From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vasiliy Kulikov Subject: [PATCH v2] net: ax25: fix information leak to userland Date: Wed, 10 Nov 2010 21:12:36 +0300 Message-ID: <1289412757-11411-1-git-send-email-segooon@gmail.com> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:from:to:cc:subject:date :message-id:x-mailer; bh=HzmHEJ3/OExyew19gvJbYgqguIO0pMEskwbAU+ys5Tw=; b=pXtrknj7R8bVFgZjxsWSKKKzZS/WkLUlEOx571nLqLHDwXIkUe+t/XsFwguN8NWYnl +1l5ZDfhibYND7axgjMRdA9RMeAhgnkT3m8xgzCH+avEXG2+UZBfIc6F48HtZy+msWnC hUrXMQxpqRGM/VJTWO7Yl/tkDrCeTAxgiyTcQ= Sender: netdev-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kernel-janitors@vger.kernel.org Cc: Joerg Reuter , Ralf Baechle , "David S. Miller" , linux-hams@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Sometimes ax25_getname() doesn't initialize all members of fsa_digipeater field of fsa struct, also the struct has padding bytes between sax25_call and sax25_ndigis fields. This structure is then copied to userland. It leads to leaking of contents of kernel stack memory. Signed-off-by: Vasiliy Kulikov --- Compile tested. net/ax25/af_ax25.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index 26eaebf..bb86d29 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -1392,6 +1392,7 @@ static int ax25_getname(struct socket *sock, struct sockaddr *uaddr, ax25_cb *ax25; int err = 0; + memset(fsa, 0, sizeof(fsa)); lock_sock(sk); ax25 = ax25_sk(sk); @@ -1403,7 +1404,6 @@ static int ax25_getname(struct socket *sock, struct sockaddr *uaddr, fsa->fsa_ax25.sax25_family = AF_AX25; fsa->fsa_ax25.sax25_call = ax25->dest_addr; - fsa->fsa_ax25.sax25_ndigis = 0; if (ax25->digipeat != NULL) { ndigi = ax25->digipeat->ndigi; -- 1.7.0.4