From mboxrd@z Thu Jan 1 00:00:00 1970 From: shuwang@redhat.com Subject: [PATCH] SMB: fix memory leak in smb3_validate_negotiate Date: Fri, 20 Oct 2017 18:20:33 +0800 Message-ID: <20171020102033.22936-1-shuwang@redhat.com> Cc: linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, chuhu@redhat.com, yizhan@redhat.com, Shu Wang To: sfrench@samba.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-cifs.vger.kernel.org From: Shu Wang Found the issue by kmemleak. The pointer pneg_rsp stores the pointer kmalloced from SMB2_ioctl, and should be release before function return. unreferenced object 0xffff88018c2b1900 (size 32): backtrace: kmemleak_alloc+0x4a/0xa0 __kmalloc+0xec/0x220 SMB2_ioctl+0x27a/0x3c0 [cifs] smb3_validate_negotiate+0x135/0x370 [cifs] SMB2_tcon+0x308/0xae0 [cifs] cifs_put_tcp_session+0x4a5/0x900 [cifs] cifs_mount+0x6f4/0x15f0 [cifs] Signed-off-by: Shu Wang --- fs/cifs/smb2pdu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 6f0e6343c15e..4785ed8e1589 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -727,8 +727,10 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon) rsplen); /* relax check since Mac returns max bufsize allowed on ioctl */ - if (rsplen > CIFSMaxBufSize) + if (rsplen > CIFSMaxBufSize) { + kfree(pneg_rsp); return -EIO; + } } /* check validate negotiate info response matches what we got earlier */ @@ -747,10 +749,12 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon) /* validate negotiate successful */ cifs_dbg(FYI, "validate negotiate info successful\n"); + kfree(pneg_rsp); return 0; vneg_out: cifs_dbg(VFS, "protocol revalidation - security settings mismatch\n"); + kfree(pneg_rsp); return -EIO; } -- 2.13.5