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* [PATCH] ucounts: add missing data type changes
@ 2021-07-21 11:58 Sven Schnelle
  2021-07-21 12:27 ` Alexey Gladkov
  0 siblings, 1 reply; 4+ messages in thread
From: Sven Schnelle @ 2021-07-21 11:58 UTC (permalink / raw)
  To: Eric W. Biederman; +Cc: Alexey Gladkov, linux-kernel, Sven Schnelle

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>
---
 fs/notify/fanotify/fanotify_user.c | 11 +++++++----
 kernel/ucount.c                    | 18 ++++++++++--------
 kernel/user_namespace.c            |  2 +-
 3 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 64864fb40b40..995379ddce86 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -54,22 +54,25 @@ static int fanotify_max_queued_events __read_mostly;
 
 #include <linux/sysctl.h>
 
+static unsigned long long_max = LONG_MAX;
 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		= &long_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		= &long_max,
 	},
 	{
 		.procname	= "max_queued_events",
diff --git a/kernel/ucount.c b/kernel/ucount.c
index 87799e2379bd..681ea1b1a06f 100644
--- a/kernel/ucount.c
+++ b/kernel/ucount.c
@@ -58,14 +58,16 @@ 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,	\
+static unsigned long long_max = LONG_MAX;
+
+#define UCOUNT_ENTRY(name)					\
+	{							\
+		.procname	= name,				\
+		.maxlen		= sizeof(long),			\
+		.mode		= 0644,				\
+		.proc_handler	= proc_doulongvec_minmax,	\
+		.extra1		= SYSCTL_ZERO,			\
+		.extra2		= &long_max,			\
 	}
 static struct ctl_table user_table[] = {
 	UCOUNT_ENTRY("max_user_namespaces"),
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index ef82d401dde8..d8ad4c261253 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -120,7 +120,7 @@ int create_user_ns(struct cred *new)
 	ns->group = group;
 	INIT_WORK(&ns->work, free_user_ns);
 	for (i = 0; i < MAX_PER_NAMESPACE_UCOUNTS; i++) {
-		ns->ucount_max[i] = INT_MAX;
+		ns->ucount_max[i] = LONG_MAX;
 	}
 	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC));
 	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_MSGQUEUE, rlimit(RLIMIT_MSGQUEUE));
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH] ucounts: add missing data type changes
  2021-07-21 11:58 [PATCH] ucounts: add missing data type changes Sven Schnelle
@ 2021-07-21 12:27 ` Alexey Gladkov
  2021-07-21 12:32   ` Sven Schnelle
  0 siblings, 1 reply; 4+ messages in thread
From: Alexey Gladkov @ 2021-07-21 12:27 UTC (permalink / raw)
  To: Sven Schnelle; +Cc: Eric W. Biederman, linux-kernel

On Wed, Jul 21, 2021 at 01:58:00PM +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.

I didn't increase them because I didn't want to increase the maximum
number of namespaces.

Your patch not only fixes the described problem, but also increases the
maximum number of namespaces.

> Fixes: f9c82a4ea89c ("Increase size of ucounts to atomic_long_t")
> Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
> ---
>  fs/notify/fanotify/fanotify_user.c | 11 +++++++----
>  kernel/ucount.c                    | 18 ++++++++++--------
>  kernel/user_namespace.c            |  2 +-
>  3 files changed, 18 insertions(+), 13 deletions(-)
> 
> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> index 64864fb40b40..995379ddce86 100644
> --- a/fs/notify/fanotify/fanotify_user.c
> +++ b/fs/notify/fanotify/fanotify_user.c
> @@ -54,22 +54,25 @@ static int fanotify_max_queued_events __read_mostly;
>  
>  #include <linux/sysctl.h>
>  
> +static unsigned long long_max = LONG_MAX;

I think this should be INT_MAX.

