* [PATCH] cgroups: fix a serious bug in cgroupstats
@ 2008-11-19 8:14 Li Zefan
2008-11-19 8:25 ` Andrew Morton
` (2 more replies)
0 siblings, 3 replies; 10+ messages in thread
From: Li Zefan @ 2008-11-19 8:14 UTC (permalink / raw)
To: Andrew Morton; +Cc: Paul Menage, Balbir Singh, LKML, Linux Containers
Try this, and you'll get oops immediately:
# cd Documentation/accounting/
# gcc -o getdelays getdelays.c
# mount -t cgroup -o debug xxx /mnt
# ./getdelays -C /mnt/tasks
Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
not struct cgroup.
After the patch, it returns EINVAL if we try to get cgroupstats
from a normal file.
CC: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
---
kernel/cgroup.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 358e775..f6f5219 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
struct cgroup *cgrp;
struct cgroup_iter it;
struct task_struct *tsk;
+
/*
- * Validate dentry by checking the superblock operations
+ * Validate dentry by checking the superblock operations,
+ * and make sure it's a directory.
*/
- if (dentry->d_sb->s_op != &cgroup_ops)
+ if (dentry->d_sb->s_op != &cgroup_ops ||
+ !S_ISDIR(dentry->d_inode->i_mode))
goto err;
ret = 0;
--
1.5.4.rc3
^ permalink raw reply related [flat|nested] 10+ messages in thread* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
2008-11-19 8:14 [PATCH] cgroups: fix a serious bug in cgroupstats Li Zefan
@ 2008-11-19 8:25 ` Andrew Morton
2008-11-19 8:29 ` Li Zefan
` (2 more replies)
[not found] ` <4923CAF1.1020404-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
2008-11-19 22:31 ` Paul Menage
2 siblings, 3 replies; 10+ messages in thread
From: Andrew Morton @ 2008-11-19 8:25 UTC (permalink / raw)
To: Li Zefan; +Cc: Paul Menage, Balbir Singh, LKML, Linux Containers, stable
On Wed, 19 Nov 2008 16:14:41 +0800 Li Zefan <lizf@cn.fujitsu.com> wrote:
> Try this, and you'll get oops immediately:
I guess that's wrong.
> # cd Documentation/accounting/
> # gcc -o getdelays getdelays.c
> # mount -t cgroup -o debug xxx /mnt
> # ./getdelays -C /mnt/tasks
>
> Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
> not struct cgroup.
>
> After the patch, it returns EINVAL if we try to get cgroupstats
> from a normal file.
>
> CC: Balbir Singh <balbir@linux.vnet.ibm.com>
> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
> ---
> kernel/cgroup.c | 7 +++++--
> 1 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index 358e775..f6f5219 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
> struct cgroup *cgrp;
> struct cgroup_iter it;
> struct task_struct *tsk;
> +
> /*
> - * Validate dentry by checking the superblock operations
> + * Validate dentry by checking the superblock operations,
> + * and make sure it's a directory.
> */
> - if (dentry->d_sb->s_op != &cgroup_ops)
> + if (dentry->d_sb->s_op != &cgroup_ops ||
> + !S_ISDIR(dentry->d_inode->i_mode))
> goto err;
>
> ret = 0;
The patch applies OK to 2.6.25, 2.6.26 and to 2.6.27. I marked it as
needing backport to those kernel versions. Please let me know if that
was inappropriate.
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
2008-11-19 8:25 ` Andrew Morton
@ 2008-11-19 8:29 ` Li Zefan
[not found] ` <20081119002552.3840e3d2.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
2008-11-19 8:30 ` Balbir Singh
2 siblings, 0 replies; 10+ messages in thread
From: Li Zefan @ 2008-11-19 8:29 UTC (permalink / raw)
To: Andrew Morton; +Cc: Paul Menage, Balbir Singh, LKML, Linux Containers, stable
> The patch applies OK to 2.6.25, 2.6.26 and to 2.6.27. I marked it as
> needing backport to those kernel versions. Please let me know if that
> was inappropriate.
>
Forgot to mention this:
The bug exists from 2.6.24 (when cgroupstats is introduced) to now, though
I didn't test in all those versions. I guess not many people used cgroupstats,
so it never gets triggered.
I think it can be applied to 2.6.24 too.
