From: ZhangXiaoxu zhangxiaoxu5@huawei.com
commit 6a3eb3360667170988f8a6477f6686242061488a upstream.
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: eccb4422cf97 ("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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/cifs/smb2pdu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -3708,7 +3708,6 @@ SMB2_write(const unsigned int xid, struc
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) { @@ -3726,6 +3725,7 @@ SMB2_write(const unsigned int xid, struc io_parms->offset, *nbytes); }
+ cifs_small_buf_release(req); free_rsp_buf(resp_buftype, rsp); return rc; }