Messages in this thread | ![/](/images/icornerl.gif) | | Date | Thu, 28 Oct 2010 21:22:07 +0530 | From | Balbir Singh <> | Subject | Re: [patch] memcg: null dereference on allocation failure |
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* Dan Carpenter <error27@gmail.com> [2010-10-28 13:12:41]:
> The original code had a null dereference if alloc_percpu() failed. > This was introduced in 711d3d2c9bc3 "memcg: cpu hotplug aware percpu > count updates" > > Signed-off-by: Dan Carpenter <error27@gmail.com> > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 9a99cfa..2efa8ea 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -4208,15 +4208,17 @@ static struct mem_cgroup *mem_cgroup_alloc(void) > > memset(mem, 0, size); > mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); > - if (!mem->stat) { > - if (size < PAGE_SIZE) > - kfree(mem); > - else > - vfree(mem); > - mem = NULL; > - } > + if (!mem->stat) > + goto out_free; > spin_lock_init(&mem->pcp_counter_lock); > return mem; > + > +out_free: > + if (size < PAGE_SIZE) > + kfree(mem); > + else > + vfree(mem); > + return NULL; > }
Good catch! Reviewed-by: Balbir Singh <balbir@linux.vnet.ibm.com>
-- Three Cheers, Balbir
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