linux-kernel - Re: [PATCH v2] MIPS: KASLR: Avoid endless loop in sync_icache when synci

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]

Date:   Mon, 7 Dec 2020 11:32:51 +0100
From:   Thomas Bogendoerfer <tsbogend@...ha.franken.de>
To:     Jinyang He <hejinyang@...ngson.cn>
Cc:     linux-mips@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2] MIPS: KASLR: Avoid endless loop in sync_icache when
 synci_step is zero

On Fri, Dec 04, 2020 at 09:11:46AM +0800, Jinyang He wrote:
> Avoid endless loop if synci_step was zero read by rdhwr instruction.
> 
> Most platforms do not need to do synci instruction operations when
> synci_step is 0. But for example, the synci implementation on Loongson64
> platform has some changes. On the one hand, it ensures that the memory
> access instructions have been completed. On the other hand, it guarantees
> that all prefetch instructions need to be fetched again. And its address
> information is useless. Thus, only one synci operation is required when
> synci_step is 0 on Loongson64 platform. I guess that some other platforms
> have similar implementations on synci, so add judgment conditions in
> `while` to ensure that at least all platforms perform synci operations
> once. For those platforms that do not need synci, they just do one more
> operation similar to nop.
> 
> Signed-off-by: Jinyang He <hejinyang@...ngson.cn>
> ---
>  arch/mips/kernel/relocate.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

applied to mips-next.

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]