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
| ||
|
Message-ID: <CAJKOXPeNZDXFSC2NDMj4zERYEv58i+nqoA8D+GL827Sbmxxafg@mail.gmail.com> Date: Thu, 14 Dec 2017 11:11:07 +0100 From: Krzysztof Kozlowski <krzk@...nel.org> To: Jia-Ju Bai <baijiaju1990@....com> Cc: sbkim73@...sung.com, Sylwester Nawrocki <s.nawrocki@...sung.com>, lgirdwood@...il.com, broonie@...nel.org, perex@...ex.cz, tiwai@...e.com, alsa-devel@...a-project.org, Linux Kernel Mailing List <linux-kernel@...r.kernel.org> Subject: Re: [BUG] sound/soc/samsung: a possible sleep-in-atomic bugs in s3c_pcm_hw_params On Tue, Dec 12, 2017 at 2:24 AM, Jia-Ju Bai <baijiaju1990@....com> wrote: > According to sound/soc/samsung/pcm.c, the kernel module may sleep under a > spinlock. > The function call path is: > s3c_pcm_hw_params (acquire the spinlock) > clk_get_rate > clk_core_get_rate > clk_prepare_lock > mutex_lock --> may sleep > > I do not find a good way to fix it, so I only report. > This possible bug is found by my static analysis tool (DSAC) and my code > review. Thanks for the report. Your finding looks correct, the code might sleep under spinlock. I do not see easy solution. Maybe the readl(regs + S3C_PCM_CLKCTL) and clk_get_rate() could be moved before spinlock. The second path modifying it - s3c_pcm_set_sysclk() - is not protected by it. The spinlock is not effective around it. Best regards, Krzysztof
Powered by blists - more mailing lists