netdev - Re: [PATCH bpf-next 01/15] selftests/bpf: Fix the u64_offset_to_skb

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: <w7xg34uqlrnbb3o3rspng6y563astp3hkfxjtz3xp32rqr4a42@xgpeu7qevatg>
Date: Tue, 26 Dec 2023 17:52:56 +0800
From: Shung-Hsi Yu <shung-hsi.yu@...e.com>
To: Maxim Mikityanskiy <maxtram95@...il.com>
Cc: Eduard Zingerman <eddyz87@...il.com>, 
	Alexei Starovoitov <ast@...nel.org>, Daniel Borkmann <daniel@...earbox.net>, 
	Andrii Nakryiko <andrii@...nel.org>, John Fastabend <john.fastabend@...il.com>, 
	Martin KaFai Lau <martin.lau@...ux.dev>, Song Liu <song@...nel.org>, 
	Yonghong Song <yonghong.song@...ux.dev>, KP Singh <kpsingh@...nel.org>, 
	Stanislav Fomichev <sdf@...gle.com>, Hao Luo <haoluo@...gle.com>, Jiri Olsa <jolsa@...nel.org>, 
	Mykola Lysenko <mykolal@...com>, Shuah Khan <shuah@...nel.org>, 
	"David S. Miller" <davem@...emloft.net>, Jakub Kicinski <kuba@...nel.org>, 
	Jesper Dangaard Brouer <hawk@...nel.org>, bpf@...r.kernel.org, linux-kselftest@...r.kernel.org, 
	netdev@...r.kernel.org, Maxim Mikityanskiy <maxim@...valent.com>
Subject: Re: [PATCH bpf-next 01/15] selftests/bpf: Fix the
 u64_offset_to_skb_data test

On Wed, Dec 20, 2023 at 11:39:59PM +0200, Maxim Mikityanskiy wrote:
> From: Maxim Mikityanskiy <maxim@...valent.com>
> 
> The u64_offset_to_skb_data test is supposed to make a 64-bit fill, but
> instead makes a 16-bit one. Fix the test according to its intention. The
> 16-bit fill is covered by u16_offset_to_skb_data.

Cover letter mentioned

  Patch 1 (Maxim): Fix for an existing test, it will matter later in the
  series.

However no subsequent patch touch upon u64_offset_to_skb_data(). Was the
followup missing from this series?

> Signed-off-by: Maxim Mikityanskiy <maxim@...valent.com>
> [...]
>  SEC("tc")
>  __description("Spill u32 const scalars.  Refill as u64.  Offset to skb->data")
> -__failure __msg("invalid access to packet")
> +__failure __msg("math between pkt pointer and register with unbounded min value is not allowed")
>  __naked void u64_offset_to_skb_data(void)
>  {
>  	asm volatile ("					\
> @@ -253,7 +253,7 @@ __naked void u64_offset_to_skb_data(void)
>  	w7 = 20;					\
>  	*(u32*)(r10 - 4) = r6;				\
>  	*(u32*)(r10 - 8) = r7;				\
> -	r4 = *(u16*)(r10 - 8);				\
> +	r4 = *(u64*)(r10 - 8);				\
>  	r0 = r2;					\
>  	/* r0 += r4 R0=pkt R2=pkt R3=pkt_end R4=umax=65535 */\
>  	r0 += r4;					\