CVE-2025-38185

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> atm: atmtcp: Free invalid length skb in atmtcp_c_send().<br /> <br /> syzbot reported the splat below. [0]<br /> <br /> vcc_sendmsg() copies data passed from userspace to skb and passes<br /> it to vcc-&gt;dev-&gt;ops-&gt;send().<br /> <br /> atmtcp_c_send() accesses skb-&gt;data as struct atmtcp_hdr after<br /> checking if skb-&gt;len is 0, but it&amp;#39;s not enough.<br /> <br /> Also, when skb-&gt;len == 0, skb and sk (vcc) were leaked because<br /> dev_kfree_skb() is not called and sk_wmem_alloc adjustment is missing<br /> to revert atm_account_tx() in vcc_sendmsg(), which is expected<br /> to be done in atm_pop_raw().<br /> <br /> Let&amp;#39;s properly free skb with an invalid length in atmtcp_c_send().<br /> <br /> [0]:<br /> BUG: KMSAN: uninit-value in atmtcp_c_send+0x255/0xed0 drivers/atm/atmtcp.c:294<br /> atmtcp_c_send+0x255/0xed0 drivers/atm/atmtcp.c:294<br /> vcc_sendmsg+0xd7c/0xff0 net/atm/common.c:644<br /> sock_sendmsg_nosec net/socket.c:712 [inline]<br /> __sock_sendmsg+0x330/0x3d0 net/socket.c:727<br /> ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566<br /> ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620<br /> __sys_sendmsg net/socket.c:2652 [inline]<br /> __do_sys_sendmsg net/socket.c:2657 [inline]<br /> __se_sys_sendmsg net/socket.c:2655 [inline]<br /> __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2655<br /> x64_sys_call+0x32fb/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:47<br /> do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]<br /> do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94<br /> entry_SYSCALL_64_after_hwframe+0x77/0x7f<br /> <br /> Uninit was created at:<br /> slab_post_alloc_hook mm/slub.c:4154 [inline]<br /> slab_alloc_node mm/slub.c:4197 [inline]<br /> kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4249<br /> kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579<br /> __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670<br /> alloc_skb include/linux/skbuff.h:1336 [inline]<br /> vcc_sendmsg+0xb40/0xff0 net/atm/common.c:628<br /> sock_sendmsg_nosec net/socket.c:712 [inline]<br /> __sock_sendmsg+0x330/0x3d0 net/socket.c:727<br /> ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566<br /> ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620<br /> __sys_sendmsg net/socket.c:2652 [inline]<br /> __do_sys_sendmsg net/socket.c:2657 [inline]<br /> __se_sys_sendmsg net/socket.c:2655 [inline]<br /> __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2655<br /> x64_sys_call+0x32fb/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:47<br /> do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]<br /> do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94<br /> entry_SYSCALL_64_after_hwframe+0x77/0x7f<br /> <br /> CPU: 1 UID: 0 PID: 5798 Comm: syz-executor192 Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(undef)<br /> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025