linux-kernel - Re: [PATCH] net: fix memory leaks in flush

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <C9E5387E-6241-4CB3-B3F2-9CA575920569@lca.pw>
Date:   Sat, 2 May 2020 00:12:24 -0400
From:   Qian Cai <cai@....pw>
To:     Eric Dumazet <eric.dumazet@...il.com>
Cc:     davem@...emloft.net, kuba@...nel.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] net: fix memory leaks in flush_backlog() with RPS

> On May 1, 2020, at 11:32 PM, Eric Dumazet <eric.dumazet@...il.com> wrote:
> 
> kfree_skb() is supposed to call skb_dst_drop() (look in skb_release_head_state())
> 
> If you think about it, we would have hundreds of similar bugs if this was not the case.

Thanks for quick response. Funny thing is that once I applied this patch, the leaks went away. It could be the fuzzers do not always reproduce the leaks or it could be that call_rcu() in skb_dst_drop() takes a long time waiting for grace periods which may confuse kmemleak because skb has already gone.