^ permalink raw reply [flat|nested] 10+ messages in thread[parent not found: <20081119002552.3840e3d2.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>]
* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
[not found] ` <20081119002552.3840e3d2.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
@ 2008-11-19 8:29 ` Li Zefan
2008-11-19 8:30 ` Balbir Singh
1 sibling, 0 replies; 10+ messages in thread
From: Li Zefan @ 2008-11-19 8:29 UTC (permalink / raw)
To: Andrew Morton
Cc: Linux Containers, Paul Menage, LKML,
stable-DgEjT+Ai2ygdnm+yROfE0A, Balbir Singh
> The patch applies OK to 2.6.25, 2.6.26 and to 2.6.27. I marked it as
> needing backport to those kernel versions. Please let me know if that
> was inappropriate.
>
Forgot to mention this:
The bug exists from 2.6.24 (when cgroupstats is introduced) to now, though
I didn't test in all those versions. I guess not many people used cgroupstats,
so it never gets triggered.
I think it can be applied to 2.6.24 too.
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
[not found] ` <20081119002552.3840e3d2.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
2008-11-19 8:29 ` Li Zefan
@ 2008-11-19 8:30 ` Balbir Singh
1 sibling, 0 replies; 10+ messages in thread
From: Balbir Singh @ 2008-11-19 8:30 UTC (permalink / raw)
To: Andrew Morton
Cc: Linux Containers, Paul Menage, LKML,
stable-DgEjT+Ai2ygdnm+yROfE0A
Andrew Morton wrote:
> On Wed, 19 Nov 2008 16:14:41 +0800 Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org> wrote:
>
>> Try this, and you'll get oops immediately:
>
> I guess that's wrong.
>
>> # cd Documentation/accounting/
>> # gcc -o getdelays getdelays.c
>> # mount -t cgroup -o debug xxx /mnt
>> # ./getdelays -C /mnt/tasks
>>
>> Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
>> not struct cgroup.
>>
>> After the patch, it returns EINVAL if we try to get cgroupstats
>> from a normal file.
>>
>> CC: Balbir Singh <balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
>> Signed-off-by: Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
>> ---
>> kernel/cgroup.c | 7 +++++--
>> 1 files changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
>> index 358e775..f6f5219 100644
>> --- a/kernel/cgroup.c
>> +++ b/kernel/cgroup.c
>> @@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
>> struct cgroup *cgrp;
>> struct cgroup_iter it;
>> struct task_struct *tsk;
>> +
>> /*
>> - * Validate dentry by checking the superblock operations
>> + * Validate dentry by checking the superblock operations,
>> + * and make sure it's a directory.
>> */
>> - if (dentry->d_sb->s_op != &cgroup_ops)
>> + if (dentry->d_sb->s_op != &cgroup_ops ||
>> + !S_ISDIR(dentry->d_inode->i_mode))
>> goto err;
>>
>> ret = 0;
>
> The patch applies OK to 2.6.25, 2.6.26 and to 2.6.27. I marked it as
> needing backport to those kernel versions. Please let me know if that
> was inappropriate.
>
Thanks, it does need to be backported. Thanks Li for spotting the problem.
--
Balbir
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
2008-11-19 8:25 ` Andrew Morton
2008-11-19 8:29 ` Li Zefan
[not found] ` <20081119002552.3840e3d2.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
@ 2008-11-19 8:30 ` Balbir Singh
2 siblings, 0 replies; 10+ messages in thread
From: Balbir Singh @ 2008-11-19 8:30 UTC (permalink / raw)
To: Andrew Morton; +Cc: Li Zefan, Paul Menage, LKML, Linux Containers, stable
Andrew Morton wrote:
> On Wed, 19 Nov 2008 16:14:41 +0800 Li Zefan <lizf@cn.fujitsu.com> wrote:
>
>> Try this, and you'll get oops immediately:
>
> I guess that's wrong.
>
>> # cd Documentation/accounting/
>> # gcc -o getdelays getdelays.c
>> # mount -t cgroup -o debug xxx /mnt
>> # ./getdelays -C /mnt/tasks
>>
>> Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
>> not struct cgroup.
>>
>> After the patch, it returns EINVAL if we try to get cgroupstats
>> from a normal file.
