netdev - Re: [PATCH] tools: bpftool: fix struct_ops command invalid pointer free

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

Message-ID: <20200410050333.qshidymodw3oyn6k@kafai-mbp>
Date:   Thu, 9 Apr 2020 22:03:33 -0700
From:   Martin KaFai Lau <kafai@...com>
To:     "Daniel T. Lee" <danieltimlee@...il.com>
CC:     Daniel Borkmann <daniel@...earbox.net>,
        Alexei Starovoitov <ast@...nel.org>, <netdev@...r.kernel.org>,
        <bpf@...r.kernel.org>
Subject: Re: [PATCH] tools: bpftool: fix struct_ops command invalid pointer
 free

On Fri, Apr 10, 2020 at 11:06:12AM +0900, Daniel T. Lee wrote:
> From commit 65c93628599d ("bpftool: Add struct_ops support"),
> a new type of command struct_ops has been added.
> 
> This command requires kernel CONFIG_DEBUG_INFO_BTF=y, and for retrieving
> btf info, get_btf_vmlinux() is used.
> 
> When running this command on kernel without BTF debug info, this will
> lead to 'btf_vmlinux' variable contains invalid(error) pointer. And by
> this, btf_free() causes a segfault when executing 'bpftool struct_ops'.
> 
> This commit adds pointer validation with IS_ERR not to free invalid
> pointer, and this will fix the segfault issue.
> 
> Signed-off-by: Daniel T. Lee <danieltimlee@...il.com>
Fixes: 65c93628599d ("bpftool: Add struct_ops support")
Acked-by: Martin KaFai Lau

Thanks for the fix!  Please add the Fixes tag in the future.