A few drivers invoke dma_pool_create() with a null dev. Note that dev
is dereferenced in dev_to_node(dev), causing a null pointer dereference.
A long term solution is to disallow null dev. Once the drivers are
fixed, we can simplify the core code here. For now we add WARN_ON(!dev)
to notify the driver maintainers and avoid the null pointer dereference.
Suggested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Xi Wang <xi.wang@xxxxxxxxx>
---
mm/dmapool.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/mm/dmapool.c b/mm/dmapool.c
index c5ab33b..bf7f8f0 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -135,6 +135,7 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev,
{
struct dma_pool *retval;
size_t allocation;
+ int node;
if (align == 0) {
align = 1;
@@ -159,7 +160,9 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev,
return NULL;
}
- retval = kmalloc_node(sizeof(*retval), GFP_KERNEL, dev_to_node(dev));
+ node = WARN_ON(!dev) ? -1 : dev_to_node(dev);
+
+ retval = kmalloc_node(sizeof(*retval), GFP_KERNEL, node);
if (!retval)
return retval;
--
1.7.10.4
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>