netdev - Re: [PATCH bpf-next] bpf: fix too large copy from user in bpf_test

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: <169a1b10-4bb8-6ba1-4f5f-e74dd273107a@iogearbox.net>
Date:   Tue, 19 May 2020 19:22:08 +0200
From:   Daniel Borkmann <daniel@...earbox.net>
To:     Jesper Dangaard Brouer <brouer@...hat.com>
Cc:     netdev@...r.kernel.org, bpf@...r.kernel.org,
        Daniel Borkmann <borkmann@...earbox.net>,
        Alexei Starovoitov <alexei.starovoitov@...il.com>,
        "David S. Miller" <davem@...emloft.net>
Subject: Re: [PATCH bpf-next] bpf: fix too large copy from user in
 bpf_test_init

On 5/18/20 3:05 PM, Jesper Dangaard Brouer wrote:
> Commit bc56c919fce7 ("bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().")
> recently changed bpf_prog_test_run_xdp() to use larger frames for XDP in
> order to test tail growing frames (via bpf_xdp_adjust_tail) and to have
> memory backing frame better resemble drivers.
> 
> The commit contains a bug, as it tries to copy the max data size from
> userspace, instead of the size provided by userspace.  This cause XDP
> unit tests to fail sporadically with EFAULT, an unfortunate behavior.
> The fix is to only copy the size specified by userspace.
> 
> Fixes: bc56c919fce7 ("bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().")
> Signed-off-by: Jesper Dangaard Brouer <brouer@...hat.com>

Applied, thanks!