SUSE: CVE-2025-38392: SUSE Linux Security Advisory

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

idpf: convert control queue mutex to a spinlock

With VIRTCHNL2_CAP_MACFILTER enabled, the following warning is generated
on module load:

[ 324.701677] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:578
[ 324.701684] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1582, name: NetworkManager
[ 324.701689] preempt_count: 201, expected: 0
[ 324.701693] RCU nest depth: 0, expected: 0
[ 324.701697] 2 locks held by NetworkManager/1582:
[ 324.701702] #0: ffffffff9f7be770 (rtnl_mutex){....}-{3:3}, at: rtnl_newlink+0x791/0x21e0
[ 324.701730] #1: ff1100216c380368 (_xmit_ETHER){....}-{2:2}, at: __dev_open+0x3f0/0x870
[ 324.701749] Preemption disabled at:
[ 324.701752] [<ffffffff9cd23b9d>] __dev_open+0x3dd/0x870
[ 324.701765] CPU: 30 UID: 0 PID: 1582 Comm: NetworkManager Not tainted 6.15.0-rc5+ #2 PREEMPT(voluntary)
[ 324.701771] Hardware name: Intel Corporation M50FCP2SBSTD/M50FCP2SBSTD, BIOS SE5C741.86B.01.01.0001.2211140926 11/14/2022
[ 324.701774] Call Trace:
[ 324.701777] <TASK>
[ 324.701779] dump_stack_lvl+0x5d/0x80
[ 324.701788] ? __dev_open+0x3dd/0x870
[ 324.701793] __might_resched.cold+0x1ef/0x23d
<..>
[ 324.701818] __mutex_lock+0x113/0x1b80
<..>
[ 324.701917] idpf_ctlq_clean_sq+0xad/0x4b0 [idpf]
[ 324.701935] ? kasan_save_track+0x14/0x30
[ 324.701941] idpf_mb_clean+0x143/0x380 [idpf]
<..>
[ 324.701991] idpf_send_mb_msg+0x111/0x720 [idpf]
[ 324.702009] idpf_vc_xn_exec+0x4cc/0x990 [idpf]
[ 324.702021] ? rcu_is_watching+0x12/0xc0
[ 324.702035] idpf_add_del_mac_filters+0x3ed/0xb50 [idpf]
<..>
[ 324.702122] __hw_addr_sync_dev+0x1cf/0x300
[ 324.702126] ? find_held_lock+0x32/0x90
[ 324.702134] idpf_set_rx_mode+0x317/0x390 [idpf]
[ 324.702152] __dev_open+0x3f8/0x870
[ 324.702159] ? __pfx___dev_open+0x10/0x10
[ 324.702174] __dev_change_flags+0x443/0x650
<..>
[ 324.702208] netif_change_flags+0x80/0x160
[ 324.702218] do_setlink.isra.0+0x16a0/0x3960
<..>
[ 324.702349] rtnl_newlink+0x12fd/0x21e0

The sequence is as follows:
rtnl_newlink()->
__dev_change_flags()->
__dev_open()->
dev_set_rx_mode() - > # disables BH and grabs "dev->addr_list_lock"
idpf_set_rx_mode() -> # proceed only if VIRTCHNL2_CAP_MACFILTER is ON
__dev_uc_sync() ->
idpf_add_mac_filter ->
idpf_add_del_mac_filters ->
idpf_send_mb_msg() ->
idpf_mb_clean() ->
idpf_ctlq_clean_sq() # mutex_lock(cq_lock)

Fix by converting cq_lock to a spinlock. All operations under the new
lock are safe except freeing the DMA memory, which may use vunmap(). Fix
by requesting a contiguous physical memory for the DMA mapping.