linux-kernel - Re: [PATCH-next] x86/kernel: Fix unchecked return value

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: <YKAw3Yl8c6nU1zng@zn.tnic>
Date:   Sat, 15 May 2021 22:36:45 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Khaled ROMDHANI <khaledromdhani216@...il.com>
Cc:     peterz@...radead.org, jpoimboe@...hat.com, jbaron@...mai.com,
        rostedt@...dmis.org, ardb@...nel.org, tglx@...utronix.de,
        mingo@...hat.com, x86@...nel.org, hpa@...or.com,
        linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: Re: [PATCH-next] x86/kernel: Fix unchecked return value

On Sat, May 15, 2021 at 09:22:12PM +0100, Khaled ROMDHANI wrote:
> From the coverity scan analysis, the return value from
> insn_decode_kernel is not checked. It is a macro constructed
> from the insn_decode function which may fail and return
> negative integer. Fix this by explicitly checking the
> return value.
> 
> Addresses-Coverity: ("Unchecked return value")
> Signed-off-by: Khaled ROMDHANI <khaledromdhani216@...il.com>
> ---
>  arch/x86/kernel/jump_label.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
> index a762dc1c615e..bf0ea003b6e7 100644
> --- a/arch/x86/kernel/jump_label.c
> +++ b/arch/x86/kernel/jump_label.c
> @@ -23,7 +23,7 @@ int arch_jump_entry_size(struct jump_entry *entry)
>  {
>  	struct insn insn = {};
>  
> -	insn_decode_kernel(&insn, (void *)jump_entry_code(entry));
> +	WARN_ON(insn_decode_kernel(&insn, (void *)jump_entry_code(entry)));

I don't think coverity is smart enough to notice...

>  	BUG_ON(insn.length != 2 && insn.length != 5);
	^^^^^^^^^^^^^

... this line.


-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette