CVSS: -EPSS: 0%CPEs: 2EXPL: 0CVE-2024-36892 – mm/slub: avoid zeroing outside-object freepointer for single free
https://notcve.org/view.php?id=CVE-2024-36892
In the Linux kernel, the following vulnerability has been resolved: mm/slub: avoid zeroing outside-object freepointer for single free Commit 284f17ac13fe ("mm/slub: handle bulk and single object freeing separately") splits single and bulk object freeing in two functions slab_free() and slab_free_bulk() which leads slab_free() to call slab_free_hook() directly instead of slab_free_freelist_hook(). If `init_on_free` is set, slab_free_hook() zeroes the object. Afterward, if `slub_debug=F` and `CONFIG_SLAB_FREELIST_HARDENED` are set, the do_slab_free() slowpath executes freelist consistency checks and try to decode a zeroed freepointer which leads to a "Freepointer corrupt" detection in check_object(). During bulk free, slab_free_freelist_hook() isn't affected as it always sets it objects freepointer using set_freepointer() to maintain its reconstructed freelist after `init_on_free`. For single free, object's freepointer thus needs to be avoided when stored outside the object if `init_on_free` is set. The freepointer left as is, check_object() may later detect an invalid pointer value due to objects overflow. To reproduce, set `slub_debug=FU init_on_free=1 log_level=7` on the command line of a kernel build with `CONFIG_SLAB_FREELIST_HARDENED=y`. dmesg sample log: [ 10.708715] ============================================================================= [ 10.710323] BUG kmalloc-rnd-05-32 (Tainted: G B T ): Freepointer corrupt [ 10.712695] ----------------------------------------------------------------------------- [ 10.712695] [ 10.712695] Slab 0xffffd8bdc400d580 objects=32 used=4 fp=0xffff9d9a80356f80 flags=0x200000000000a00(workingset|slab|node=0|zone=2) [ 10.716698] Object 0xffff9d9a80356600 @offset=1536 fp=0x7ee4f480ce0ecd7c [ 10.716698] [ 10.716698] Bytes b4 ffff9d9a803565f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.720703] Object ffff9d9a80356600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.720703] Object ffff9d9a80356610: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.724696] Padding ffff9d9a8035666c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.724696] Padding ffff9d9a8035667c: 00 00 00 00 .... [ 10.724696] FIX kmalloc-rnd-05-32: Object at 0xffff9d9a80356600 not freed En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm/slub: evita poner a cero el puntero libre de objetos externos para un solo commit libre 284f17ac13fe ("mm/slub: maneja la liberación masiva y de objetos individuales por separado") divide la liberación de objetos únicos y masivos en dos funciones slab_free() y slab_free_bulk() lo que lleva a slab_free() a llamar a slab_free_hook() directamente en lugar de slab_free_freelist_hook(). Si se establece `init_on_free`, slab_free_hook() pone a cero el objeto. Luego, si se configuran `slub_debug=F` y `CONFIG_SLAB_FREELIST_HARDENED`, la ruta lenta do_slab_free() ejecuta comprobaciones de coherencia de la lista libre e intenta decodificar un freepointer puesto a cero, lo que conduce a una detección de "Freepointer corrupto" en check_object(). Durante la liberación masiva, slab_free_freelist_hook() no se ve afectado ya que siempre establece el puntero libre de sus objetos usando set_freepointer() para mantener su lista libre reconstruida después de `init_on_free`. • https://git.kernel.org/stable/c/284f17ac13fe34ae9eecbe57bb91553374d9b855 https://git.kernel.org/stable/c/56900355485f6e82114b18c812edd57fd7970dcb https://git.kernel.org/stable/c/8f828aa48812ced28aa39cb3cfe55ef2444d03dd •
CVSS: 5.5EPSS: 0%CPEs: 4EXPL: 0CVE-2024-36891 – maple_tree: fix mas_empty_area_rev() null pointer dereference
