diff options
| author | Bui Viet Dung <dungvn2345@gmail.com> | 2026-10-08 12:11:29 +0700 |
|---|---|---|
| committer | Luiz Augusto von Dentz <luiz.von.dentz@intel.com> | 2026-10-14 14:38:23 -0400 |
| commit | 8368f0c2cde48c09ed70644059f24172b0c59f52 (patch) | |
| tree | a93f055cc5c39751469addb1190c3219dd7ff72c /net/bluetooth | |
| parent | ebba800d140b580540ad55f670d943e4a7edaffd (diff) | |
Bluetooth: 6lowpan: Pin module for 6lowpan_control debugfs file
An open debugfs file retains lowpan_control_fops in the debugfs proxy
state. However, lowpan_control_fops has no .owner set to THIS_MODULE.
As a result, full_proxy_open_regular() calls fops_get() which succeeds
without taking a reference to the bluetooth_6lowpan module.
With CONFIG_BT_6LOWPAN=m, a userspace process can keep the debugfs file
descriptor for 6lowpan_control open across module unload
(delete_module / rmmod bluetooth_6lowpan). When the process subsequently
closes the file descriptor, full_proxy_release() accesses the already
freed and unmapped lowpan_control_fops table, causing a kernel page fault
or oops.
The issue was discovered via manual code audit of
net/bluetooth/6lowpan.c.
Set .owner = THIS_MODULE on lowpan_control_fops so that debugfs pins
the module until all open file descriptors have finished.
Fixes: 6b8d4a6a0314 ("Bluetooth: 6LoWPAN: Use connected oriented channel instead of fixed one")
Cc: stable@vger.kernel.org
Signed-off-by: Bui Viet Dung <dungvn2345@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Diffstat (limited to 'net/bluetooth')
| -rw-r--r-- | net/bluetooth/6lowpan.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c index 6aaa2904d9dc..9a736cefac18 100644 --- a/net/bluetooth/6lowpan.c +++ b/net/bluetooth/6lowpan.c @@ -1215,6 +1215,7 @@ static int lowpan_control_open(struct inode *inode, struct file *file) } static const struct file_operations lowpan_control_fops = { + .owner = THIS_MODULE, .open = lowpan_control_open, .read = seq_read, .write = lowpan_control_write, |