Lin Ma 8e34d07dd4 ax25: NPD bug when detaching AX25 device ... commit 1ade48d0c27d5da1ccf4b583d8c5fc8b534a3ac8 upstream. The existing cleanup routine implementation is not well synchronized with the syscall routine. When a device is detaching, below race could occur. static int ax25_sendmsg(...) { ... lock_sock() ax25 = sk_to_ax25(sk); if (ax25->ax25_dev == NULL) // CHECK ... ax25_queue_xmit(skb, ax25->ax25_dev->dev); // USE ... } static void ax25_kill_by_device(...) { ... if (s->ax25_dev == ax25_dev) { s->ax25_dev = NULL; ... } Other syscall functions like ax25_getsockopt, ax25_getname, ax25_info_show also suffer from similar races. To fix them, this patch introduce lock_sock() into ax25_kill_by_device in order to guarantee that the nullify action in cleanup routine cannot proceed when another socket request is pending. Signed-off-by: Hanjie Wu <nagi@zju.edu.cn> Signed-off-by: Lin Ma <linma@zju.edu.cn> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-12-29 12:26:07 +01:00
..
af_ax25.c	ax25: NPD bug when detaching AX25 device	2021-12-29 12:26:07 +01:00
ax25_addr.c
ax25_dev.c
ax25_ds_in.c
ax25_ds_subr.c
ax25_ds_timer.c
ax25_iface.c
ax25_in.c
ax25_ip.c
ax25_out.c
ax25_route.c
ax25_std_in.c
ax25_std_subr.c
ax25_std_timer.c
ax25_subr.c
ax25_timer.c
ax25_uid.c
Kconfig	AX.25 Kconfig: Replace HTTP links with HTTPS ones	2020-07-13 12:34:06 -07:00
Makefile
sysctl_net_ax25.c
TODO