Eric Lee / smarc-ti-linux-kernel

Download as
Browse Code ยป

Commit 63f74ca21f1fad36d075e063f06dcc6d39fe86b2

Authored by KOSAKI Motohiro
Committed by Linus Torvalds
1 parent b22d127a39
Exists in master and in 20 other branches dlt-processor-sdk-linux-03.00.00.04, newt-ti-linux-3.12.y, processor-sdk-linux-01.00.00, processor-sdk-linux-02.00.01, smarc-ti-linux-3.12.10, smarc-ti-linux-3.12.y, smarc-ti-linux-3.14.y, smarc-ti-linux-3.15.y, smarc-ti-lsk-linux-4.1.y, smarct3x-processor-sdk-04.01.00.06, smarct3x-processor-sdk-linux-02.00.01, smarct3x-processor-sdk-linux-03.00.00.04, smarct4x-800-processor-sdk-linux-02.00.01, smarct4x-processor-sdk-04.01.00.06, smarct4x-processor-sdk-linux-02.00.01, smarct4x-processor-sdk-linux-03.00.00.04, ti-linux-3.12.y, ti-linux-3.14.y, ti-linux-3.15.y, ti-lsk-linux-4.1.y

mempolicy: fix refcount leak in mpol_set_shared_policy() 

When shared_policy_replace() fails to allocate new->policy is not freed
correctly by mpol_set_shared_policy().  The problem is that shared
mempolicy code directly call kmem_cache_free() in multiple places where
it is easy to make a mistake.

This patch creates an sp_free wrapper function and uses it. The bug was
introduced pre-git age (IOW, before 2.6.12-rc2).

[mgorman@suse.de: Editted changelog]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Showing 1 changed file with 9 additions and 6 deletions Side-by-side Diff

... ... @@ -2157,12 +2157,17 @@
2157 2157 return pol;
2158 2158 }
2159 2159  
  2160 +static void sp_free(struct sp_node *n)
  2161 +{
  2162 + mpol_put(n->policy);
  2163 + kmem_cache_free(sn_cache, n);
  2164 +}
  2165 +
2160 2166 static void sp_delete(struct shared_policy *sp, struct sp_node *n)
2161 2167 {
2162 2168 pr_debug("deleting %lx-l%lx\n", n->start, n->end);
2163 2169 rb_erase(&n->nd, &sp->root);
2164   - mpol_put(n->policy);
2165   - kmem_cache_free(sn_cache, n);
  2170 + sp_free(n);
2166 2171 }
2167 2172  
2168 2173 static struct sp_node *sp_alloc(unsigned long start, unsigned long end,
... ... @@ -2301,7 +2306,7 @@
2301 2306 }
2302 2307 err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new);
2303 2308 if (err && new)
2304   - kmem_cache_free(sn_cache, new);
  2309 + sp_free(new);
2305 2310 return err;
2306 2311 }
2307 2312  
... ... @@ -2318,9 +2323,7 @@
2318 2323 while (next) {
2319 2324 n = rb_entry(next, struct sp_node, nd);
2320 2325 next = rb_next(&n->nd);
2321   - rb_erase(&n->nd, &p->root);
2322   - mpol_put(n->policy);
2323   - kmem_cache_free(sn_cache, n);
  2326 + sp_delete(p, n);
2324 2327 }
2325 2328 mutex_unlock(&p->mutex);
2326 2329 }