--- id: CVE-2025-38245 title: 'atm: Release atm_dev_mutex after removing procfs in atm_dev_deregister().' summary: |- In the Linux kernel, the following vulnerability has been resolved: atm: Release atm_dev_mutex after removing procfs in atm_dev_deregister(). syzbot reported a warning below during atm_dev_register(). [0] Before creating a new device … severity: none vendor: Linux product: Linux affected: - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 2a8dcee649d12f69713f2589171a1caf6d4fa439 - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 4bb1bb438134d9ee6b97cc07289dd7c569092eec - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 26248d5d68c865b888d632162abbf8130645622c - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < b2e40fcfe1575faaa548f87614006d3fe44c779e - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < cabed6ba92a9a8c09da02a3f20e32ecd80989896 - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < ae539d963a17443ec54cba8a767e4ffa318264f4 - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 6922f1a048c090f10704bbef4a3a1e81932d2e0a - >- Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < a433791aeaea6e84df709e0b9584b9bbe040cd1c - Linux 2.6.15 ssvc: exploitation: none automatable: 'no' technicalImpact: partial timestamp: '2026-11-05T20:52:06.478724Z' published: '2025-07-09' updated: '2026-11-05' sourceUpdated: '2026-11-05T21:02:28.728Z' source: CVEORG sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-38245' references: - url: 'https://git.kernel.org/stable/c/2a8dcee649d12f69713f2589171a1caf6d4fa439' - url: 'https://git.kernel.org/stable/c/4bb1bb438134d9ee6b97cc07289dd7c569092eec' - url: 'https://git.kernel.org/stable/c/26248d5d68c865b888d632162abbf8130645622c' - url: 'https://git.kernel.org/stable/c/b2e40fcfe1575faaa548f87614006d3fe44c779e' - url: 'https://git.kernel.org/stable/c/cabed6ba92a9a8c09da02a3f20e32ecd80989896' - url: 'https://git.kernel.org/stable/c/ae539d963a17443ec54cba8a767e4ffa318264f4' - url: 'https://git.kernel.org/stable/c/6922f1a048c090f10704bbef4a3a1e81932d2e0a' - url: 'https://git.kernel.org/stable/c/a433791aeaea6e84df709e0b9584b9bbe040cd1c' tags: - cve.org epss: 0.00189 epssPercentile: 0.08602 ingestedAt: '2026-11-05T22:38:31.942Z' --- ## Overview In the Linux kernel, the following vulnerability has been resolved: atm: Release atm_dev_mutex after removing procfs in atm_dev_deregister(). syzbot reported a warning below during atm_dev_register(). [0] Before creating a new device and procfs/sysfs for it, atm_dev_register() looks up a duplicated device by __atm_dev_lookup(). These operations are done under atm_dev_mutex. However, when removing a device in atm_dev_deregister(), it releases the mutex just after removing the device from the list that __atm_dev_lookup() iterates over. So, there will be a small race window where the device does not exist on the device list but procfs/sysfs are still not removed, triggering the splat. Let's hold the mutex until procfs/sysfs are removed in atm_dev_deregister(). [0]: proc_dir_entry 'atm/atmtcp:0' already registered WARNING: CPU: 0 PID: 5919 at fs/proc/generic.c:377 proc_register+0x455/0x5f0 fs/proc/generic.c:377 Modules linked in: CPU: 0 UID: 0 PID: 5919 Comm: syz-executor284 Not tainted 6.16.0-rc2-syzkaller-00047-g52da431bf03b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:proc_register+0x455/0x5f0 fs/proc/generic.c:377 Code: 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 a2 01 00 00 48 8b 44 24 10 48 c7 c7 20 c0 c2 8b 48 8b b0 d8 00 00 00 e8 0c 02 1c ff 90 <0f> 0b 90 90 48 c7 c7 80 f2 82 8e e8 0b de 23 09 48 8b 4c 24 28 48 RSP: 0018:ffffc9000466fa30 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817ae248 RDX: ffff888026280000 RSI: ffffffff817ae255 RDI: 0000000000000001 RBP: ffff8880232bed48 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff888076ed2140 R13: dffffc0000000000 R14: ffff888078a61340 R15: ffffed100edda444 FS: 00007f38b3b0c6c0(0000) GS:ffff888124753000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f38b3bdf953 CR3: 0000000076d58000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: proc_create_data+0xbe/0x110 fs/proc/generic.c:585 atm_proc_dev_register+0x112/0x1e0 net/atm/proc.c:361 atm_dev_register+0x46d/0x890 net/atm/resources.c:113 atmtcp_create+0x77/0x210 drivers/atm/atmtcp.c:369 atmtcp_attach drivers/atm/atmtcp.c:403 [inline] atmtcp_ioctl+0x2f9/0xd60 drivers/atm/atmtcp.c:464 do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159 sock_do_ioctl+0x115/0x280 net/socket.c:1190 sock_ioctl+0x227/0x6b0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f38b3b74459 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f38b3b0c198 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f38b3bfe318 RCX: 00007f38b3b74459 RDX: 0000000000000000 RSI: 0000000000006180 RDI: 0000000000000005 RBP: 00007f38b3bfe310 R08: 65732f636f72702f R09: 65732f636f72702f R10: 65732f636f72702f R11: 0000000000000246 R12: 00007f38b3bcb0ac R13: 00007f38b3b0c1a0 R14: 0000200000000200 R15: 00007f38b3bcb03b ## Affected - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 2a8dcee649d12f69713f2589171a1caf6d4fa439` - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 4bb1bb438134d9ee6b97cc07289dd7c569092eec` - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 26248d5d68c865b888d632162abbf8130645622c` - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < b2e40fcfe1575faaa548f87614006d3fe44c779e` - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < cabed6ba92a9a8c09da02a3f20e32ecd80989896` - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < ae539d963a17443ec54cba8a767e4ffa318264f4` - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < 6922f1a048c090f10704bbef4a3a1e81932d2e0a` - `Linux >= 64bf69ddff7637b7ed7acf9b2a823cc0ee519439 < a433791aeaea6e84df709e0b9584b9bbe040cd1c` - `Linux 2.6.15` ## Remediation Refer to the linked advisories for vendor-supplied fixes and affected version ranges.