[PATCH 5.10 090/135] drivers core: Fix oops when driver probe fails

From: Greg Kroah-Hartman
Date: Tue Aug 10 2021 - 13:48:20 EST


From: Filip Schauer <filip@xxxxxx>

commit 4d1014c1816c0395eca5d1d480f196a4c63119d0 upstream.

dma_range_map is freed to early, which might cause an oops when
a driver probe fails.
Call trace:
is_free_buddy_page+0xe4/0x1d4
__free_pages+0x2c/0x88
dma_free_contiguous+0x64/0x80
dma_direct_free+0x38/0xb4
dma_free_attrs+0x88/0xa0
dmam_release+0x28/0x34
release_nodes+0x78/0x8c
devres_release_all+0xa8/0x110
really_probe+0x118/0x2d0
__driver_probe_device+0xc8/0xe0
driver_probe_device+0x54/0xec
__driver_attach+0xe0/0xf0
bus_for_each_dev+0x7c/0xc8
driver_attach+0x30/0x3c
bus_add_driver+0x17c/0x1c4
driver_register+0xc0/0xf8
__platform_driver_register+0x34/0x40
...

This issue is introduced by commit d0243bbd5dd3 ("drivers core:
Free dma_range_map when driver probe failed"). It frees
dma_range_map before the call to devres_release_all, which is too
early. The solution is to free dma_range_map only after
devres_release_all.

Fixes: d0243bbd5dd3 ("drivers core: Free dma_range_map when driver probe failed")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Filip Schauer <filip@xxxxxx>
Link: https://lore.kernel.org/r/20210727112311.GA7645@DESKTOP-E8BN1B0.localdomain
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/dd.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -617,8 +617,6 @@ dev_groups_failed:
else if (drv->remove)
drv->remove(dev);
probe_failed:
- kfree(dev->dma_range_map);
- dev->dma_range_map = NULL;
if (dev->bus)
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
@@ -626,6 +624,8 @@ pinctrl_bind_failed:
device_links_no_driver(dev);
devres_release_all(dev);
arch_teardown_dma_ops(dev);
+ kfree(dev->dma_range_map);
+ dev->dma_range_map = NULL;
driver_sysfs_remove(dev);
dev->driver = NULL;
dev_set_drvdata(dev, NULL);