| Message ID | 20210323163141.v2.1.I6c4306f6e8ba3ccc9106067d4eb70092f8cb2a49@changeid (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2] Bluetooth: check for zapped sk before connecting | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Guessed tree name to be net-next |
| netdev/subject_prefix | warning | Target tree name not specified in the subject |
| netdev/cc_maintainers | success | CCed 7 of 7 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 17 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
Hi Archie, > There is a possibility of receiving a zapped sock on > l2cap_sock_connect(). This could lead to interesting crashes, one > such case is tearing down an already tore l2cap_sock as is happened > with this call trace: > > __dump_stack lib/dump_stack.c:15 [inline] > dump_stack+0xc4/0x118 lib/dump_stack.c:56 > register_lock_class kernel/locking/lockdep.c:792 [inline] > register_lock_class+0x239/0x6f6 kernel/locking/lockdep.c:742 > __lock_acquire+0x209/0x1e27 kernel/locking/lockdep.c:3105 > lock_acquire+0x29c/0x2fb kernel/locking/lockdep.c:3599 > __raw_spin_lock_bh include/linux/spinlock_api_smp.h:137 [inline] > _raw_spin_lock_bh+0x38/0x47 kernel/locking/spinlock.c:175 > spin_lock_bh include/linux/spinlock.h:307 [inline] > lock_sock_nested+0x44/0xfa net/core/sock.c:2518 > l2cap_sock_teardown_cb+0x88/0x2fb net/bluetooth/l2cap_sock.c:1345 > l2cap_chan_del+0xa3/0x383 net/bluetooth/l2cap_core.c:598 > l2cap_chan_close+0x537/0x5dd net/bluetooth/l2cap_core.c:756 > l2cap_chan_timeout+0x104/0x17e net/bluetooth/l2cap_core.c:429 > process_one_work+0x7e3/0xcb0 kernel/workqueue.c:2064 > worker_thread+0x5a5/0x773 kernel/workqueue.c:2196 > kthread+0x291/0x2a6 kernel/kthread.c:211 > ret_from_fork+0x4e/0x80 arch/x86/entry/entry_64.S:604 > > Signed-off-by: Archie Pusaka <apusaka@chromium.org> > Reported-by: syzbot+abfc0f5e668d4099af73@syzkaller.appspotmail.com > Reviewed-by: Alain Michaud <alainm@chromium.org> > Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org> > Reviewed-by: Guenter Roeck <groeck@chromium.org> > --- > > Changes in v2: > * Modify locking order for better visibility > > net/bluetooth/l2cap_sock.c | 8 ++++++++ > 1 file changed, 8 insertions(+) patch has been applied to bluetooth-next tree. Regards Marcel
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index f1b1edd0b697..c99d65ef13b1 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -179,9 +179,17 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, struct l2cap_chan *chan = l2cap_pi(sk)->chan; struct sockaddr_l2 la; int len, err = 0; + bool zapped; BT_DBG("sk %p", sk); + lock_sock(sk); + zapped = sock_flag(sk, SOCK_ZAPPED); + release_sock(sk); + + if (zapped) + return -EINVAL; + if (!addr || alen < offsetofend(struct sockaddr, sa_family) || addr->sa_family != AF_BLUETOOTH) return -EINVAL;