Address the following -Wstringop-overflow warnings seen when
built with ARM architecture and aspeed_g4_defconfig configuration
(notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler
warnings with no subsystems").
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
kernel/cgroup/cgroup.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index cd497b90e11a..1ee76e62eb98 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -1200,6 +1200,9 @@ static struct css_set *find_css_set(struct css_set *old_cset,
unsigned long key;
int ssid;
+ if (!CGROUP_HAS_SUBSYS_CONFIG)
+ return NULL;
+
lockdep_assert_held(&cgroup_mutex);
/* First see if we already have a cgroup group that matches
@@ -6045,6 +6048,9 @@ int __init cgroup_init(void)
struct cgroup_subsys *ss;
int ssid;
+ if (!CGROUP_HAS_SUBSYS_CONFIG)
+ return -EINVAL;
+
BUILD_BUG_ON(CGROUP_SUBSYS_COUNT > 16);
BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files));
BUG_ON(cgroup_init_cftypes(NULL, cgroup_psi_files));
--
2.34.1
On Wed, Jun 14, 2023 at 07:18:22PM -0600, Gustavo A. R. Silva wrote:
> Address the following -Wstringop-overflow warnings seen when
> built with ARM architecture and aspeed_g4_defconfig configuration
> (notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
> kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>
> These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler
> warnings with no subsystems").
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
Ah nice, this should reduce code size for the "0" case too.
Reviewed-by: Kees Cook <[email protected]>
--
Kees Cook
On Wed, Jun 14, 2023 at 07:18:22PM -0600, Gustavo A. R. Silva wrote:
> Address the following -Wstringop-overflow warnings seen when
> built with ARM architecture and aspeed_g4_defconfig configuration
> (notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
> kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>
> These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler
> warnings with no subsystems").
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
Applied to cgroup/for-6.5.
Thanks.
--
tejun
On 15/06/2023 03:18, Gustavo A. R. Silva wrote:
> Address the following -Wstringop-overflow warnings seen when
> built with ARM architecture and aspeed_g4_defconfig configuration
> (notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
> kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>
Hi,
This patch landed in next but causes boot failures on
Exynos ARMv7 board (32 bit) with systemd (exynos_defconfig):
NFS-Mount: 192.168.1.10:/srv/nfs/odroidhc1
Waiting 10 seconds for device /dev/nfs ...
ERROR: device '/dev/nfs' not found. Skipping fsck.
Mount cmd:
mount.nfs4 -o vers=4,nolock 192.168.1.10:/srv/nfs/odroidhc1 /new_root
:: running cleanup hook [udev]
[ 23.752917] systemd[1]: System time before build time, advancing clock.
[ 23.851828] systemd[1]: Failed to mount tmpfs at /sys/fs/cgroup: No such file or directory
[ 23.868459] systemd[1]: Failed to mount cgroup at /sys/fs/cgroup/systemd: No such file or directory
[!!!!!!] Failed to mount API filesystems.
[ 23.914562] systemd[1]: Freezing execution.
Full log:
https://krzk.eu/#/builders/21/builds/4110/steps/15/logs/serial0
Best regards,
Krzysztof
On 15/06/2023 02:18, Gustavo A. R. Silva wrote:
> Address the following -Wstringop-overflow warnings seen when
> built with ARM architecture and aspeed_g4_defconfig configuration
> (notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
> kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>
> These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler
> warnings with no subsystems").
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> kernel/cgroup/cgroup.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
> index cd497b90e11a..1ee76e62eb98 100644
> --- a/kernel/cgroup/cgroup.c
> +++ b/kernel/cgroup/cgroup.c
> @@ -1200,6 +1200,9 @@ static struct css_set *find_css_set(struct css_set *old_cset,
> unsigned long key;
> int ssid;
>
> + if (!CGROUP_HAS_SUBSYS_CONFIG)
> + return NULL;
> +
> lockdep_assert_held(&cgroup_mutex);
>
> /* First see if we already have a cgroup group that matches
> @@ -6045,6 +6048,9 @@ int __init cgroup_init(void)
> struct cgroup_subsys *ss;
> int ssid;
>
> + if (!CGROUP_HAS_SUBSYS_CONFIG)
> + return -EINVAL;
> +
> BUILD_BUG_ON(CGROUP_SUBSYS_COUNT > 16);
> BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files));
> BUG_ON(cgroup_init_cftypes(NULL, cgroup_psi_files));
This change (which landed in linux-next) causes a boot failure on my
(arm32) board because the cgroup filesystem isn't created which upsets
systemd:
[ 11.474767] systemd[1]: Failed to mount tmpfs at /sys/fs/cgroup: No such file or directory
[ 11.489933] systemd[1]: Failed to mount cgroup at /sys/fs/cgroup/systemd: No such file or directory
[!!!!!!] Failed to mount API filesystems.
Reverting this commit on the head of linux-next gets the board working
again.
Thanks,
Steve
Hi!
On 6/22/23 04:11, Steven Price wrote:
> On 15/06/2023 02:18, Gustavo A. R. Silva wrote:
>> Address the following -Wstringop-overflow warnings seen when
>> built with ARM architecture and aspeed_g4_defconfig configuration
>> (notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
>> kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>> kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>> kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>> kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>>
>> These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler
>> warnings with no subsystems").
