From 8af5e2eb3cc4450ffba9496c875beac41bf4f4f8 Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Tue, 20 Feb 2007 13:57:49 -0800 Subject: [PATCH] [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 Acked-by: Andi Kleen Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 259a706bd83e..cf2a5381030a 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -144,7 +144,7 @@ static struct zonelist *bind_zonelist(nodemask_t *nodes) 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 @@ static struct zonelist *bind_zonelist(nodemask_t *nodes) break; k--; } + if (num == 0) { + kfree(zl); + return ERR_PTR(-EINVAL); + } zl->zones[num] = NULL; return zl; } @@ -193,9 +197,10 @@ static struct mempolicy *mpol_new(int mode, nodemask_t *nodes) 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 @@ void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask) * 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; -- 2.30.2