>  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		= &long_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		= &long_max,
>  	},
>  	{
>  		.procname	= "max_queued_events",
> diff --git a/kernel/ucount.c b/kernel/ucount.c
> index 87799e2379bd..681ea1b1a06f 100644
> --- a/kernel/ucount.c
> +++ b/kernel/ucount.c
> @@ -58,14 +58,16 @@ 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,	\
> +static unsigned long long_max = LONG_MAX;
> +
> +#define UCOUNT_ENTRY(name)					\
> +	{							\
> +		.procname	= name,				\
> +		.maxlen		= sizeof(long),			\
> +		.mode		= 0644,				\
> +		.proc_handler	= proc_doulongvec_minmax,	\
> +		.extra1		= SYSCTL_ZERO,			\
> +		.extra2		= &long_max,			\
>  	}
>  static struct ctl_table user_table[] = {
>  	UCOUNT_ENTRY("max_user_namespaces"),
> diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
> index ef82d401dde8..d8ad4c261253 100644
> --- a/kernel/user_namespace.c
> +++ b/kernel/user_namespace.c
> @@ -120,7 +120,7 @@ int create_user_ns(struct cred *new)
>  	ns->group = group;
>  	INIT_WORK(&ns->work, free_user_ns);
>  	for (i = 0; i < MAX_PER_NAMESPACE_UCOUNTS; i++) {
> -		ns->ucount_max[i] = INT_MAX;
> +		ns->ucount_max[i] = LONG_MAX;
>  	}
>  	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC));
>  	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_MSGQUEUE, rlimit(RLIMIT_MSGQUEUE));
> -- 
> 2.25.1
> 

-- 
Rgrds, legion


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] ucounts: add missing data type changes
  2021-07-21 12:27 ` Alexey Gladkov
@ 2021-07-21 12:32   ` Sven Schnelle
  2021-07-21 12:43     ` Alexey Gladkov
  0 siblings, 1 reply; 4+ messages in thread
From: Sven Schnelle @ 2021-07-21 12:32 UTC (permalink / raw)
  To: Alexey Gladkov; +Cc: Eric W. Biederman, linux-kernel

Alexey Gladkov <legion@kernel.org> writes:

> On Wed, Jul 21, 2021 at 01:58:00PM +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.
>
> I didn't increase them because I didn't want to increase the maximum
> number of namespaces.
>
> Your patch not only fixes the described problem, but also increases the
> maximum number of namespaces.
>
>> Fixes: f9c82a4ea89c ("Increase size of ucounts to atomic_long_t")
>> Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
>> ---
>>  fs/notify/fanotify/fanotify_user.c | 11 +++++++----
>>  kernel/ucount.c                    | 18 ++++++++++--------
>>  kernel/user_namespace.c            |  2 +-
>>  3 files changed, 18 insertions(+), 13 deletions(-)
>> 
>> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
>> index 64864fb40b40..995379ddce86 100644
>> --- a/fs/notify/fanotify/fanotify_user.c
>> +++ b/fs/notify/fanotify/fanotify_user.c
>> @@ -54,22 +54,25 @@ static int fanotify_max_queued_events __read_mostly;
>>  
>>  #include <linux/sysctl.h>
>>  
>> +static unsigned long long_max = LONG_MAX;
>
> I think this should be INT_MAX.

Thanks. I'll change the code to use SYSCTL_INT_MAX instead and send a
v2.

>>  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		= &long_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		= &long_max,
>>  	},
>>  	{
>>  		.procname	= "max_queued_events",
>> diff --git a/kernel/ucount.c b/kernel/ucount.c
>> index 87799e2379bd..681ea1b1a06f 100644
>> --- a/kernel/ucount.c
>> +++ b/kernel/ucount.c
>> @@ -58,14 +58,16 @@ 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,	\
>> +static unsigned long long_max = LONG_MAX;
>> +
>> +#define UCOUNT_ENTRY(name)					\
>> +	{							\
>> +		.procname	= name,				\
>> +		.maxlen		= sizeof(long),			\
>> +		.mode		= 0644,				\
>> +		.proc_handler	= proc_doulongvec_minmax,	\
>> +		.extra1		= SYSCTL_ZERO,			\
>> +		.extra2		= &long_max,			\
>>  	}
>>  static struct ctl_table user_table[] = {
>>  	UCOUNT_ENTRY("max_user_namespaces"),
>> diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
>> index ef82d401dde8..d8ad4c261253 100644
>> --- a/kernel/user_namespace.c
>> +++ b/kernel/user_namespace.c
>> @@ -120,7 +120,7 @@ int create_user_ns(struct cred *new)
>>  	ns->group = group;
>>  	INIT_WORK(&ns->work, free_user_ns);
>>  	for (i = 0; i < MAX_PER_NAMESPACE_UCOUNTS; i++) {
>> -		ns->ucount_max[i] = INT_MAX;
>> +		ns->ucount_max[i] = LONG_MAX;

Guess this should also stay at INT_MAX?

