CVE-2025-38250

{"id": "CVE-2025-38250", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2025-07-09T11:15:27.193", "references": [{"url": "https://git.kernel.org/stable/c/0e5c144c557df910ab64d9c25d06399a9a735e65", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/1d6123102e9fbedc8d25bf4731da6d513173e49e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/bc0819a25e04cd68ef3568cfa51b63118fea39a7", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ce23b73f0f27e2dbeb81734a79db710f05aa33c6", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_core: Fix use-after-free in vhci_flush()\n\nsyzbot reported use-after-free in vhci_flush() without repro. [0]\n\nFrom the splat, a thread close()d a vhci file descriptor while\nits device was being used by iotcl() on another thread.\n\nOnce the last fd refcnt is released, vhci_release() calls\nhci_unregister_dev(), hci_free_dev(), and kfree() for struct\nvhci_data, which is set to hci_dev->dev->driver_data.\n\nThe problem is that there is no synchronisation after unlinking\nhdev from hci_dev_list in hci_unregister_dev(). There might be\nanother thread still accessing the hdev which was fetched before\nthe unlink operation.\n\nWe can use SRCU for such synchronisation.\n\nLet's run hci_dev_reset() under SRCU and wait for its completion\nin hci_unregister_dev().\n\nAnother option would be to restore hci_dev->destruct(), which was\nremoved in commit 587ae086f6e4 (\"Bluetooth: Remove unused\nhci-destruct cb\"). However, this would not be a good solution, as\nwe should not run hci_unregister_dev() while there are in-flight\nioctl() requests, which could lead to another data-race KCSAN splat.\n\nNote that other drivers seem to have the same problem, for exmaple,\nvirtbt_remove().\n\n[0]:\nBUG: KASAN: slab-use-after-free in skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]\nBUG: KASAN: slab-use-after-free in skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937\nRead of size 8 at addr ffff88807cb8d858 by task syz.1.219/6718\n\nCPU: 1 UID: 0 PID: 6718 Comm: syz.1.219 Not tainted 6.16.0-rc1-syzkaller-00196-g08207f42d3ff #0 PREEMPT(full)\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025\nCall Trace:\n <TASK>\n dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120\n print_address_description mm/kasan/report.c:408 [inline]\n print_report+0xd2/0x2b0 mm/kasan/report.c:521\n kasan_report+0x118/0x150 mm/kasan/report.c:634\n skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]\n skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937\n skb_queue_purge include/linux/skbuff.h:3368 [inline]\n vhci_flush+0x44/0x50 drivers/bluetooth/hci_vhci.c:69\n hci_dev_do_reset net/bluetooth/hci_core.c:552 [inline]\n hci_dev_reset+0x420/0x5c0 net/bluetooth/hci_core.c:592\n sock_do_ioctl+0xd9/0x300 net/socket.c:1190\n sock_ioctl+0x576/0x790 net/socket.c:1311\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:907 [inline]\n __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7fcf5b98e929\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007fcf5c7b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010\nRAX: ffffffffffffffda RBX: 00007fcf5bbb6160 RCX: 00007fcf5b98e929\nRDX: 0000000000000000 RSI: 00000000400448cb RDI: 0000000000000009\nRBP: 00007fcf5ba10b39 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 0000000000000000 R14: 00007fcf5bbb6160 R15: 00007ffd6353d528\n </TASK>\n\nAllocated by task 6535:\n kasan_save_stack mm/kasan/common.c:47 [inline]\n kasan_save_track+0x3e/0x80 mm/kasan/common.c:68\n poison_kmalloc_redzone mm/kasan/common.c:377 [inline]\n __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394\n kasan_kmalloc include/linux/kasan.h:260 [inline]\n __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359\n kmalloc_noprof include/linux/slab.h:905 [inline]\n kzalloc_noprof include/linux/slab.h:1039 [inline]\n vhci_open+0x57/0x360 drivers/bluetooth/hci_vhci.c:635\n misc_open+0x2bc/0x330 drivers/char/misc.c:161\n chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414\n