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| author | Dan Carpenter <dan.carpenter@oracle.com> | 2018-09-10 14:12:07 +0300 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2018-09-12 09:32:07 -0500 |
| commit | 2d204ee9d671327915260071c19350d84344e096 (patch) | |
| tree | d1ef8c358f51282c7fc382be90af5662872ac882 /fs | |
| parent | 56446f218af1133c802dad8e9e116f07f381846c (diff) | |
| download | linux-2d204ee9d671327915260071c19350d84344e096.tar.gz linux-2d204ee9d671327915260071c19350d84344e096.tar.bz2 linux-2d204ee9d671327915260071c19350d84344e096.zip | |
cifs: integer overflow in in SMB2_ioctl()
The "le32_to_cpu(rsp->OutputOffset) + *plen" addition can overflow and
wrap around to a smaller value which looks like it would lead to an
information leak.
Fixes: 4a72dafa19ba ("SMB2 FSCTL and IOCTL worker function")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/cifs/smb2pdu.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 6f0e6b42599c..f54d07bda067 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -2459,14 +2459,14 @@ SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid, /* We check for obvious errors in the output buffer length and offset */ if (*plen == 0) goto ioctl_exit; /* server returned no data */ - else if (*plen > 0xFF00) { + else if (*plen > rsp_iov.iov_len || *plen > 0xFF00) { cifs_dbg(VFS, "srv returned invalid ioctl length: %d\n", *plen); *plen = 0; rc = -EIO; goto ioctl_exit; } - if (rsp_iov.iov_len < le32_to_cpu(rsp->OutputOffset) + *plen) { + if (rsp_iov.iov_len - *plen < le32_to_cpu(rsp->OutputOffset)) { cifs_dbg(VFS, "Malformed ioctl resp: len %d offset %d\n", *plen, le32_to_cpu(rsp->OutputOffset)); *plen = 0; |