From: Aaron Thompson <dev@xxxxxxxxxx>
If bt_debugfs is not created successfully, which happens if either
CONFIG_DEBUG_FS or CONFIG_DEBUG_FS_ALLOW_ALL is unset, then iso_init()
returns early and does not set iso_inited to true. This means that a
subsequent call to iso_init() will result in duplicate calls to
proto_register(), bt_sock_register(), etc.
With CONFIG_LIST_HARDENED and CONFIG_BUG_ON_DATA_CORRUPTION enabled, the
duplicate call to proto_register() triggers this BUG():
list_add double add: new=ffffffffc0b280d0, prev=ffffffffbab56250,
next=ffffffffc0b280d0.
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:35!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 2 PID: 887 Comm: bluetoothd Not tainted 6.10.11-1-ao-desktop #1
RIP: 0010:__list_add_valid_or_report+0x9a/0xa0
...
__list_add_valid_or_report+0x9a/0xa0
proto_register+0x2b5/0x340
iso_init+0x23/0x150 [bluetooth]
set_iso_socket_func+0x68/0x1b0 [bluetooth]
kmem_cache_free+0x308/0x330
hci_sock_sendmsg+0x990/0x9e0 [bluetooth]
__sock_sendmsg+0x7b/0x80
sock_write_iter+0x9a/0x110
do_iter_readv_writev+0x11d/0x220
vfs_writev+0x180/0x3e0
do_writev+0xca/0x100
...
This change removes the early return. The check for iso_debugfs being
NULL was unnecessary, it is always NULL when iso_inited is false.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type")
Signed-off-by: Aaron Thompson <dev@xxxxxxxxxx>
---
net/bluetooth/iso.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c
index d5e00d0dd1a0..c9eefb43bf47 100644
--- a/net/bluetooth/iso.c
+++ b/net/bluetooth/iso.c
@@ -2301,13 +2301,9 @@ int iso_init(void)
hci_register_cb(&iso_cb);
- if (IS_ERR_OR_NULL(bt_debugfs))
- return 0;
-
- if (!iso_debugfs) {
+ if (!IS_ERR_OR_NULL(bt_debugfs))
iso_debugfs = debugfs_create_file("iso", 0444, bt_debugfs,
NULL, &iso_debugfs_fops);
- }
iso_inited = true;
--
2.39.5
