[PATCH] dmaengine: idxd: fix double free in idxd_alloc() error path

Guangshuo Li posted 1 patch 11 hours ago
drivers/dma/idxd/init.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[PATCH] dmaengine: idxd: fix double free in idxd_alloc() error path
Posted by Guangshuo Li 11 hours ago
When dev_set_name() fails after device_initialize(), idxd_alloc()
calls put_device(conf_dev).

For these devices, conf_dev->type is set from idxd->data->dev_type,
which resolves to dsa_device_type or iax_device_type, and both use
idxd_conf_device_release() as their release callback.

That release callback frees idxd, idxd->opcap_bmap, and releases
idxd->id, but the current error path then frees those resources again
directly, causing a double free.

Keep the cleanup in idxd_conf_device_release() after put_device() and
avoid freeing idxd-managed resources again in idxd_alloc().

Fixes: 46a5cca76c76 ("dmaengine: idxd: fix memory leak in error handling path of idxd_alloc")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
---
 drivers/dma/idxd/init.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
index 4eff74182225..94ce52565e7a 100644
--- a/drivers/dma/idxd/init.c
+++ b/drivers/dma/idxd/init.c
@@ -635,7 +635,7 @@ static struct idxd_device *idxd_alloc(struct pci_dev *pdev, struct idxd_driver_d
 
 err_name:
 	put_device(conf_dev);
-	bitmap_free(idxd->opcap_bmap);
+	return NULL;
 err_opcap:
 	ida_free(&idxd_ida, idxd->id);
 err_ida:
-- 
2.43.0