cbcvebase.
CVE-2025-38185
published 2025-07-04

CVE-2025-38185: In the Linux kernel, the following vulnerability has been resolved: atm: atmtcp: Free invalid length skb in atmtcp_c_send(). syzbot reported the splat below…

medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
In the Linux kernel, the following vulnerability has been resolved: atm: atmtcp: Free invalid length skb in atmtcp_c_send(). syzbot reported the splat below. [0] vcc_sendmsg() copies data passed from userspace to skb and passes it to vcc->dev->ops->send(). atmtcp_c_send() accesses skb->data as struct atmtcp_hdr after checking if skb->len is 0, but it's not enough. Also, when skb->len == 0, skb and sk (vcc) were leaked because dev_kfree_skb() is not called and sk_wmem_alloc adjustment is missing to revert atm_account_tx() in vcc_sendmsg(), which is expected to be done in atm_pop_raw(). Let's properly free skb with an invalid length in atmtcp_c_send(). [0]: BUG: KMSAN: uninit-value in atmtcp_c_send+0x255/0xed0 drivers/atm/atmtcp.c:294 atmtcp_c_send+0x255/0xed0 drivers/atm/atmtcp.c:294 vcc_sendmsg+0xd7c/0xff0 net/atm/common.c:644 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x330/0x3d0 net/socket.c:727 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2655 x64_sys_call+0x32fb/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4154 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4249 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1336 [inline] vcc_sendmsg+0xb40/0xff0 net/atm/common.c:628 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x330/0x3d0 net/socket.c:727 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inli

Affected

38 ranges· showing 25
VendorProductVersion rangeFixed in
debiandebian_linux
debianlinux< linux 6.1.147-1 (bookworm)linux 6.1.147-1 (bookworm)
debianlinux-6.1< linux 6.1.147-1 (bookworm)linux 6.1.147-1 (bookworm)
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c19c0943424b412a84fdf178e6c71fe5480e4f0fc19c0943424b412a84fdf178e6c71fe5480e4f0f
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a4b0fd8c25a7583f8564af6cc910418fb8954e89a4b0fd8c25a7583f8564af6cc910418fb8954e89
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1b0ad18704913c92a3ad53748fbc0f219a75b8761b0ad18704913c92a3ad53748fbc0f219a75b876
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ca00f0e6d733ecd9150716d1fd0138d26e674706ca00f0e6d733ecd9150716d1fd0138d26e674706
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3261c017a7c5d2815c6a388c5a3280d1fba0e8db3261c017a7c5d2815c6a388c5a3280d1fba0e8db
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < e996507f59610e5752b8702537f13f551e7a2c96e996507f59610e5752b8702537f13f551e7a2c96
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c9260c837de1d2b454960a4a2e44a81272fbcd22c9260c837de1d2b454960a4a2e44a81272fbcd22
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2f370ae1fb6317985f3497b1bb80d457508ca2f72f370ae1fb6317985f3497b1bb80d457508ca2f7
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.244-15.10.244-1
linuxlinux_kernel>= 0 < 6.1.147-16.1.147-1
linuxlinux_kernel>= 0 < 6.12.35-16.12.35-1
linuxlinux_kernel>= 0 < 6.12.35-16.12.35-1
linuxlinux_kernel>= 0 < 6.8.0-100.1006.8.0-100.100
linuxlinux_kernel>= 2.6.13 < 5.4.2955.4.295
linuxlinux_kernel>= 5.11 < 5.15.1865.15.186
linuxlinux_kernel>= 5.16 < 6.1.1426.1.142
linuxlinux_kernel>= 5.5 < 5.10.2395.10.239
linuxlinux_kernel>= 6.13 < 6.15.46.15.4
linuxlinux_kernel>= 6.2 < 6.6.956.6.95

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.6MEDIUM