Linux CVE-2026-72441

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

ieee802154: fix kernel-infoleak in dgram_recvmsg()

KMSAN reported a kernel-infoleak in move_addr_to_user():

BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:131 [inline] BUG: KMSAN: kernel-infoleak in _inline_copy_to_user include/linux/uaccess.h:205 [inline] BUG: KMSAN: kernel-infoleak in _copy_to_user+0xcc/0x120 lib/usercopy.c:26 instrument_copy_to_user include/linux/instrumented.h:131 [inline] _inline_copy_to_user include/linux/uaccess.h:205 [inline] _copy_to_user+0xcc/0x120 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:236 [inline] move_addr_to_user+0x2e7/0x440 net/socket.c:302 ____sys_recvmsg+0x232/0x610 net/socket.c:2925 ... Uninit was stored to memory at: ieee802154_addr_to_sa include/net/ieee802154_netdev.h:369 [inline] dgram_recvmsg+0xa09/0xbe0 net/ieee802154/socket.c:739

The issue occurs because the pan_id field of struct ieee802154_addr is left uninitialized when the address mode is IEEE802154_ADDR_NONE. The execution flow is as follows:

1. __ieee802154_rx_handle_packet() declares a local `struct

ieee802154_hdr hdr` on the stack.

1. ieee802154_hdr_pull() calls ieee802154_hdr_get_addr() to parse

the source and destination addresses into this structure.

1. If the address mode is IEEE802154_ADDR_NONE,

ieee802154_hdr_get_addr() previously only set the mode field, leaving the pan_id field containing uninitialized stack memory.

1. This uninitialized pan_id is later copied into a `struct

sockaddr_ieee802154 in dgram_recvmsg() via ieee802154_addr_to_sa()`.

1. Finally, move_addr_to_user() copies the socket address structure to

user space, leaking the uninitialized bytes.

Fix this by using memset to zero out the address structure in ieee802154_hdr_get_addr() when the mode is IEEE802154_ADDR_NONE.