linux-ext4 - Re: [RFC][PATCH v3 00/33] timers: Use timer

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: <20221104192232.GA2520396@roeck-us.net>
Date:   Fri, 4 Nov 2022 12:22:32 -0700
From:   Guenter Roeck <linux@...ck-us.net>
To:     Steven Rostedt <rostedt@...dmis.org>
Cc:     linux-kernel@...r.kernel.org,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Stephen Boyd <sboyd@...nel.org>,
        Anna-Maria Gleixner <anna-maria@...utronix.de>,
        Andrew Morton <akpm@...ux-foundation.org>, rcu@...r.kernel.org,
        linux-doc@...r.kernel.org, linux-s390@...r.kernel.org,
        linux-sh@...r.kernel.org, linux-edac@...r.kernel.org,
        cgroups@...r.kernel.org, linux-block@...r.kernel.org,
        linux-acpi@...r.kernel.org,
        linux-atm-general@...ts.sourceforge.net, netdev@...r.kernel.org,
        linux-pm@...r.kernel.org, drbd-dev@...ts.linbit.com,
        linux-bluetooth@...r.kernel.org,
        openipmi-developer@...ts.sourceforge.net,
        linux-media@...r.kernel.org, dri-devel@...ts.freedesktop.org,
        linaro-mm-sig@...ts.linaro.org, intel-gfx@...ts.freedesktop.org,
        linux-input@...r.kernel.org, linux-parisc@...r.kernel.org,
        linux-leds@...r.kernel.org, intel-wired-lan@...ts.osuosl.org,
        linux-usb@...r.kernel.org, linux-wireless@...r.kernel.org,
        linux-scsi@...r.kernel.org, linux-staging@...ts.linux.dev,
        linux-ext4@...r.kernel.org, linux-nilfs@...r.kernel.org,
        bridge@...ts.linux-foundation.org, netfilter-devel@...r.kernel.org,
        coreteam@...filter.org, lvs-devel@...r.kernel.org,
        linux-afs@...ts.infradead.org, linux-nfs@...r.kernel.org,
        tipc-discussion@...ts.sourceforge.net, alsa-devel@...a-project.org
Subject: Re: [RFC][PATCH v3 00/33] timers: Use timer_shutdown*() before
 freeing timers

On Fri, Nov 04, 2022 at 01:40:53AM -0400, Steven Rostedt wrote:
> 
> Back in April, I posted an RFC patch set to help mitigate a common issue
> where a timer gets armed just before it is freed, and when the timer
> goes off, it crashes in the timer code without any evidence of who the
> culprit was. I got side tracked and never finished up on that patch set.
> Since this type of crash is still our #1 crash we are seeing in the field,
> it has become a priority again to finish it.
> 
> This is v3 of that patch set. Thomas Gleixner posted an untested version
> that makes timer->function NULL as the flag that it is shutdown. I took that
> code, tested it (fixed it up), added more comments, and changed the
> name to timer_shutdown_sync(). I also converted it to use WARN_ON_ONCE()
> instead of just WARN_ON() as Linus asked for.
> 

Unfortunately the renaming caused some symbol conflicts.

Global definition: timer_shutdown

  File             Line
0 time.c            93 static inline void timer_shutdown(struct clock_event_device *evt)
1 arm_arch_timer.c 690 static __always_inline int timer_shutdown(const int access,
2 timer-fttmr010.c 105 int (*timer_shutdown)(struct clock_event_device *evt);
3 timer-sp804.c    158 static inline void timer_shutdown(struct clock_event_device *evt)
4 timer.h          239 static inline int timer_shutdown(struct timer_list *timer)

Guenter