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 10:53:07 +0200 |
| commit | db61fb8278925f54ccb0172471164aeb56ec6537 (patch) | |
| tree | b9dfb5b9a5dc675c55a1d4f2bd541c13cf0ca2aa | |
| parent | fc7ce1fecea444afe8d4cb8d8bfc030e66536089 (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 566afcc36adb..ca1702cefb85 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -4916,8 +4916,6 @@ 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 15cd9db6d616..28c1b765e444 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -4158,7 +4158,11 @@ static int decode_attr_security_label(struct xdr_stream *xdr, uint32_t *bitmap, goto out_overflow; 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; |