#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f377d0025eb0
Early failures in Bluetooth HCI UART configuration leak SRCU percpu
memory.
When device initialization fails before hci_register_dev() completes,
the HCI_UNREGISTER flag is never set. As a result, when the device
reference count reaches zero, bt_host_release() evaluates this flag as
false and falls back to a direct kfree(hdev).
Because hci_release_dev() is bypassed, the SRCU struct initialized
early in hci_alloc_dev() is never cleaned up, resulting in a leak of
percpu memory.
Fix the leak by explicitly calling cleanup_srcu_struct() in the
fallback (unregistered) branch of bt_host_release() before freeing
the device.
Reported-by: syzbot+535ecc844591e50588a5@syzkaller.appspotmail.com
Signed-off-by: Bharath Reddy <kbreddy.rpbc@gmail.com>
---
net/bluetooth/hci_sysfs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
index 041ce9adc378..74131f2c3be6 100644
--- a/net/bluetooth/hci_sysfs.c
+++ b/net/bluetooth/hci_sysfs.c
@@ -85,8 +85,10 @@ static void bt_host_release(struct device *dev)
if (hci_dev_test_flag(hdev, HCI_UNREGISTER))
hci_release_dev(hdev);
- else
+ else {
+ cleanup_srcu_struct(&hdev->srcu);
kfree(hdev);
+ }
module_put(THIS_MODULE);
}
--
2.34.1