>>
>> Signed-off-by: Gustavo A. R. Silva <[email protected]>
>> ---
>> kernel/cgroup/cgroup.c | 6 ++++++
>> 1 file changed, 6 insertions(+)
>>
>> diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
>> index cd497b90e11a..1ee76e62eb98 100644
>> --- a/kernel/cgroup/cgroup.c
>> +++ b/kernel/cgroup/cgroup.c
>> @@ -1200,6 +1200,9 @@ static struct css_set *find_css_set(struct css_set *old_cset,
>> unsigned long key;
>> int ssid;
>>
>> + if (!CGROUP_HAS_SUBSYS_CONFIG)
>> + return NULL;
>> +
>> lockdep_assert_held(&cgroup_mutex);
>>
>> /* First see if we already have a cgroup group that matches
>> @@ -6045,6 +6048,9 @@ int __init cgroup_init(void)
>> struct cgroup_subsys *ss;
>> int ssid;
>>
>> + if (!CGROUP_HAS_SUBSYS_CONFIG)
>> + return -EINVAL;
>> +
>> BUILD_BUG_ON(CGROUP_SUBSYS_COUNT > 16);
>> BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files));
>> BUG_ON(cgroup_init_cftypes(NULL, cgroup_psi_files));
>
> This change (which landed in linux-next) causes a boot failure on my
> (arm32) board because the cgroup filesystem isn't created which upsets
> systemd:
>
> [ 11.474767] systemd[1]: Failed to mount tmpfs at /sys/fs/cgroup: No such file or directory
> [ 11.489933] systemd[1]: Failed to mount cgroup at /sys/fs/cgroup/systemd: No such file or directory
> [!!!!!!] Failed to mount API filesystems.
>
> Reverting this commit on the head of linux-next gets the board working
> again.
Thanks for reporting this issue. I'll take a look.
--
Gustavo
Hi!
On 6/22/23 04:20, Krzysztof Kozlowski wrote:
> On 15/06/2023 03:18, Gustavo A. R. Silva wrote:
>> Address the following -Wstringop-overflow warnings seen when
>> built with ARM architecture and aspeed_g4_defconfig configuration
>> (notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
>> kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>> kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>> kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>> kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>>
>
> Hi,
>
> This patch landed in next but causes boot failures on
> Exynos ARMv7 board (32 bit) with systemd (exynos_defconfig):
>
> NFS-Mount: 192.168.1.10:/srv/nfs/odroidhc1
> Waiting 10 seconds for device /dev/nfs ...
> ERROR: device '/dev/nfs' not found. Skipping fsck.
> Mount cmd:
> mount.nfs4 -o vers=4,nolock 192.168.1.10:/srv/nfs/odroidhc1 /new_root
> :: running cleanup hook [udev]
> [ 23.752917] systemd[1]: System time before build time, advancing clock.
> [ 23.851828] systemd[1]: Failed to mount tmpfs at /sys/fs/cgroup: No such file or directory
> [ 23.868459] systemd[1]: Failed to mount cgroup at /sys/fs/cgroup/systemd: No such file or directory
> [!!!!!!] Failed to mount API filesystems.
> [ 23.914562] systemd[1]: Freezing execution.
>
> Full log:
> https://krzk.eu/#/builders/21/builds/4110/steps/15/logs/serial0
Thanks for reporting this issue. I'll take a look.
--
Gustavo
On Thu, Jun 22, 2023 at 08:09:03AM -0600, Gustavo A. R. Silva wrote:
> > Reverting this commit on the head of linux-next gets the board working
> > again.
>
> Thanks for reporting this issue. I'll take a look.
I'm reverting the commit from cgroup/for-6.5. Let's try again later.
Thanks.
--
tejun
Hi all,
I wonder if you have any suggestions on how to address this issue. As it seems that
my last attempt caused some boot failures[1][2].
At first, I thought that the right way to fix this was through a similar fix as this
one[3]. But it seems I'm missing something else that I cannot determine yet.
These -Wstringop-overflow warnings are mostly the last ones remaining before we can
finally enable this compiler option, globally.
Any help or advice on how to properly address this is greatly appreciated. :)
Thanks!
--
Gustavo
[1] https://lore.kernel.org/linux-hardening/[email protected]/
[2] https://lore.kernel.org/linux-hardening/[email protected]/
[3] https://git.kernel.org/linus/d20d30ebb199
On 6/14/23 19:18, Gustavo A. R. Silva wrote:
> Address the following -Wstringop-overflow warnings seen when
> built with ARM architecture and aspeed_g4_defconfig configuration
> (notice that under this configuration CGROUP_SUBSYS_COUNT == 0):
> kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
> kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
>
> These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler
> warnings with no subsystems").
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> kernel/cgroup/cgroup.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
> index cd497b90e11a..1ee76e62eb98 100644
> --- a/kernel/cgroup/cgroup.c
> +++ b/kernel/cgroup/cgroup.c
> @@ -1200,6 +1200,9 @@ static struct css_set *find_css_set(struct css_set *old_cset,
> unsigned long key;
> int ssid;
>
> + if (!CGROUP_HAS_SUBSYS_CONFIG)
> + return NULL;
> +
> lockdep_assert_held(&cgroup_mutex);
>
> /* First see if we already have a cgroup group that matches
> @@ -6045,6 +6048,9 @@ int __init cgroup_init(void)
> struct cgroup_subsys *ss;
> int ssid;
>
> + if (!CGROUP_HAS_SUBSYS_CONFIG)
> + return -EINVAL;
> +
> BUILD_BUG_ON(CGROUP_SUBSYS_COUNT > 16);
> BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files));
> BUG_ON(cgroup_init_cftypes(NULL, cgroup_psi_files));