| Message ID | 1603969246-958334-2-git-send-email-valeriy.vdovin@virtuozzo.com |
|---|---|
| State | New |
| Series | "cgroup: do not use cgroup_mutex in cgroup_show_options" |
| Headers | show |
diff --git a/kernel/ve/ve.c b/kernel/ve/ve.c index db26cbd4..f61b1fe 100644 --- a/kernel/ve/ve.c +++ b/kernel/ve/ve.c @@ -595,9 +595,6 @@ static void ve_drop_context(struct ve_struct *ve) struct nsproxy *ve_ns = ve->ve_ns; struct net *net = ve->ve_netns; - put_css_set_taskexit(ve->root_css_set); - ve->root_css_set = NULL; - ve->ve_netns = NULL; put_net(net); @@ -606,6 +603,9 @@ static void ve_drop_context(struct ve_struct *ve) synchronize_rcu(); put_nsproxy(ve_ns); + put_css_set_taskexit(ve->root_css_set); + ve->root_css_set = NULL; + ve_hook_iterate_fini(VE_SHUTDOWN_CHAIN, ve); put_cred(ve->init_cred);
On 29.10.2020 14:00, Valeriy Vdovin wrote: > This fixes 87cb5fdb5b5c77ac617b46a0fe118a7d50a77b1c > In the mentioned patch in cgroup_show_options ve->ve_ns is checked to > ensure that ve->root_css_set is usable. But in ve_drop_context > root_css_set is being released before ve_ns, which is a bug. > root_css_set will now be set to NULL after ve_ns is released. > This reordering only affects the described piece of code in > cgroup_show_options. > > https://jira.sw.ru/browse/PSBM-121438 > > Signed-off-by: Valeriy Vdovin <valeriy.vdovin@virtuozzo.com> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> > --- > kernel/ve/ve.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/ve/ve.c b/kernel/ve/ve.c > index db26cbd4..f61b1fe 100644 > --- a/kernel/ve/ve.c > +++ b/kernel/ve/ve.c > @@ -595,9 +595,6 @@ static void ve_drop_context(struct ve_struct *ve) > struct nsproxy *ve_ns = ve->ve_ns; > struct net *net = ve->ve_netns; > > - put_css_set_taskexit(ve->root_css_set); > - ve->root_css_set = NULL; > - > ve->ve_netns = NULL; > put_net(net); > > @@ -606,6 +603,9 @@ static void ve_drop_context(struct ve_struct *ve) > synchronize_rcu(); > put_nsproxy(ve_ns); > > + put_css_set_taskexit(ve->root_css_set); > + ve->root_css_set = NULL; > + > ve_hook_iterate_fini(VE_SHUTDOWN_CHAIN, ve); > > put_cred(ve->init_cred); >
This fixes 87cb5fdb5b5c77ac617b46a0fe118a7d50a77b1c In the mentioned patch in cgroup_show_options ve->ve_ns is checked to ensure that ve->root_css_set is usable. But in ve_drop_context root_css_set is being released before ve_ns, which is a bug. root_css_set will now be set to NULL after ve_ns is released. This reordering only affects the described piece of code in cgroup_show_options. https://jira.sw.ru/browse/PSBM-121438 Signed-off-by: Valeriy Vdovin <valeriy.vdovin@virtuozzo.com> --- kernel/ve/ve.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)