>>  	}
>>  	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC));
>>  	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_MSGQUEUE, rlimit(RLIMIT_MSGQUEUE));
>> -- 
>> 2.25.1
>> 

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] ucounts: add missing data type changes
  2021-07-21 12:32   ` Sven Schnelle
@ 2021-07-21 12:43     ` Alexey Gladkov
  0 siblings, 0 replies; 4+ messages in thread
From: Alexey Gladkov @ 2021-07-21 12:43 UTC (permalink / raw)
  To: Sven Schnelle; +Cc: Eric W. Biederman, linux-kernel

On Wed, Jul 21, 2021 at 02:32:38PM +0200, Sven Schnelle wrote:
> Alexey Gladkov <legion@kernel.org> writes:
> 
> > On Wed, Jul 21, 2021 at 01:58:00PM +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.
> >
> > I didn't increase them because I didn't want to increase the maximum
> > number of namespaces.
> >
> > Your patch not only fixes the described problem, but also increases the
> > maximum number of namespaces.
> >
> >> Fixes: f9c82a4ea89c ("Increase size of ucounts to atomic_long_t")
> >> Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
> >> ---
> >>  fs/notify/fanotify/fanotify_user.c | 11 +++++++----
> >>  kernel/ucount.c                    | 18 ++++++++++--------
> >>  kernel/user_namespace.c            |  2 +-
> >>  3 files changed, 18 insertions(+), 13 deletions(-)
> >> 
> >> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> >> index 64864fb40b40..995379ddce86 100644
> >> --- a/fs/notify/fanotify/fanotify_user.c
> >> +++ b/fs/notify/fanotify/fanotify_user.c
> >> @@ -54,22 +54,25 @@ static int fanotify_max_queued_events __read_mostly;
> >>  
> >>  #include <linux/sysctl.h>
> >>  
> >> +static unsigned long long_max = LONG_MAX;
> >
> > I think this should be INT_MAX.
> 
> Thanks. I'll change the code to use SYSCTL_INT_MAX instead and send a
> v2.
> 
> >>  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		= &long_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		= &long_max,
> >>  	},
> >>  	{
> >>  		.procname	= "max_queued_events",
> >> diff --git a/kernel/ucount.c b/kernel/ucount.c
> >> index 87799e2379bd..681ea1b1a06f 100644
> >> --- a/kernel/ucount.c
> >> +++ b/kernel/ucount.c
> >> @@ -58,14 +58,16 @@ 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,	\
> >> +static unsigned long long_max = LONG_MAX;
> >> +
> >> +#define UCOUNT_ENTRY(name)					\
> >> +	{							\
> >> +		.procname	= name,				\
> >> +		.maxlen		= sizeof(long),			\
> >> +		.mode		= 0644,				\
> >> +		.proc_handler	= proc_doulongvec_minmax,	\
> >> +		.extra1		= SYSCTL_ZERO,			\
> >> +		.extra2		= &long_max,			\
> >>  	}
> >>  static struct ctl_table user_table[] = {
> >>  	UCOUNT_ENTRY("max_user_namespaces"),
> >> diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
> >> index ef82d401dde8..d8ad4c261253 100644
> >> --- a/kernel/user_namespace.c
> >> +++ b/kernel/user_namespace.c
> >> @@ -120,7 +120,7 @@ int create_user_ns(struct cred *new)
> >>  	ns->group = group;
> >>  	INIT_WORK(&ns->work, free_user_ns);
> >>  	for (i = 0; i < MAX_PER_NAMESPACE_UCOUNTS; i++) {
> >> -		ns->ucount_max[i] = INT_MAX;
> >> +		ns->ucount_max[i] = LONG_MAX;
> 
> Guess this should also stay at INT_MAX?

Yes.

> >>  	}
> >>  	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC));
> >>  	set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_MSGQUEUE, rlimit(RLIMIT_MSGQUEUE));
> >> -- 
> >> 2.25.1
> >> 
> 

-- 
Rgrds, legion


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2021-07-21 12:43 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-07-21 11:58 [PATCH] ucounts: add missing data type changes Sven Schnelle
2021-07-21 12:27 ` Alexey Gladkov
2021-07-21 12:32   ` Sven Schnelle
2021-07-21 12:43     ` Alexey Gladkov

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