cifs: Fix use-after-free in SMB2_write

There is a KASAN use-after-free:
BUG: KASAN: use-after-free in SMB2_write+0x1342/0x1580
Read of size 8 at addr ffff8880b6a8e450 by task ln/4196

Should not release the 'req' because it will use in the trace.

Fixes: eccb4422cf ("smb3: Add ftrace tracepoints for improved SMB3 debugging")

Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org> 4.18+
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
This commit is contained in:
ZhangXiaoxu 2019-04-06 15:47:38 +08:00 committed by Steve French
parent 618d919cae
commit 6a3eb33606

View file

@ -3769,7 +3769,6 @@ SMB2_write(const unsigned int xid, struct cifs_io_parms *io_parms,
rc = cifs_send_recv(xid, io_parms->tcon->ses, &rqst,
&resp_buftype, flags, &rsp_iov);
cifs_small_buf_release(req);
rsp = (struct smb2_write_rsp *)rsp_iov.iov_base;
if (rc) {
@ -3787,6 +3786,7 @@ SMB2_write(const unsigned int xid, struct cifs_io_parms *io_parms,
io_parms->offset, *nbytes);
}
cifs_small_buf_release(req);
free_rsp_buf(resp_buftype, rsp);
return rc;
}