linux-kernel - Re: [PATCH v2] ARM: DMA: Fix kzalloc flags in __dma

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]

Date:	Fri, 18 Mar 2016 11:38:29 +0100
From:	Rabin Vincent <rabin@....in>
To:	Alexandre Courbot <acourbot@...dia.com>
Cc:	Russell King <linux@....linux.org.uk>,
	Marek Szyprowski <m.szyprowski@...sung.com>,
	Thierry Reding <thierry.reding@...il.com>,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	gnurou@...il.com
Subject: Re: [PATCH v2] ARM: DMA: Fix kzalloc flags in __dma_alloc

On Fri, Mar 18, 2016 at 06:28:49PM +0900, Alexandre Courbot wrote:
> Commit 19e6e5e5392b ("ARM: 8547/1: dma-mapping: store buffer
> information") allocates a structure meant for internal buffer management
> with the GFP flags of the buffer itself. This can trigger the following
> safeguard in the slab/slub allocator:
> 
> 	if (unlikely(flags & GFP_SLAB_BUG_MASK)) {
> 		pr_emerg("gfp: %u\n", flags & GFP_SLAB_BUG_MASK);
> 		BUG();
> 	}
> 
> Fix this by filtering the flags that make the slab allocator unhappy.
> 
> Signed-off-by: Alexandre Courbot <acourbot@...dia.com>
> Cc: Rabin Vincent <rabin@....in>
> ---
> Changes since v1:
> - Filter flags that may cause problem instead of forcing GFP_KERNEL
>   (and risk sleeping in atomic context), as suggested by Rabin.

Acked-by: Rabin Vincent <rabin@....in>

Thanks.