BPF List
 help / color / mirror / Atom feed
From: xiakaixu1987@gmail.com
To: ast@kernel.org, daniel@iogearbox.net, kafai@fb.com,
	songliubraving@fb.com, yhs@fb.com, andrii@kernel.org,
	john.fastabend@gmail.com, kpsingh@chromium.org
Cc: netdev@vger.kernel.org, bpf@vger.kernel.org,
	linux-kernel@vger.kernel.org, Kaixu Xia <kaixuxia@tencent.com>
Subject: [PATCH] bpf: Check the return value of dev_get_by_index_rcu()
Date: Thu, 19 Nov 2020 15:04:28 +0800	[thread overview]
Message-ID: <1605769468-2078-1-git-send-email-kaixuxia@tencent.com> (raw)

From: Kaixu Xia <kaixuxia@tencent.com>

The return value of dev_get_by_index_rcu() can be NULL, so here it
is need to check the return value and return error code if it is NULL.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
---
 net/core/filter.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/core/filter.c b/net/core/filter.c
index 2ca5eecebacf..1263fe07170a 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5573,6 +5573,8 @@ BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
 		struct net_device *dev;
 
 		dev = dev_get_by_index_rcu(net, params->ifindex);
+		if (unlikely(!dev))
+			return -EINVAL;
 		if (!is_skb_forwardable(dev, skb))
 			rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
 	}
-- 
2.20.0


             reply	other threads:[~2020-11-19  7:05 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-19  7:04 xiakaixu1987 [this message]
2020-11-20 15:13 ` [PATCH] bpf: Check the return value of dev_get_by_index_rcu() Daniel Borkmann
2020-11-20 15:19   ` David Ahern
2020-11-20 16:01     ` Daniel Borkmann

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=1605769468-2078-1-git-send-email-kaixuxia@tencent.com \
    --to=xiakaixu1987@gmail.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=john.fastabend@gmail.com \
    --cc=kafai@fb.com \
    --cc=kaixuxia@tencent.com \
    --cc=kpsingh@chromium.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=songliubraving@fb.com \
    --cc=yhs@fb.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox