summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJeffrey Mitchell <jeffrey.mitchell@starlab.io>2020-08-05 12:23:19 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-08-21 13:05:37 +0200
commit75cf7f895f563e14c82c1aeea0362dc155b5baf3 (patch)
tree8139dd63f64f253399144b1183aae9343a5997b4
parentd09d6dca89e948ddddf2b0c509b05b8cd71626de (diff)
downloadlinux-stable-75cf7f895f563e14c82c1aeea0362dc155b5baf3.tar.gz
linux-stable-75cf7f895f563e14c82c1aeea0362dc155b5baf3.tar.bz2
linux-stable-75cf7f895f563e14c82c1aeea0362dc155b5baf3.zip
nfs: Fix getxattr kernel panic and memory overflow
[ Upstream commit b4487b93545214a9db8cbf32e86411677b0cca21 ] Move the buffer size check to decode_attr_security_label() before memcpy() Only call memcpy() if the buffer is large enough Fixes: aa9c2669626c ("NFS: Client implementation of Labeled-NFS") Signed-off-by: Jeffrey Mitchell <jeffrey.mitchell@starlab.io> [Trond: clean up duplicate test of label->len != 0] Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r--fs/nfs/nfs4proc.c2
-rw-r--r--fs/nfs/nfs4xdr.c6
2 files changed, 5 insertions, 3 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 1a1bd2fe6e98..d0cb827b72cf 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5811,8 +5811,6 @@ static int _nfs4_get_security_label(struct inode *inode, void *buf,
return ret;
if (!(fattr.valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL))
return -ENOENT;
- if (buflen < label.len)
- return -ERANGE;
return 0;
}
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 7c0ff1a3b591..677751bc3a33 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -4169,7 +4169,11 @@ static int decode_attr_security_label(struct xdr_stream *xdr, uint32_t *bitmap,
return -EIO;
if (len < NFS4_MAXLABELLEN) {
if (label) {
- memcpy(label->label, p, len);
+ if (label->len) {
+ if (label->len < len)
+ return -ERANGE;
+ memcpy(label->label, p, len);
+ }
label->len = len;
label->pi = pi;
label->lfs = lfs;