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
| ||
|
Date: Wed, 23 Sep 2020 12:31:49 +0200 From: Greg KH <gregkh@...uxfoundation.org> To: Shuah Khan <skhan@...uxfoundation.org> Cc: johannes@...solutions.net, rafael@...nel.org, keescook@...omium.org, linux-kernel@...r.kernel.org Subject: Re: [RFC PATCH 04/11] drivers/base/devcoredump: convert devcd_count to counter_atomic On Tue, Sep 22, 2020 at 07:43:33PM -0600, Shuah Khan wrote: > counter_atomic is introduced to be used when a variable is used as > a simple counter and doesn't guard object lifetimes. This clearly > differentiates atomic_t usages that guard object lifetimes. > > counter_atomic variables will wrap around to 0 when it overflows and > should not be used to guard resource lifetimes, device usage and > open counts that control state changes, and pm states. > > devcd_count is used to track dev_coredumpm device count and used in > device name string. It doesn't guard object lifetimes, device usage > counts, device open counts, and pm states. There is very little chance > of this counter overflowing. Convert it to use counter_atomic. > > This conversion doesn't change the oveflow wrap around behavior. > > Signed-off-by: Shuah Khan <skhan@...uxfoundation.org> > --- > drivers/base/devcoredump.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/base/devcoredump.c b/drivers/base/devcoredump.c > index e42d0b514384..d719424d1e0b 100644 > --- a/drivers/base/devcoredump.c > +++ b/drivers/base/devcoredump.c > @@ -16,6 +16,7 @@ > #include <linux/slab.h> > #include <linux/fs.h> > #include <linux/workqueue.h> > +#include <linux/counters.h> > > static struct class devcd_class; > > @@ -255,7 +256,7 @@ void dev_coredumpm(struct device *dev, struct module *owner, > void *data, size_t datalen), > void (*free)(void *data)) > { > - static atomic_t devcd_count = ATOMIC_INIT(0); > + static struct counter_atomic devcd_count = COUNTER_ATOMIC_INIT(0); > struct devcd_entry *devcd; > struct device *existing; > > @@ -286,7 +287,7 @@ void dev_coredumpm(struct device *dev, struct module *owner, > device_initialize(&devcd->devcd_dev); > > dev_set_name(&devcd->devcd_dev, "devcd%d", > - atomic_inc_return(&devcd_count)); > + counter_atomic_inc_return(&devcd_count)); > devcd->devcd_dev.class = &devcd_class; > > if (device_add(&devcd->devcd_dev)) > -- > 2.25.1 > Reviewed-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Powered by blists - more mailing lists