lkml.org 
[lkml]   [2006]   [Aug]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[Patch] fix potential stack overflow in mm/slab.c
On High end systems (1024 or so cpus) this can potentially cause stack
overflow. Fix the stack usage.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>

--- linux-2.6.18-rc3/mm/slab.c~ 2006-08-03 15:00:40.634997600 -0700
+++ linux-2.6.18-rc3/mm/slab.c 2006-08-03 16:22:41.799866824 -0700
@@ -3603,22 +3603,27 @@ static void do_ccupdate_local(void *info
static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
int batchcount, int shared)
{
- struct ccupdate_struct new;
+ struct ccupdate_struct *new;
int i, err;

- memset(&new.new, 0, sizeof(new.new));
+ new = kmalloc(sizeof(*new), GFP_KERNEL);
+ if (!new)
+ return -ENOMEM;
+
+ memset(&new->new, 0, sizeof(new->new));
for_each_online_cpu(i) {
- new.new[i] = alloc_arraycache(cpu_to_node(i), limit,
+ new->new[i] = alloc_arraycache(cpu_to_node(i), limit,
batchcount);
- if (!new.new[i]) {
+ if (!new->new[i]) {
for (i--; i >= 0; i--)
- kfree(new.new[i]);
+ kfree(new->new[i]);
+ kfree(new);
return -ENOMEM;
}
}
- new.cachep = cachep;
+ new->cachep = cachep;

- on_each_cpu(do_ccupdate_local, (void *)&new, 1, 1);
+ on_each_cpu(do_ccupdate_local, (void *)new, 1, 1);

check_irq_on();
cachep->batchcount = batchcount;
@@ -3626,7 +3631,7 @@ static int do_tune_cpucache(struct kmem_
cachep->shared = shared;

for_each_online_cpu(i) {
- struct array_cache *ccold = new.new[i];
+ struct array_cache *ccold = new->new[i];
if (!ccold)
continue;
spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock);
@@ -3641,6 +3646,8 @@ static int do_tune_cpucache(struct kmem_
cachep->name, -err);
BUG();
}
+
+ kfree(new);
return 0;
}

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2006-08-04 03:47    [from the cache]
©2003-2011 Jasper Spaans. Advertise on this site