cbcvebase.
CVE-2025-21925
published 2025-04-01

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…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
10.7th percentile
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: __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]

Affected

35 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
debianlinux-6.1< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < cd1c44327bbbd50fc24f2b38892f5f328b784d0fcd1c44327bbbd50fc24f2b38892f5f328b784d0f
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 13f3f872627f0f27c31245524fc11367756240ad13f3f872627f0f27c31245524fc11367756240ad
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9b6f083db141ece0024be01526aa05aa978811cb9b6f083db141ece0024be01526aa05aa978811cb
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 17f86e25431ebc15aa9245ff156414fdad47822d17f86e25431ebc15aa9245ff156414fdad47822d
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 416e8b4c20c6398044e93008deefd563289f477d416e8b4c20c6398044e93008deefd563289f477d
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0f764208dc24ea043c3e20194d32aebf94f8459c0f764208dc24ea043c3e20194d32aebf94f8459c
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 056e8a46d79e22983bae4267e0d9c52927076f46056e8a46d79e22983bae4267e0d9c52927076f46
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 64e6a754d33d31aa844b3ee66fb93ac84ca1565e64e6a754d33d31aa844b3ee66fb93ac84ca1565e
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.237-15.10.237-1
linuxlinux_kernel>= 0 < 6.1.133-16.1.133-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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