CVE-2025-21801

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

net: ravb: Fix missing rtnl lock in suspend/resume path

Fix the suspend/resume path by ensuring the rtnl lock is held where

required. Calls to ravb_open, ravb_close and wol operations must be

performed under the rtnl lock to prevent conflicts with ongoing ndo

operations.

Without this fix, the following warning is triggered:

[ 39.032969] =============================

[ 39.032983] WARNING: suspicious RCU usage

[ 39.033019] -----------------------------

[ 39.033033] drivers/net/phy/phy_device.c:2004 suspicious

rcu_dereference_protected() usage!

...

[ 39.033597] stack backtrace:

[ 39.033613] CPU: 0 UID: 0 PID: 174 Comm: python3 Not tainted

6.13.0-rc7-next-20250116-arm64-renesas-00002-g35245dfdc62c #7

[ 39.033623] Hardware name: Renesas SMARC EVK version 2 based on

r9a08g045s33 (DT)

[ 39.033628] Call trace:

[ 39.033633] show_stack+0x14/0x1c (C)

[ 39.033652] dump_stack_lvl+0xb4/0xc4

[ 39.033664] dump_stack+0x14/0x1c

[ 39.033671] lockdep_rcu_suspicious+0x16c/0x22c

[ 39.033682] phy_detach+0x160/0x190

[ 39.033694] phy_disconnect+0x40/0x54

[ 39.033703] ravb_close+0x6c/0x1cc

[ 39.033714] ravb_suspend+0x48/0x120

[ 39.033721] dpm_run_callback+0x4c/0x14c

[ 39.033731] device_suspend+0x11c/0x4dc

[ 39.033740] dpm_suspend+0xdc/0x214

[ 39.033748] dpm_suspend_start+0x48/0x60

[ 39.033758] suspend_devices_and_enter+0x124/0x574

[ 39.033769] pm_suspend+0x1ac/0x274

[ 39.033778] state_store+0x88/0x124

[ 39.033788] kobj_attr_store+0x14/0x24

[ 39.033798] sysfs_kf_write+0x48/0x6c

[ 39.033808] kernfs_fop_write_iter+0x118/0x1a8

[ 39.033817] vfs_write+0x27c/0x378

[ 39.033825] ksys_write+0x64/0xf4

[ 39.033833] __arm64_sys_write+0x18/0x20

[ 39.033841] invoke_syscall+0x44/0x104

[ 39.033852] el0_svc_common.constprop.0+0xb4/0xd4

[ 39.033862] do_el0_svc+0x18/0x20

[ 39.033870] el0_svc+0x3c/0xf0

[ 39.033880] el0t_64_sync_handler+0xc0/0xc4

[ 39.033888] el0t_64_sync+0x154/0x158

[ 39.041274] ravb 11c30000.ethernet eth0: Link is Down