Re: [PATCH v2] ucounts: add missing data type changes

[ebiederm@xmission.com (Eric W. Biederman)]

Alexey Gladkov <legion@kernel.org> writes:

> On Wed, Jul 21, 2021 at 02:52:33PM +0200, Sven Schnelle wrote:
>> commit f9c82a4ea89c3 ("Increase size of ucounts to atomic_long_t")
>> changed the data type of ucounts/ucounts_max to long, but missed to
>> adjust a few other places. This is noticeable on big endian platforms
>> from user space because the /proc/sys/user/max_*_names files all
>> contain 0.
>> 
>> Fixes: f9c82a4ea89c ("Increase size of ucounts to atomic_long_t")
>> Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
>
> Acked-by: Alexey Gladkov <legion@kernel.org>
>
> Eric, what do you think ?

At a quick skim it looks good.  I was to swamped last week to pick it
up, but I plan on picking this up and getting it to Linus before
the next -rc release.

Eric

>> ---
>>  fs/notify/fanotify/fanotify_user.c | 10 ++++++----
>>  kernel/ucount.c                    | 16 ++++++++--------
>>  2 files changed, 14 insertions(+), 12 deletions(-)
>> 
>> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
>> index 64864fb40b40..6576657a1a25 100644
>> --- a/fs/notify/fanotify/fanotify_user.c
>> +++ b/fs/notify/fanotify/fanotify_user.c
>> @@ -58,18 +58,20 @@ struct ctl_table fanotify_table[] = {
>>  	{
>>  		.procname	= "max_user_groups",
>>  		.data	= &init_user_ns.ucount_max[UCOUNT_FANOTIFY_GROUPS],
>> -		.maxlen		= sizeof(int),
>> +		.maxlen		= sizeof(long),
>>  		.mode		= 0644,
>> -		.proc_handler	= proc_dointvec_minmax,
>> +		.proc_handler	= proc_doulongvec_minmax,
>>  		.extra1		= SYSCTL_ZERO,
>> +		.extra2		= SYSCTL_INT_MAX,
>>  	},
>>  	{
>>  		.procname	= "max_user_marks",
>>  		.data	= &init_user_ns.ucount_max[UCOUNT_FANOTIFY_MARKS],
>> -		.maxlen		= sizeof(int),
>> +		.maxlen		= sizeof(long),
>>  		.mode		= 0644,
>> -		.proc_handler	= proc_dointvec_minmax,
>> +		.proc_handler	= proc_doulongvec_minmax,
>>  		.extra1		= SYSCTL_ZERO,
>> +		.extra2		= SYSCTL_INT_MAX,
>>  	},
>>  	{
>>  		.procname	= "max_queued_events",
>> diff --git a/kernel/ucount.c b/kernel/ucount.c
>> index 87799e2379bd..f852591e395c 100644
>> --- a/kernel/ucount.c
>> +++ b/kernel/ucount.c
>> @@ -58,14 +58,14 @@ static struct ctl_table_root set_root = {
>>  	.permissions = set_permissions,
>>  };
>>  
>> -#define UCOUNT_ENTRY(name)				\
>> -	{						\
>> -		.procname	= name,			\
>> -		.maxlen		= sizeof(int),		\
>> -		.mode		= 0644,			\
>> -		.proc_handler	= proc_dointvec_minmax,	\
>> -		.extra1		= SYSCTL_ZERO,		\
>> -		.extra2		= SYSCTL_INT_MAX,	\
>> +#define UCOUNT_ENTRY(name)					\
>> +	{							\
>> +		.procname	= name,				\
>> +		.maxlen		= sizeof(long),			\
>> +		.mode		= 0644,				\
>> +		.proc_handler	= proc_doulongvec_minmax,	\
>> +		.extra1		= SYSCTL_ZERO,			\
>> +		.extra2		= SYSCTL_INT_MAX,		\
>>  	}
>>  static struct ctl_table user_table[] = {
>>  	UCOUNT_ENTRY("max_user_namespaces"),
>> -- 
>> 2.25.1
>>