CVE-2025-21925

In the Linux kernel, the following vulnerability has been resolved: llc: do not use skb_get() before dev_queue_xmit() syzbot is able to crash hosts [1], using llc and devices not supporting IFF_TX_SKB_SHARING. In this case, e1000 driver calls eth_skb_pad(), while the skb is shared. Simply replace skb_get() by skb_clone() in net/llc/llc_s_ac.c Note that e1000 driver might have an issue with pktgen, because it does not clear IFF_TX_SKB_SHARING, this is an orthogonal change. We need to audit other skb_get() uses in net/llc. [1] kernel BUG at net/core/skbuff.c:2178 ! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 0 UID: 0 PID: 16371 Comm: syz.2.2764 Not tainted 6.14.0-rc4-syzkaller-00052-gac9c34d1e45a #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:pskb_expand_head+0x6ce/0x1240 net/core/skbuff.c:2178 Call Trace: <TASK> __skb_pad+0x18a/0x610 net/core/skbuff.c:2466 __skb_put_padto include/linux/skbuff.h:3843 [inline] skb_put_padto include/linux/skbuff.h:3862 [inline] eth_skb_pad include/linux/etherdevice.h:656 [inline] e1000_xmit_frame+0x2d99/0x5800 drivers/net/ethernet/intel/e1000/e1000_main.c:3128 __netdev_start_xmit include/linux/netdevice.h:5151 [inline] netdev_start_xmit include/linux/netdevice.h:5160 [inline] xmit_one net/core/dev.c:3806 [inline] dev_hard_start_xmit+0x9a/0x7b0 net/core/dev.c:3822 sch_direct_xmit+0x1ae/0xc30 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:4045 [inline] __dev_queue_xmit+0x13d4/0x43e0 net/core/dev.c:4621 dev_queue_xmit include/linux/netdevice.h:3313 [inline] llc_sap_action_send_test_c+0x268/0x320 net/llc/llc_s_ac.c:144 llc_exec_sap_trans_actions net/llc/llc_sap.c:153 [inline] llc_sap_next_state net/llc/llc_sap.c:182 [inline] llc_sap_state_process+0x239/0x510 net/llc/llc_sap.c:209 llc_ui_sendmsg+0xd0d/0x14e0 net/llc/af_llc.c:993 sock_sendmsg_nosec net/socket.c:718 [inline]
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*

History

03 Nov 2025, 20:17

Type Values Removed Values Added
References
  • () https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html -
  • () https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html -

31 Oct 2025, 18:19

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: llc: no usar skb_get() antes de dev_queue_xmit(). syzbot puede bloquear hosts [1], usando llc y dispositivos que no admiten IFF_TX_SKB_SHARING. En este caso, el controlador e1000 llama a eth_skb_pad() mientras el skb está compartido. Simplemente reemplace skb_get() por skb_clone() en net/llc/llc_s_ac.c. Tenga en cuenta que el controlador e1000 podría tener un problema con pktgen, ya que no borra IFF_TX_SKB_SHARING; este es un cambio ortogonal. Necesitamos auditar otros usos de skb_get() en net/llc. [1] ¡ERROR del kernel en net/core/skbuff.c:2178! Oops: código de operación no válido: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 0 UID: 0 PID: 16371 Comm: syz.2.2764 No contaminado 6.14.0-rc4-syzkaller-00052-gac9c34d1e45a #0 Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 01/04/2014 RIP: 0010:pskb_expand_head+0x6ce/0x1240 net/core/skbuff.c:2178 Rastreo de llamadas: __skb_pad+0x18a/0x610 net/core/skbuff.c:2466 __skb_put_padto include/linux/skbuff.h:3843 [en línea] skb_put_padto include/linux/skbuff.h:3862 [en línea] eth_skb_pad include/linux/etherdevice.h:656 [en línea] e1000_xmit_frame+0x2d99/0x5800 drivers/net/ethernet/intel/e1000/e1000_main.c:3128 __netdev_start_xmit include/linux/netdevice.h:5151 [en línea] netdev_start_xmit include/linux/netdevice.h:5160 [en línea] xmit_one net/core/dev.c:3806 [en línea] dev_hard_start_xmit+0x9a/0x7b0 net/core/dev.c:3822 sch_direct_xmit+0x1ae/0xc30 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:4045 [en línea] __dev_queue_xmit+0x13d4/0x43e0 net/core/dev.c:4621 dev_queue_xmit include/linux/netdevice.h:3313 [en línea] llc_sap_action_send_test_c+0x268/0x320 net/llc/llc_s_ac.c:144 llc_exec_sap_trans_actions net/llc/llc_sap.c:153 [en línea] llc_sap_next_state net/llc/llc_sap.c:182 [en línea] llc_sap_state_process+0x239/0x510 net/llc/llc_sap.c:209 llc_ui_sendmsg+0xd0d/0x14e0 net/llc/af_llc.c:993 sock_sendmsg_nosec net/socket.c:718 [en línea]
First Time Linux
Linux linux Kernel
CPE cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5
CWE NVD-CWE-noinfo
References () https://git.kernel.org/stable/c/056e8a46d79e22983bae4267e0d9c52927076f46 - () https://git.kernel.org/stable/c/056e8a46d79e22983bae4267e0d9c52927076f46 - Patch
References () https://git.kernel.org/stable/c/0f764208dc24ea043c3e20194d32aebf94f8459c - () https://git.kernel.org/stable/c/0f764208dc24ea043c3e20194d32aebf94f8459c - Patch
References () https://git.kernel.org/stable/c/13f3f872627f0f27c31245524fc11367756240ad - () https://git.kernel.org/stable/c/13f3f872627f0f27c31245524fc11367756240ad - Patch
References () https://git.kernel.org/stable/c/17f86e25431ebc15aa9245ff156414fdad47822d - () https://git.kernel.org/stable/c/17f86e25431ebc15aa9245ff156414fdad47822d - Patch
References () https://git.kernel.org/stable/c/416e8b4c20c6398044e93008deefd563289f477d - () https://git.kernel.org/stable/c/416e8b4c20c6398044e93008deefd563289f477d - Patch
References () https://git.kernel.org/stable/c/64e6a754d33d31aa844b3ee66fb93ac84ca1565e - () https://git.kernel.org/stable/c/64e6a754d33d31aa844b3ee66fb93ac84ca1565e - Patch
References () https://git.kernel.org/stable/c/9b6f083db141ece0024be01526aa05aa978811cb - () https://git.kernel.org/stable/c/9b6f083db141ece0024be01526aa05aa978811cb - Patch
References () https://git.kernel.org/stable/c/cd1c44327bbbd50fc24f2b38892f5f328b784d0f - () https://git.kernel.org/stable/c/cd1c44327bbbd50fc24f2b38892f5f328b784d0f - Patch

01 Apr 2025, 16:15

Type Values Removed Values Added
New CVE

Information

Published : 2025-04-01 16:15

Updated : 2025-11-03 20:17


NVD link : CVE-2025-21925

Mitre link : CVE-2025-21925

CVE.ORG link : CVE-2025-21925


JSON object : View

Products Affected

linux

  • linux_kernel