CVE-2026-98798
Description
In the Linux kernel, the following vulnerability has been resolved:
net: bcmgenet: fix NULL dereference in set_coalesce before first open
The Rx ring priv and index are only set in bcmgenet_init_rx_ring(),
which runs at open. Setting the Rx coalescing parameters on an interface
that was never opened, e.g. 'ethtool -C eth0 rx-usecs 50', dereferences
a NULL ring->priv. The oops happens with RTNL held, so networking
stays stuck until a reboot:
Unable to handle kernel paging request at virtual address 0000000000002788
pc : bcmgenet_set_rx_coalesce.isra.0+0x10/0x88
lr : bcmgenet_set_coalesce+0xe8/0x180
Call trace:
bcmgenet_set_rx_coalesce.isra.0+0x10/0x88 (P)
__ethnl_set_coalesce.isra.0+0x490/0x570
ethnl_set_coalesce+0x48/0xc0
ethnl_default_set_doit+0xf4/0x230
genl_family_rcv_msg_doit+0xe8/0x160
genl_rcv_msg+0x220/0x2a0
netlink_rcv_skb+0x68/0x140
genl_rcv+0x40/0x60
netlink_unicast+0x338/0x3c0
netlink_sendmsg+0x19c/0x3f8
__sock_sendmsg+0x64/0xc0
__sys_sendto+0x124/0x198
__arm64_sys_sendto+0x30/0x48
Set priv and index at probe. Writing the registers while the interface
is down is harmless because open resets the MAC and
bcmgenet_init_rx_coalesce() reapplies the stored values.
It was observed on a Raspberry Pi CM4, but should apply to all other
genet devices.
EPSS (Exploit Prediction Scoring System)
EPSS (Exploit Prediction Scoring System)
Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.