https://notcve.org/view.php?id=CVE-2024-36891
In the Linux kernel, the following vulnerability has been resolved: maple_tree: fix mas_empty_area_rev() null pointer dereference Currently the code calls mas_start() followed by mas_data_end() if the maple state is MA_START, but mas_start() may return with the maple state node == NULL. This will lead to a null pointer dereference when checking information in the NULL node, which is done in mas_data_end(). Avoid setting the offset if there is no node by waiting until after the maple state is checked for an empty or single entry state. A user could trigger the events to cause a kernel oops by unmapping all vmas to produce an empty maple tree, then mapping a vma that would cause the scenario described above. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: maple_tree: corrige la desreferencia del puntero nulo mas_empty_area_rev() Actualmente el código llama a mas_start() seguido de mas_data_end() si el estado del arce es MA_START, pero mas_start() puede regresar con el estado del arce nodo == NULL. Esto dará lugar a una desreferencia del puntero nulo al verificar la información en el nodo NULL, lo cual se realiza en mas_data_end(). Evite establecer el desplazamiento si no hay ningún nodo esperando hasta que se verifique el estado del arce para detectar un estado vacío o de entrada única. • https://git.kernel.org/stable/c/54a611b605901c7d5d05b6b8f5d04a6ceb0962aa https://git.kernel.org/stable/c/883e5d542bbdddbddeba60250cb482baf3ae2415 https://git.kernel.org/stable/c/6c9c7c1e63b198a8b979ad963eb21410f10ccb00 https://git.kernel.org/stable/c/f3956791cf526540addd3295e4c1e0f0442486cc https://git.kernel.org/stable/c/955a923d2809803980ff574270f81510112be9cf https://access.redhat.com/security/cve/CVE-2024-36891 https://bugzilla.redhat.com/show_bug.cgi?id=2284567 • CWE-476: NULL Pointer Dereference •
CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2024-36890 – mm/slab: make __free(kfree) accept error pointers
https://notcve.org/view.php?id=CVE-2024-36890
In the Linux kernel, the following vulnerability has been resolved: mm/slab: make __free(kfree) accept error pointers Currently, if an automatically freed allocation is an error pointer that will lead to a crash. An example of this is in wm831x_gpio_dbg_show(). 171 char *label __free(kfree) = gpiochip_dup_line_label(chip, i); 172 if (IS_ERR(label)) { 173 dev_err(wm831x->dev, "Failed to duplicate label\n"); 174 continue; 175 } The auto clean up function should check for error pointers as well, otherwise we're going to keep hitting issues like this. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm/slab: make __free(kfree) acepta punteros de error Actualmente, si una asignación liberada automáticamente es un puntero de error que provocará un bloqueo. Un ejemplo de esto está en wm831x_gpio_dbg_show(). 171 caracteres *etiqueta __free(kfree) = gpiochip_dup_line_label(chip, i); 172 if (IS_ERR(etiqueta)) { 173 dev_err(wm831x->dev, "Error al duplicar la etiqueta\n"); 174 continúan; 175 } La función de limpieza automática también debería comprobar si hay indicadores de error; de lo contrario, seguiremos teniendo problemas como este. • https://git.kernel.org/stable/c/3c6cc62ce1265aa5623e2e1b29c0fe258bf6e232 https://git.kernel.org/stable/c/54da6a0924311c7cf5015533991e44fb8eb12773 https://git.kernel.org/stable/c/9f6eb0ab4f95240589ee85fd9886a944cd3645b2 https://git.kernel.org/stable/c/ac6cf3ce9b7d12acb7b528248df5f87caa25fcdc https://git.kernel.org/stable/c/79cbe0be6c0317b215ddd8bd3e32f0afdac48543 https://git.kernel.org/stable/c/cd7eb8f83fcf258f71e293f7fc52a70be8ed0128 •
