull nfsd bugfixes from Bruce Fields:
"By coincidence, two NFSv4 symlink bugs, one introduced in the 3.16 xdr
encoding rewrite, the other a decoding bug that I think we've had
since the start but that just doesn't trigger very often"
* 'for-3.16' of git://linux-nfs.org/~bfields/linux:
nfs: fix nfs4d readlink truncated packet
nfsd: fix rare symlink decoding bug
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 6851b00..8f029db 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -617,15 +617,6 @@
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,
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 83baf2b..2fc7abe 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -600,7 +600,18 @@
READ_BUF(4);
create->cr_linklen = be32_to_cpup(p++);
READ_BUF(create->cr_linklen);
- SAVEMEM(create->cr_linkname, create->cr_linklen);
+ /*
+ * The VFS will want a null-terminated string, and
+ * null-terminating in place isn't safe since this might
+ * end on a page boundary:
+ */
+ create->cr_linkname =
+ kmalloc(create->cr_linklen + 1, GFP_KERNEL);
+ if (!create->cr_linkname)
+ return nfserr_jukebox;
+ memcpy(create->cr_linkname, p, create->cr_linklen);
+ create->cr_linkname[create->cr_linklen] = '\0';
+ defer_free(argp, kfree, create->cr_linkname);
break;
case NF4BLK:
case NF4CHR:
@@ -3267,7 +3278,7 @@
wire_count = htonl(maxcount);
write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
- xdr_truncate_encode(xdr, length_offset + 4 + maxcount);
+ xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
if (maxcount & 3)
write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
&zero, 4 - (maxcount&3));