do_dentry_open+0xdf0/0x1970 fs/open.c:964\n vfs_open+0x3b/0x340 fs/open.c:1094\n do_open fs/namei.c:3887 [inline]\n path_openat+0x2ee5/0x3830 fs/name\n---truncated---"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: Bluetooth: hci_core: Se corrige el use-after-free en vhci_flush() syzbot inform\u00f3 use-after-free en vhci_flush() sin reproducci\u00f3n. [0] Desde el splat, un subproceso cierra() un descriptor de archivo vhci mientras su dispositivo estaba siendo usado por iotcl() en otro subproceso. Una vez que se libera el \u00faltimo fd refcnt, vhci_release() llama a hci_unregister_dev(), hci_free_dev() y kfree() para struct vhci_data, que est\u00e1 configurado en hci_dev-&gt;dev-&gt;driver_data. El problema es que no hay sincronizaci\u00f3n despu\u00e9s de desvincular hdev de hci_dev_list en hci_unregister_dev(). Podr\u00eda haber otro subproceso que a\u00fan acceda al hdev que se obtuvo antes de la operaci\u00f3n de desvinculaci\u00f3n. Podemos usar SRCU para dicha sincronizaci\u00f3n. Ejecutemos hci_dev_reset() en SRCU y esperemos a que se complete en hci_unregister_dev(). Otra opci\u00f3n ser\u00eda restaurar hci_dev-&gt;destruct(), que se elimin\u00f3 en el commit 587ae086f6e4 (\"Bluetooth: Eliminar el bloque de comandos hci-destruct no utilizado\"). Sin embargo, esta no ser\u00eda una buena soluci\u00f3n, ya que no deber\u00edamos ejecutar hci_unregister_dev() mientras haya solicitudes ioctl() en curso, lo que podr\u00eda provocar otro error de KCSAN en la ejecuci\u00f3n de datos. Tenga en cuenta que otros controladores parecen tener el mismo problema, por ejemplo, virtbt_remove(). [0]: ERROR: KASAN: slab-use-after-free en skb_queue_empty_lockless include/linux/skbuff.h:1891 [en l\u00ednea] ERROR: KASAN: slab-use-after-free en skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937 Lectura de tama\u00f1o 8 en la direcci\u00f3n ffff88807cb8d858 por la tarea syz.1.219/6718 CPU: 1 UID: 0 PID: 6718 Comm: syz.1.219 No contaminado 6.16.0-rc1-syzkaller-00196-g08207f42d3ff #0 PREEMPT(full) Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Rastreo de llamadas: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline] skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937 skb_queue_purge include/linux/skbuff.h:3368 [inline] vhci_flush+0x44/0x50 drivers/bluetooth/hci_vhci.c:69 hci_dev_do_reset net/bluetooth/hci_core.c:552 [inline] hci_dev_reset+0x420/0x5c0 net/bluetooth/hci_core.c:592 sock_do_ioctl+0xd9/0x300 net/socket.c:1190 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcf5b98e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcf5c7b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcf5bbb6160 RCX: 00007fcf5b98e929 RDX: 0000000000000000 RSI: 00000000400448cb RDI: 0000000000000009 RBP: 00007fcf5ba10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcf5bbb6160 R15: 00007ffd6353d528 Allocated by task 6535: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] vhci_open+0x57/0x360 drivers/bluetooth/hci_vhci.c:635 misc_open+0x2bc/0x330 drivers/char/misc.c:161 chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414 do_dentry_open+0xdf0/0x1970 fs/open.c:964 vfs_open+0x3b/0x340 fs/open.c:1094 ---truncado---"}], "lastModified": "2025-11-19T21:01:21.960", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B7D2126A-0CD0-4115-A75E-37D8FA8907ED", "versionEndExcluding": "6.6.97", "versionStartIncluding": "3.4"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2BD88DEC-018F-4F40-8E29-A2CA89813EBA", "versionEndExcluding": "6.12.36", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0CC768E2-3BBC-4A6E-9C2F-ECB27A703C2D", "versionEndExcluding": "6.15.5", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6D4894DB-CCFE-4602-B1BF-3960B2E19A01"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "09709862-E348-4378-8632-5A7813EDDC86"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "415BF58A-8197-43F5-B3D7-D1D63057A26E"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}