From: Simon Horman <simon.horman@corigine.com>
To: Ziyang Xuan <william.xuanziyang@huawei.com>
Cc: mani@kernel.org, davem@davemloft.net, edumazet@google.com,
kuba@kernel.org, pabeni@redhat.com,
linux-arm-msm@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH net v2] net: qrtr: Fix an uninit variable access bug in qrtr_tx_resume()
Date: Mon, 10 Apr 2023 10:20:38 +0200 [thread overview]
Message-ID: <ZDPG1oqiZSFaSif2@corigine.com> (raw)
In-Reply-To: <20230410012352.3997823-1-william.xuanziyang@huawei.com>
On Mon, Apr 10, 2023 at 09:23:52AM +0800, Ziyang Xuan wrote:
> Syzbot reported a bug as following:
>
> =====================================================
> BUG: KMSAN: uninit-value in qrtr_tx_resume+0x185/0x1f0 net/qrtr/af_qrtr.c:230
> qrtr_tx_resume+0x185/0x1f0 net/qrtr/af_qrtr.c:230
> qrtr_endpoint_post+0xf85/0x11b0 net/qrtr/af_qrtr.c:519
> qrtr_tun_write_iter+0x270/0x400 net/qrtr/tun.c:108
> call_write_iter include/linux/fs.h:2189 [inline]
> aio_write+0x63a/0x950 fs/aio.c:1600
> io_submit_one+0x1d1c/0x3bf0 fs/aio.c:2019
> __do_sys_io_submit fs/aio.c:2078 [inline]
> __se_sys_io_submit+0x293/0x770 fs/aio.c:2048
> __x64_sys_io_submit+0x92/0xd0 fs/aio.c:2048
> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
> entry_SYSCALL_64_after_hwframe+0x63/0xcd
>
> Uninit was created at:
> slab_post_alloc_hook mm/slab.h:766 [inline]
> slab_alloc_node mm/slub.c:3452 [inline]
> __kmem_cache_alloc_node+0x71f/0xce0 mm/slub.c:3491
> __do_kmalloc_node mm/slab_common.c:967 [inline]
> __kmalloc_node_track_caller+0x114/0x3b0 mm/slab_common.c:988
> kmalloc_reserve net/core/skbuff.c:492 [inline]
> __alloc_skb+0x3af/0x8f0 net/core/skbuff.c:565
> __netdev_alloc_skb+0x120/0x7d0 net/core/skbuff.c:630
> qrtr_endpoint_post+0xbd/0x11b0 net/qrtr/af_qrtr.c:446
> qrtr_tun_write_iter+0x270/0x400 net/qrtr/tun.c:108
> call_write_iter include/linux/fs.h:2189 [inline]
> aio_write+0x63a/0x950 fs/aio.c:1600
> io_submit_one+0x1d1c/0x3bf0 fs/aio.c:2019
> __do_sys_io_submit fs/aio.c:2078 [inline]
> __se_sys_io_submit+0x293/0x770 fs/aio.c:2048
> __x64_sys_io_submit+0x92/0xd0 fs/aio.c:2048
> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
> entry_SYSCALL_64_after_hwframe+0x63/0xcd
>
> It is because that skb->len requires at least sizeof(struct qrtr_ctrl_pkt)
> in qrtr_tx_resume(). And skb->len equals to size in qrtr_endpoint_post().
> But size is less than sizeof(struct qrtr_ctrl_pkt) when qrtr_cb->type
> equals to QRTR_TYPE_RESUME_TX in qrtr_endpoint_post() under the syzbot
> scenario. This triggers the uninit variable access bug.
>
> Add size check when qrtr_cb->type equals to QRTR_TYPE_RESUME_TX in
> qrtr_endpoint_post() to fix the bug.
>
> Fixes: 5fdeb0d372ab ("net: qrtr: Implement outgoing flow control")
> Reported-by: syzbot+4436c9630a45820fda76@syzkaller.appspotmail.com
> Link: https://syzkaller.appspot.com/bug?id=c14607f0963d27d5a3d5f4c8639b500909e43540
> Suggested-by: Manivannan Sadhasivam <mani@kernel.org>
> Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
next prev parent reply other threads:[~2023-04-10 8:20 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-10 1:23 [PATCH net v2] net: qrtr: Fix an uninit variable access bug in qrtr_tx_resume() Ziyang Xuan
2023-04-10 8:20 ` Simon Horman [this message]
2023-04-13 7:50 ` patchwork-bot+netdevbpf
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=ZDPG1oqiZSFaSif2@corigine.com \
--to=simon.horman@corigine.com \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=kuba@kernel.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=mani@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=william.xuanziyang@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.