diff options
| author | Jeffrey Mitchell <jeffrey.mitchell@starlab.io> | 2020-08-05 12:23:19 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-21 13:05:37 +0200 |
| commit | 75cf7f895f563e14c82c1aeea0362dc155b5baf3 (patch) | |
| tree | 8139dd63f64f253399144b1183aae9343a5997b4 | |
| parent | d09d6dca89e948ddddf2b0c509b05b8cd71626de (diff) | |
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.c | 2 | ||||
| -rw-r--r-- | fs/nfs/nfs4xdr.c | 6 |
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; |