In the Linux kernel, the following vulnerability has been resolved:
xfrm: always flush state and policy upon NETDEV_UNREGISTER event
syzbot is reporting that "struct xfrm_state" refcount is leaking.
unregister_netdevice: waiting for netdevsim0 to become free. Usage count = 2
ref_tracker: netdev@ffff888052f24618 has 1/1 users at
__netdev_tracker_alloc include/linux/netdevice.h:4400 [inline]
netdev_tracker_alloc include/linux/netdevice.h:4412 [inline]
xfrm_dev_state_add+0x3a5/0x1080 net/xfrm/xfrm_device.c:316
xfrm_state_construct net/xfrm/xfrm_user.c:986 [inline]
xfrm_add_sa+0x34ff/0x5fa0 net/xfrm/xfrm_user.c:1022
xfrm_user_rcv_msg+0x58e/0xc00 net/xfrm/xfrm_user.c:3507
netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2550
xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3529
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592
___sys_sendmsg+0x134/0x1d0 net/socket.c:2646
__sys_sendmsg+0x16d/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
This is because commit d77e38e612a0 ("xfrm: Add an IPsec hardware
offloading API") implemented xfrm_dev_unregister() as no-op despite
xfrm_dev_state_add() from xfrm_state_construct() acquires a reference
to "struct net_device".
I guess that that commit expected that NETDEV_DOWN event is fired before
NETDEV_UNREGISTER event fires, and also assumed that xfrm_dev_state_add()
is called only if (dev->features & NETIF_F_HW_ESP) != 0.
Sabrina Dubroca identified steps to reproduce the same symptoms as below.
echo 0 > /sys/bus/netdevsim/new_device
dev=$(ls -1 /sys/bus/netdevsim/devices/netdevsim0/net/)
ip xfrm state add src 192.168.13.1 dst 192.168.13.2 proto esp \
spi 0x1000 mode tunnel aead 'rfc4106(gcm(aes))' $key 128 \
offload crypto dev $dev dir out
ethtool -K $dev esp-hw-offload off
echo 0 > /sys/bus/netdevsim/del_device
Like these steps indicate, the NETIF_F_HW_ESP bit can be cleared after
xfrm_dev_state_add() acquired a reference to "struct net_device".
Also, xfrm_dev_state_add() does not check for the NETIF_F_HW_ESP bit
when acquiring a reference to "struct net_device".
Commit 03891f820c21 ("xfrm: handle NETDEV_UNREGISTER for xfrm device")
re-introduced the NETDEV_UNREGISTER event to xfrm_dev_event(), but that
commit for unknown reason chose to share xfrm_dev_down() between the
NETDEV_DOWN event and the NETDEV_UNREGISTER event.
I guess that that commit missed the behavior in the previous paragraph.
Therefore, we need to re-introduce xfrm_dev_unregister() in order to
release the reference to "struct net_device" by unconditionally flushing
state and policy.
In the Linux kernel, the following vulnerability has been resolved:
xfs: remove xfs_attr_leaf_hasname
The calling convention of xfs_attr_leaf_hasname() is problematic, because
it returns a NULL buffer when xfs_attr3_leaf_read fails, a valid buffer
when xfs_attr3_leaf_lookup_int returns -ENOATTR or -EEXIST, and a
non-NULL buffer pointer for an already released buffer when
xfs_attr3_leaf_lookup_int fails with other error values.
Fix this by simply open coding xfs_attr_leaf_hasname in the callers, so
that the buffer release code is done by each caller of
xfs_attr3_leaf_read.
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix null dereference in find_network
The variable pwlan has the possibility of being NULL when passed into
rtw_free_network_nolock() which would later dereference the variable.
In the Linux kernel, the following vulnerability has been resolved:
mfd: core: Add locking around 'mfd_of_node_list'
Manipulating a list in the kernel isn't safe without some sort of
mutual exclusion. Add a mutex any time we access / modify
'mfd_of_node_list' to prevent possible crashes.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Fix null pointer dereference issue
If SMU is disabled, during RAS initialization,
there will be null pointer dereference issue here.
In the Linux kernel, the following vulnerability has been resolved:
fbcon: check return value of con2fb_acquire_newinfo()
If fbcon_open() fails when called from con2fb_acquire_newinfo() then
info->fbcon_par pointer remains NULL which is later dereferenced.
Add check for return value of the function con2fb_acquire_newinfo() to
avoid it.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
dlm: validate length in dlm_search_rsb_tree
The len parameter in dlm_dump_rsb_name() is not validated and comes
from network messages. When it exceeds DLM_RESNAME_MAXLEN, it can
cause out-of-bounds write in dlm_search_rsb_tree().
Add length validation to prevent potential buffer overflow.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: mixer: oss: Add card disconnect checkpoints
ALSA OSS mixer layer calls the kcontrol ops rather individually, and
pending calls might be not always caught at disconnecting the device.
For avoiding the potential UAF scenarios, add sanity checks of the
card disconnection at each entry point of OSS mixer accesses. The
rwsem is taken just before that check, hence the rest context should
be covered by that properly.
In the Linux kernel, the following vulnerability has been resolved:
most: core: fix resource leak in most_register_interface error paths
The function most_register_interface() did not correctly release resources
if it failed early (before registering the device). In these cases, it
returned an error code immediately, leaking the memory allocated for the
interface.
Fix this by initializing the device early via device_initialize() and
calling put_device() on all error paths.
The most_register_interface() is expected to call put_device() on
error which frees the resources allocated in the caller. The
put_device() either calls release_mdev() or dim2_release(),
depending on the caller.
Switch to using device_add() instead of device_register() to handle
the split initialization.
In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: Use devm_kmemdup() in rtw_set_supported_band()
Simplify the code by using device managed memory allocations.
This also fixes a memory leak in rtw_register_hw(). The supported bands
were not freed in the error path.
Copied from commit 145df52a8671 ("wifi: rtw89: Convert
rtw89_core_set_supported_band to use devm_*").