>>
>> CC: Balbir Singh <balbir@linux.vnet.ibm.com>
>> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
>> ---
>> kernel/cgroup.c | 7 +++++--
>> 1 files changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
>> index 358e775..f6f5219 100644
>> --- a/kernel/cgroup.c
>> +++ b/kernel/cgroup.c
>> @@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
>> struct cgroup *cgrp;
>> struct cgroup_iter it;
>> struct task_struct *tsk;
>> +
>> /*
>> - * Validate dentry by checking the superblock operations
>> + * Validate dentry by checking the superblock operations,
>> + * and make sure it's a directory.
>> */
>> - if (dentry->d_sb->s_op != &cgroup_ops)
>> + if (dentry->d_sb->s_op != &cgroup_ops ||
>> + !S_ISDIR(dentry->d_inode->i_mode))
>> goto err;
>>
>> ret = 0;
>
> The patch applies OK to 2.6.25, 2.6.26 and to 2.6.27. I marked it as
> needing backport to those kernel versions. Please let me know if that
> was inappropriate.
>
Thanks, it does need to be backported. Thanks Li for spotting the problem.
--
Balbir
^ permalink raw reply [flat|nested] 10+ messages in thread
[parent not found: <4923CAF1.1020404-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>]
* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
[not found] ` <4923CAF1.1020404-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
@ 2008-11-19 8:25 ` Andrew Morton
2008-11-19 22:31 ` Paul Menage
1 sibling, 0 replies; 10+ messages in thread
From: Andrew Morton @ 2008-11-19 8:25 UTC (permalink / raw)
To: Li Zefan
Cc: Containers, LKML,
Linux-FOgKQjlUJ6BQetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA, Paul Menage,
stable-DgEjT+Ai2ygdnm+yROfE0A, Balbir Singh
On Wed, 19 Nov 2008 16:14:41 +0800 Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org> wrote:
> Try this, and you'll get oops immediately:
I guess that's wrong.
> # cd Documentation/accounting/
> # gcc -o getdelays getdelays.c
> # mount -t cgroup -o debug xxx /mnt
> # ./getdelays -C /mnt/tasks
>
> Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
> not struct cgroup.
>
> After the patch, it returns EINVAL if we try to get cgroupstats
> from a normal file.
>
> CC: Balbir Singh <balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
> Signed-off-by: Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
> ---
> kernel/cgroup.c | 7 +++++--
> 1 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index 358e775..f6f5219 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
> struct cgroup *cgrp;
> struct cgroup_iter it;
> struct task_struct *tsk;
> +
> /*
> - * Validate dentry by checking the superblock operations
> + * Validate dentry by checking the superblock operations,
> + * and make sure it's a directory.
> */
> - if (dentry->d_sb->s_op != &cgroup_ops)
> + if (dentry->d_sb->s_op != &cgroup_ops ||
> + !S_ISDIR(dentry->d_inode->i_mode))
> goto err;
>
> ret = 0;
The patch applies OK to 2.6.25, 2.6.26 and to 2.6.27. I marked it as
needing backport to those kernel versions. Please let me know if that
was inappropriate.
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
[not found] ` <4923CAF1.1020404-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
2008-11-19 8:25 ` Andrew Morton
@ 2008-11-19 22:31 ` Paul Menage
1 sibling, 0 replies; 10+ messages in thread
From: Paul Menage @ 2008-11-19 22:31 UTC (permalink / raw)
To: Li Zefan; +Cc: Linux Containers, Andrew Morton, LKML, Balbir Singh
On Wed, Nov 19, 2008 at 12:14 AM, Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org> wrote:
> Try this, and you'll get oops immediately:
> # cd Documentation/accounting/
> # gcc -o getdelays getdelays.c
> # mount -t cgroup -o debug xxx /mnt
> # ./getdelays -C /mnt/tasks
>
> Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
> not struct cgroup.
>
> After the patch, it returns EINVAL if we try to get cgroupstats
> from a normal file.
>
> CC: Balbir Singh <balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
> Signed-off-by: Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
Good catch, thanks.
Acked-by: Paul Menage <menage-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
> ---
> kernel/cgroup.c | 7 +++++--
> 1 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index 358e775..f6f5219 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
> struct cgroup *cgrp;
> struct cgroup_iter it;
> struct task_struct *tsk;
> +
> /*
> - * Validate dentry by checking the superblock operations
> + * Validate dentry by checking the superblock operations,
> + * and make sure it's a directory.
> */
> - if (dentry->d_sb->s_op != &cgroup_ops)
> + if (dentry->d_sb->s_op != &cgroup_ops ||
> + !S_ISDIR(dentry->d_inode->i_mode))
> goto err;
>
> ret = 0;
> --
> 1.5.4.rc3
>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] cgroups: fix a serious bug in cgroupstats
2008-11-19 8:14 [PATCH] cgroups: fix a serious bug in cgroupstats Li Zefan
2008-11-19 8:25 ` Andrew Morton
[not found] ` <4923CAF1.1020404-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
@ 2008-11-19 22:31 ` Paul Menage
2 siblings, 0 replies; 10+ messages in thread
From: Paul Menage @ 2008-11-19 22:31 UTC (permalink / raw)
To: Li Zefan; +Cc: Andrew Morton, Balbir Singh, LKML, Linux Containers
On Wed, Nov 19, 2008 at 12:14 AM, Li Zefan <lizf@cn.fujitsu.com> wrote:
> Try this, and you'll get oops immediately:
> # cd Documentation/accounting/
> # gcc -o getdelays getdelays.c
> # mount -t cgroup -o debug xxx /mnt
> # ./getdelays -C /mnt/tasks
>
> Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
> not struct cgroup.
>
> After the patch, it returns EINVAL if we try to get cgroupstats
> from a normal file.
>
> CC: Balbir Singh <balbir@linux.vnet.ibm.com>
> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Good catch, thanks.
Acked-by: Paul Menage <menage@google.com>
> ---
> kernel/cgroup.c | 7 +++++--
> 1 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index 358e775..f6f5219 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
> struct cgroup *cgrp;
> struct cgroup_iter it;
> struct task_struct *tsk;
> +
> /*
> - * Validate dentry by checking the superblock operations
> + * Validate dentry by checking the superblock operations,
> + * and make sure it's a directory.
> */
> - if (dentry->d_sb->s_op != &cgroup_ops)
> + if (dentry->d_sb->s_op != &cgroup_ops ||
> + !S_ISDIR(dentry->d_inode->i_mode))
> goto err;
>
> ret = 0;
> --
> 1.5.4.rc3
>
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] cgroups: fix a serious bug in cgroupstats
@ 2008-11-19 8:14 Li Zefan
0 siblings, 0 replies; 10+ messages in thread
From: Li Zefan @ 2008-11-19 8:14 UTC (permalink / raw)
To: Andrew Morton; +Cc: Linux Containers, Paul Menage, LKML, Balbir Singh
Try this, and you'll get oops immediately:
# cd Documentation/accounting/
# gcc -o getdelays getdelays.c
# mount -t cgroup -o debug xxx /mnt
# ./getdelays -C /mnt/tasks
Because a normal file's dentry->d_fsdata is a pointer to struct cftype,
not struct cgroup.
After the patch, it returns EINVAL if we try to get cgroupstats
from a normal file.
CC: Balbir Singh <balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
Signed-off-by: Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
---
kernel/cgroup.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 358e775..f6f5219 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
struct cgroup *cgrp;
struct cgroup_iter it;
struct task_struct *tsk;
+
/*
- * Validate dentry by checking the superblock operations
+ * Validate dentry by checking the superblock operations,
+ * and make sure it's a directory.
*/
- if (dentry->d_sb->s_op != &cgroup_ops)
+ if (dentry->d_sb->s_op != &cgroup_ops ||
+ !S_ISDIR(dentry->d_inode->i_mode))
goto err;
ret = 0;
--
1.5.4.rc3
^ permalink raw reply related [flat|nested] 10+ messages in thread
end of thread, other threads:[~2008-11-19 22:31 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-11-19 8:14 [PATCH] cgroups: fix a serious bug in cgroupstats Li Zefan
2008-11-19 8:25 ` Andrew Morton
2008-11-19 8:29 ` Li Zefan
[not found] ` <20081119002552.3840e3d2.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
2008-11-19 8:29 ` Li Zefan
2008-11-19 8:30 ` Balbir Singh
2008-11-19 8:30 ` Balbir Singh
[not found] ` <4923CAF1.1020404-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
2008-11-19 8:25 ` Andrew Morton
2008-11-19 22:31 ` Paul Menage
2008-11-19 22:31 ` Paul Menage
-- strict thread matches above, loose matches on Subject: below --
2008-11-19 8:14 Li Zefan
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