[PATCH] fix mempolicy's check on a system with memory-less-node
bind_zonelist() can create zero-length zonelist if there is a
memory-less-node. This patch checks the length of zonelist. If length is
0, returns -EINVAL.
tested on ia64/NUMA with memory-less-node.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 259a706b..cf2a538 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -144,7 +144,7 @@
max++; /* space for zlcache_ptr (see mmzone.h) */
zl = kmalloc(sizeof(struct zone *) * max, GFP_KERNEL);
if (!zl)
- return NULL;
+ return ERR_PTR(-ENOMEM);
zl->zlcache_ptr = NULL;
num = 0;
/* First put in the highest zones from all nodes, then all the next
@@ -162,6 +162,10 @@
break;
k--;
}
+ if (num == 0) {
+ kfree(zl);
+ return ERR_PTR(-EINVAL);
+ }
zl->zones[num] = NULL;
return zl;
}
@@ -193,9 +197,10 @@
break;
case MPOL_BIND:
policy->v.zonelist = bind_zonelist(nodes);
- if (policy->v.zonelist == NULL) {
+ if (IS_ERR(policy->v.zonelist)) {
+ void *error_code = policy->v.zonelist;
kmem_cache_free(policy_cache, policy);
- return ERR_PTR(-ENOMEM);
+ return error_code;
}
break;
}
@@ -1667,7 +1672,7 @@
* then zonelist_policy() will "FALL THROUGH" to MPOL_DEFAULT.
*/
- if (zonelist) {
+ if (!IS_ERR(zonelist)) {
/* Good - got mem - substitute new zonelist */
kfree(pol->v.zonelist);
pol->v.zonelist = zonelist;
