In the Linux kernel, the following vulnerability has been resolved:

usbnet: Fix linkwatch use-after-free on disconnect

usbnet uses the work usbnet_deferred_kevent() to perform tasks which may sleep. On disconnect, completion of the work was originally awaited in ->ndo_stop(). But in 2003, that was moved to ->disconnect() by historic commit "[PATCH] USB: usbnet, prevent exotic rtnl deadlock":

https://git.kernel.org/tglx/history/c/0f138bbfd83c

The change was made because back then, the kernel's workqueue implementation did not allow waiting for a single work. One had to wait for completion of *all* work by calling flush_scheduled_work(), and that could deadlock when waiting for usbnet_deferred_kevent() with rtnl_mutex held in ->ndo_stop().

The commit solved one problem but created another: It causes a use-after-free in USB Ethernet drivers aqc111.c, asix_devices.c, ax88179_178a.c, ch9200.c and smsc75xx.c:

* If the drivers receive a link change interrupt immediately before disconnect, they raise EVENT_LINK_RESET in their (non-sleepable) ->status() callback and schedule usbnet_deferred_kevent(). * usbnet_deferred_kevent() invokes the driver's ->link_reset() callback, which calls netif_carrier_{on,off}(). * That in turn schedules the work linkwatch_event().

Because usbnet_deferred_kevent() is awaited after unregister_netdev(), netif_carrier_{on,off}() may operate on an unregistered netdev and linkwatch_event() may run after free_netdev(), causing a use-after-fr…

In the Linux kernel, the following vulnerability has been resolved:

usbnet: Fix linkwatch use-after-free on disconnect

usbnet uses the work usbnet_deferred_kevent() to perform tasks which may sleep. On disconnect, completion of the work was originally awaited in ->ndo_stop(). But in 2003, that was moved to ->disconnect() by historic commit "[PATCH] USB: usbnet, prevent exotic rtnl deadlock":

https://git.kernel.org/tglx/history/c/0f138bbfd83c

The change was made because back then, the kernel's workqueue implementation did not allow waiting for a single work. One had to wait for completion of *all* work by calling flush_scheduled_work(), and that could deadlock when waiting for usbnet_deferred_kevent() with rtnl_mutex held in ->ndo_stop().

The commit solved one problem but created another: It causes a use-after-free in USB Ethernet drivers aqc111.c, asix_devices.c, ax88179_178a.c, ch9200.c and smsc75xx.c:

* If the drivers receive a link change interrupt immediately before disconnect, they raise EVENT_LINK_RESET in their (non-sleepable) ->status() callback and schedule usbnet_deferred_kevent(). * usbnet_deferred_kevent() invokes the driver's ->link_reset() callback, which calls netif_carrier_{on,off}(). * That in turn schedules the work linkwatch_event().

Because usbnet_deferred_kevent() is awaited after unregister_netdev(), netif_carrier_{on,off}() may operate on an unregistered netdev and linkwatch_event() may run after free_netdev(), causing a use-after-fr…

Affected: openEuler:20.03-LTS-SP4: kernel

The Linux Kernel, the operating system core itself. Security Fix(es):

In the Linux kernel, the following vulnerability has been resolved:

tipc: fix the msg->req tlv len check in tipc_nl_compat_name_table_dump_header

This is a follow-up for commit 974cb0e3e7c9 ("tipc: fix uninit-value in tipc_nl_compat_name_table_dump") where it should have type casted sizeof(..) to int to work when TLV_GET_DATA_LEN() returns a negative value.

syzbot reported a call trace because of it:

BUG: KMSAN: uninit-value in ... tipc_nl_compat_name_table_dump+0x841/0xea0 net/tipc/netlink_compat.c:934 __tipc_nl_compat_dumpit+0xab2/0x1320 net/tipc/netlink_compat.c:238 tipc_nl_compat_dumpit+0x991/0xb50 net/tipc/netlink_compat.c:321 tipc_nl_compat_recv+0xb6e/0x1640 net/tipc/netlink_compat.c:1324 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline] genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0x103f/0x1260 net/netlink/genetlink.c:792 netlink_rcv_skb+0x3a5/0x6c0 net/netlink/af_netlink.c:2501 genl_rcv+0x3c/0x50 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline](CVE-2022-49862)

In the Linux kernel, the following vulnerability has been resolved:

net: tun: Fix memory leaks of…

Security update for the Linux Kernel

Affected: Ubuntu:Pro:14.04:LTS: linux-azure, Ubuntu:Pro:14.04:LTS: linux, Ubuntu:Pro:14.04:LTS: linux-aws, Ubuntu:Pro:14.04:LTS: linux-lts-xenial, Ubuntu:Pro:16.04:LTS: linux-aws-hwe, Ubuntu:Pro:16.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-gcp, Ubuntu:Pro:16.04:LTS: linux-hwe, Ubuntu:Pro:16.04:LTS: linux-oracle, Ubuntu:Pro:16.04:LTS: linux and 146 more

In the Linux kernel, the following vulnerability has been resolved: usbnet: Fix linkwatch use-after-free on disconnect usbnet uses the work usbnet_deferred_kevent() to perform tasks which may sleep. On disconnect, completion of the work was originally awaited in ->ndo_stop(). But in 2003, that was moved to ->disconnect() by historic commit "[PATCH] USB: usbnet, prevent exotic rtnl deadlock": https://git.kernel.org/tglx/history/c/0f138bbfd83c The change was made because back then, the kernel's workqueue implementation did not allow waiting for a single work. One had to wait for completion of *all* work by calling flush_scheduled_work(), and that could deadlock when waiting for usbnet_deferred_kevent() with rtnl_mutex held in ->ndo_stop(). The commit solved one problem but created another: It causes a use-after-free in USB Ethernet drivers aqc111.c, asix_devices.c, ax88179_178a.c, ch9200.c and smsc75xx.c: * If the drivers receive a link change interrupt immediately before disconnect, they raise EVENT_LINK_RESET in their (non-sleepable) ->status() callback and schedule usbnet_deferred_kevent(). * usbnet_deferred_kevent() invokes the driver's ->link_reset() callback, which calls netif_carrier_{on,off}(). * That in turn schedules the work linkwatch_event(). Because usbnet_deferred_kevent() is awaited after unregister_netdev(), netif_carrier_{on,off}() may operate on an unregistered netdev and linkwatch_event() may run after free_netdev(), causing a use-after-free. In…

Ein lokaler Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen.