From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 03A6CD2FC for ; Sun, 1 Oct 2023 17:47:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D35CC433C7; Sun, 1 Oct 2023 17:47:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696182463; bh=VNL+SouT3OsiGYd/abICcjrcDWYcEzjJSaFaLuydeQU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DBIdW5FnY8o6rsafG//hdt53G2vfWcCyiKmrjFDjZJJBQJ+onheMcG87+ZQvZOlds fTmq8k0UWAv51F71S0DcAR9rQFbprtfpDnygni49xK2PoTPWgU/fHZQW7cUEgS+ItE y9FK4yjCaIE0N0AkaFHkvluc3wZIWqQbXXAti1ciFAxMrTbaTYpfbkTEDIXtZ7KiYV ljY9Ms+3pzF2NtCMHOyrazIEVaIqmORct+TJbOZYnMQdB9oxKqCs2TAMj8BZNowqmp LFifGnMBVl7DPFcchkFUxWeCkYoB8WZeM1QttOFqYA1J3NcM5K7uSaAoL1HpDKYwuE WWccuqQv4/c9Q== Date: Sun, 1 Oct 2023 19:47:39 +0200 From: Simon Horman To: Shigeru Yoshida Cc: jmaloy@redhat.com, ying.xue@windriver.com, netdev@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-kernel@vger.kernel.org, syzbot+9425c47dccbcb4c17d51@syzkaller.appspotmail.com Subject: Re: [PATCH] tipc: Fix uninit-value access in __tipc_nl_bearer_enable() Message-ID: <20231001174739.GS92317@kernel.org> References: <20230926125120.152133-1-syoshida@redhat.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230926125120.152133-1-syoshida@redhat.com> On Tue, Sep 26, 2023 at 09:51:20PM +0900, Shigeru Yoshida wrote: > syzbot reported the following uninit-value access issue: > > ===================================================== > BUG: KMSAN: uninit-value in strscpy+0xc4/0x160 > strscpy+0xc4/0x160 > bearer_name_validate net/tipc/bearer.c:147 [inline] > tipc_enable_bearer net/tipc/bearer.c:259 [inline] > __tipc_nl_bearer_enable+0x634/0x2220 net/tipc/bearer.c:1043 > tipc_nl_bearer_enable+0x3c/0x70 net/tipc/bearer.c:1052 > genl_family_rcv_msg_doit net/netlink/genetlink.c:971 [inline] > genl_family_rcv_msg net/netlink/genetlink.c:1051 [inline] > genl_rcv_msg+0x11ec/0x1290 net/netlink/genetlink.c:1066 > netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2545 > genl_rcv+0x40/0x60 net/netlink/genetlink.c:1075 > netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] > netlink_unicast+0xf47/0x1250 net/netlink/af_netlink.c:1368 > netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910 > sock_sendmsg_nosec net/socket.c:730 [inline] > sock_sendmsg net/socket.c:753 [inline] > ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2540 > ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2594 > __sys_sendmsg net/socket.c:2623 [inline] > __do_sys_sendmsg net/socket.c:2632 [inline] > __se_sys_sendmsg net/socket.c:2630 [inline] > __x64_sys_sendmsg+0x307/0x490 net/socket.c:2630 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x63/0xcd > > Uninit was created at: > slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767 > slab_alloc_node mm/slub.c:3478 [inline] > kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3523 > kmalloc_reserve+0x148/0x470 net/core/skbuff.c:559 > __alloc_skb+0x318/0x740 net/core/skbuff.c:644 > alloc_skb include/linux/skbuff.h:1286 [inline] > netlink_alloc_large_skb net/netlink/af_netlink.c:1214 [inline] > netlink_sendmsg+0xb34/0x13d0 net/netlink/af_netlink.c:1885 > sock_sendmsg_nosec net/socket.c:730 [inline] > sock_sendmsg net/socket.c:753 [inline] > ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2540 > ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2594 > __sys_sendmsg net/socket.c:2623 [inline] > __do_sys_sendmsg net/socket.c:2632 [inline] > __se_sys_sendmsg net/socket.c:2630 [inline] > __x64_sys_sendmsg+0x307/0x490 net/socket.c:2630 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x63/0xcd > > Bearer names must be null-terminated strings. If a bearer name which is not > null-terminated is passed through netlink, strcpy() and similar functions > can cause buffer overrun. This causes the above issue. > > This patch fixes this issue by returning -EINVAL if a non-null-terminated > bearer name is passed. > > Fixes: 0655f6a8635b ("tipc: add bearer disable/enable to new netlink api") > Reported-and-tested-by: syzbot+9425c47dccbcb4c17d51@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=9425c47dccbcb4c17d51 > Signed-off-by: Shigeru Yoshida Reviewed-by: Simon Horman