2021-07-21 14:00:52

by Sven Schnelle

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

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 <[email protected]>
---
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

2021-07-26 19:07:54

by Alexey Gladkov

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

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 <[email protected]>

Acked-by: Alexey Gladkov <[email protected]>

Eric, what do you think ?

> ---
> 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
>

--
Rgrds, legion

2021-07-26 19:32:46

by Eric W. Biederman

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

Alexey Gladkov <[email protected]> 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 <[email protected]>
>
> Acked-by: Alexey Gladkov <[email protected]>
>
> 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
>>

2021-07-28 17:21:03

by Eric W. Biederman

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

Sven Schnelle <[email protected]> writes:

> 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.

As far as this goes I don't have any problem with this patch.

However it looks like you missed
fs/notify/inotify_user.c:inotify_table[].

Any chance you can add to the patch that verify things look ok and send
version 3?

Thanks,
Eric


> Fixes: f9c82a4ea89c ("Increase size of ucounts to atomic_long_t")
> Signed-off-by: Sven Schnelle <[email protected]>
> ---
> 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"),