CVSS: 5.5EPSS: 0%CPEs: 6EXPL: 0CVE-2024-36889 – mptcp: ensure snd_nxt is properly initialized on connect
https://notcve.org/view.php?id=CVE-2024-36889
In the Linux kernel, the following vulnerability has been resolved: mptcp: ensure snd_nxt is properly initialized on connect Christoph reported a splat hinting at a corrupted snd_una: WARNING: CPU: 1 PID: 38 at net/mptcp/protocol.c:1005 __mptcp_clean_una+0x4b3/0x620 net/mptcp/protocol.c:1005 Modules linked in: CPU: 1 PID: 38 Comm: kworker/1:1 Not tainted 6.9.0-rc1-gbbeac67456c9 #59 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 Workqueue: events mptcp_worker RIP: 0010:__mptcp_clean_una+0x4b3/0x620 net/mptcp/protocol.c:1005 Code: be 06 01 00 00 bf 06 01 00 00 e8 a8 12 e7 fe e9 00 fe ff ff e8 8e 1a e7 fe 0f b7 ab 3e 02 00 00 e9 d3 fd ff ff e8 7d 1a e7 fe <0f> 0b 4c 8b bb e0 05 00 00 e9 74 fc ff ff e8 6a 1a e7 fe 0f 0b e9 RSP: 0018:ffffc9000013fd48 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff8881029bd280 RCX: ffffffff82382fe4 RDX: ffff8881003cbd00 RSI: ffffffff823833c3 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: fefefefefefefeff R12: ffff888138ba8000 R13: 0000000000000106 R14: ffff8881029bd908 R15: ffff888126560000 FS: 0000000000000000(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f604a5dae38 CR3: 0000000101dac002 CR4: 0000000000170ef0 Call Trace: <TASK> __mptcp_clean_una_wakeup net/mptcp/protocol.c:1055 [inline] mptcp_clean_una_wakeup net/mptcp/protocol.c:1062 [inline] __mptcp_retrans+0x7f/0x7e0 net/mptcp/protocol.c:2615 mptcp_worker+0x434/0x740 net/mptcp/protocol.c:2767 process_one_work+0x1e0/0x560 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x3c7/0x640 kernel/workqueue.c:3416 kthread+0x121/0x170 kernel/kthread.c:388 ret_from_fork+0x44/0x50 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 </TASK> When fallback to TCP happens early on a client socket, snd_nxt is not yet initialized and any incoming ack will copy such value into snd_una. If the mptcp worker (dumbly) tries mptcp-level re-injection after such ack, that would unconditionally trigger a send buffer cleanup using 'bad' snd_una values. We could easily disable re-injection for fallback sockets, but such dumb behavior already helped catching a few subtle issues and a very low to zero impact in practice. Instead address the issue always initializing snd_nxt (and write_seq, for consistency) at connect time. En el kernel de Linux, se resolvió la siguiente vulnerabilidad: mptcp: asegúrese de que snd_nxt se inicialice correctamente al conectar Christoph informó un símbolo que indica un snd_una dañado: ADVERTENCIA: CPU: 1 PID: 38 en net/mptcp/protocol.c:1005 __mptcp_clean_una +0x4b3/0x620 net/mptcp/protocol.c:1005 Módulos vinculados en: CPU: 1 PID: 38 Comm: kworker/1:1 No contaminado 6.9.0-rc1-gbbeac67456c9 #59 Nombre del hardware: PC estándar QEMU (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 01/04/2014 Cola de trabajo: eventos mptcp_worker RIP: 0010:__mptcp_clean_una+0x4b3/0x620 net/mptcp/protocol.c:1005 Código: be 06 01 00 00 bf 06 01 00 00 e8 a8 12 e7 fe e9 00 fe ff ff e8 8e 1a e7 fe 0f b7 ab 3e 02 00 00 e9 d3 fd ff ff e8 7d 1a e7 fe <0f> 0b 4c 8b bb e0 05 00 00 e9 74 fc ff ff e8 6a 1a e7 fe 0f 0b e9 RSP: 0018:ffffc9000013fd48 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff8881029bd280 RCX: ffffffff82382fe4 RDX: 3cbd00 RSI: ffffffff823833c3 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 00000000000000000 R11: fefefefefefefeff R12 : ffff888138ba8000 R13: 0000000000000106 R14: ffff8881029bd908 R15: ffff888126560000 FS: 00000000000000000(0000) GS:ffff88813bd00000(0000) nlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f604a5dae38 CR3: 0000000101dac002 CR4: 0000000000170ef0 Rastreo de llamadas: __mptcp_clean_una_wakeup net/mptcp/protocol.c:1055 [en línea] mptcp_clean_una_wakeup net/mptcp/protocol.c:1062 [en línea] __mptcp_retrans+0x7f/0x7e0 net/mptcp/protocol.c:2615 mptcp_worker+0x434/ 0x740 neto/ mptcp/protocol.c:2767 Process_one_work+0x1e0/0x560 kernel/workqueue.c:3254 Process_scheduled_works kernel/workqueue.c:3335 [en línea] work_thread+0x3c7/0x640 kernel/workqueue.c:3416 kthread+0x121/0x170 kernel/kthread .c:388 ret_from_fork+0x44/0x50 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 Cuando el retorno a TCP ocurre temprano en un socket de cliente , snd_nxt aún no está inicializado y cualquier confirmación entrante copiará dicho valor en snd_una. Si el trabajador mptcp (tontamente) intenta la reinyección a nivel de mptcp después de tal confirmación, eso desencadenaría incondicionalmente una sanitización del búfer de envío utilizando valores snd_una 'incorrectos'. Podríamos desactivar fácilmente la reinyección para los sockets de respaldo, pero un comportamiento tan tonto ya ayudó a detectar algunos problemas sutiles y un impacto de muy bajo a cero en la práctica. • https://git.kernel.org/stable/c/8fd738049ac3d67a937d36577763b47180aae1ad https://git.kernel.org/stable/c/99951b62bf20cec9247f633a3bea898338b9e5b4 https://git.kernel.org/stable/c/dc941fec0719d0471a5902424d6b2a17df233193 https://git.kernel.org/stable/c/39ca83ed73db9edcc6d70c0dc7a73085a4725012 https://git.kernel.org/stable/c/aa0c07c1f20e05b30019bff083ec43665536f06f https://git.kernel.org/stable/c/592f69b41766d366dbb8ff4ef5a67c4396527bbe https://git.kernel.org/stable/c/fb7a0d334894206ae35f023a82cad5a290fd7386 https://lists.debian.org/debian-lts-announce/2024/06/ • CWE-665: Improper Initialization •
CVSS: 6.2EPSS: 0%CPEs: 3EXPL: 0CVE-2024-36888 – workqueue: Fix selection of wake_cpu in kick_pool()
https://notcve.org/view.php?id=CVE-2024-36888
In the Linux kernel, the following vulnerability has been resolved: workqueue: Fix selection of wake_cpu in kick_pool() With cpu_possible_mask=0-63 and cpu_online_mask=0-7 the following kernel oops was observed: smp: Bringing up secondary CPUs ... smp: Brought up 1 node, 8 CPUs Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0000000000000000 TEID: 0000000000000803 [..] Call Trace: arch_vcpu_is_preempted+0x12/0x80 select_idle_sibling+0x42/0x560 select_task_rq_fair+0x29a/0x3b0 try_to_wake_up+0x38e/0x6e0 kick_pool+0xa4/0x198 __queue_work.part.0+0x2bc/0x3a8 call_timer_fn+0x36/0x160 __run_timers+0x1e2/0x328 __run_timer_base+0x5a/0x88 run_timer_softirq+0x40/0x78 __do_softirq+0x118/0x388 irq_exit_rcu+0xc0/0xd8 do_ext_irq+0xae/0x168 ext_int_handler+0xbe/0xf0 psw_idle_exit+0x0/0xc default_idle_call+0x3c/0x110 do_idle+0xd4/0x158 cpu_startup_entry+0x40/0x48 rest_init+0xc6/0xc8 start_kernel+0x3c4/0x5e0 startup_continue+0x3c/0x50 The crash is caused by calling arch_vcpu_is_preempted() for an offline CPU. To avoid this, select the cpu with cpumask_any_and_distribute() to mask __pod_cpumask with cpu_online_mask. In case no cpu is left in the pool, skip the assignment. tj: This doesn't fully fix the bug as CPUs can still go down between picking the target CPU and the wake call. Fixing that likely requires adding cpu_online() test to either the sched or s390 arch code. However, regardless of how that is fixed, workqueue shouldn't be picking a CPU which isn't online as that would result in unpredictable and worse behavior. • https://git.kernel.org/stable/c/8639ecebc9b1796d7074751a350462f5e1c61cd4 https://git.kernel.org/stable/c/c57824d4fe07c2131f8c48687cbd5ee2be60c767 https://git.kernel.org/stable/c/6d559e70b3eb6623935cbe7f94c1912c1099777b https://git.kernel.org/stable/c/57a01eafdcf78f6da34fad9ff075ed5dfdd9f420 • CWE-476: NULL Pointer Dereference •