CVE-2024-42103

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2024-42103
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix adding block group to a reclaim list and the unused list during reclaim There is a potential parallel list adding for retrying in btrfs_reclaim_bgs_work and adding to the unused list. Since the block group is removed from the reclaim list and it is on a relocation work, it can be added into the unused list in parallel. When that happens, adding it to the reclaim list will corrupt the list head and trigger list corruption like below. Fix it by taking fs_info->unused_bgs_lock. [177.504][T2585409] BTRFS error (device nullb1): error relocating ch= unk 2415919104 [177.514][T2585409] list_del corruption. next->prev should be ff1100= 0344b119c0, but was ff11000377e87c70. (next=3Dff110002390cd9c0) [177.529][T2585409] ------------[ cut here ]------------ [177.537][T2585409] kernel BUG at lib/list_debug.c:65! [177.545][T2585409] Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI [177.555][T2585409] CPU: 9 PID: 2585409 Comm: kworker/u128:2 Tainted: G W 6.10.0-rc5-kts #1 [177.568][T2585409] Hardware name: Supermicro SYS-520P-WTR/X12SPW-TF, BIOS 1.2 02/14/2022 [177.579][T2585409] Workqueue: events_unbound btrfs_reclaim_bgs_work[btrfs] [177.589][T2585409] RIP: 0010:__list_del_entry_valid_or_report.cold+0x70/0x72 [177.624][T2585409] RSP: 0018:ff11000377e87a70 EFLAGS: 00010286 [177.633][T2585409] RAX: 000000000000006d RBX: ff11000344b119c0 RCX:0000000000000000 [177.644][T2585409] RDX: 000000000000006d RSI: 0000000000000008 RDI:ffe21c006efd0f40 [177.655][T2585409] RBP: ff110002e0509f78 R08: 0000000000000001 R09:ffe21c006efd0f08 [177.665][T2585409] R10: ff11000377e87847 R11: 0000000000000000 R12:ff110002390cd9c0 [177.676][T2585409] R13: ff11000344b119c0 R14: ff110002e0508000 R15:dffffc0000000000 [177.687][T2585409] FS: 0000000000000000(0000) GS:ff11000fec880000(0000) knlGS:0000000000000000 [177.700][T2585409] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [177.709][T2585409] CR2: 00007f06bc7b1978 CR3: 0000001021e86005 CR4:0000000000771ef0 [177.720][T2585409] DR0: 0000000000000000 DR1: 0000000000000000 DR2:0000000000000000 [177.731][T2585409] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:0000000000000400 [177.742][T2585409] PKRU: 55555554 [177.748][T2585409] Call Trace: [177.753][T2585409] <TASK> [177.759][T2585409] ? __die_body.cold+0x19/0x27 [177.766][T2585409] ? die+0x2e/0x50 [177.772][T2585409] ? do_trap+0x1ea/0x2d0 [177.779][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.788][T2585409] ? do_error_trap+0xa3/0x160 [177.795][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.805][T2585409] ? handle_invalid_op+0x2c/0x40 [177.812][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.820][T2585409] ? exc_invalid_op+0x2d/0x40 [177.827][T2585409] ? asm_exc_invalid_op+0x1a/0x20 [177.834][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.843][T2585409] btrfs_delete_unused_bgs+0x3d9/0x14c0 [btrfs] There is a similar retry_list code in btrfs_delete_unused_bgs(), but it is safe, AFAICS. Since the block group was in the unused list, the used bytes should be 0 when it was added to the unused list. Then, it checks block_group->{used,reserved,pinned} are still 0 under the block_group->lock. So, they should be still eligible for the unused list, not the reclaim list. The reason it is safe there it's because because we're holding space_info->groups_sem in write mode. That means no other task can allocate from the block group, so while we are at deleted_unused_bgs() it's not possible for other tasks to allocate and deallocate extents from the block group, so it can't be added to the unused list or the reclaim list by anyone else. The bug can be reproduced by btrfs/166 after a few rounds. In practice this can be hit when relocation cannot find more chunk space and ends with ENOSPC.
CVSS

No CVSS.

References
Link Resource
https://git.kernel.org/stable/c/326fa14549d7969ef80d3f5beea5470cd1c8e67f
https://git.kernel.org/stable/c/48f091fd50b2eb33ae5eaea9ed3c4f81603acf38
https://git.kernel.org/stable/c/522b39bd7163e8dc49f8cf10b9b782218ac48746
https://git.kernel.org/stable/c/aa1d8cc0cc500e06b316cd6732d4e6c1388fe33c
https://git.kernel.org/stable/c/f8e960be923f74a273c62478c9cab9523936752b
Configurations

No configuration.

History

30 Jul 2024, 13:32

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: btrfs: corrige la adición de un grupo de bloques a una lista de recuperación y la lista no utilizada durante la recuperación. Existe una posible adición de lista paralela para volver a intentarlo en btrfs_reclaim_bgs_work y agregarla a la lista no utilizada. Dado que el grupo de bloques se elimina de la lista de recuperación y se encuentra en un trabajo de reubicación, se puede agregar a la lista no utilizada en paralelo. Cuando eso sucede, agregarlo a la lista de recuperación dañará el encabezado de la lista y provocará una corrupción en la lista como se muestra a continuación. Solucionarlo tomando fs_info-&gt;unused_bgs_lock. [177.504][T2585409] Error BTRFS (dispositivo nullb1): error al reubicar ch= unk 2415919104 [177.514][T2585409] corrupción list_del. siguiente-&gt;anterior debería ser ff1100= 0344b119c0, pero era ff11000377e87c70. (next=3Dff110002390cd9c0) [177.529][T2585409] ------------[ cortar aquí ]------------ [177.537][T2585409] ERROR del kernel en lib/ list_debug.c:65! [177.545][T2585409] Ups: código de operación no válido: 0000 [#1] PREEMPT SMP KASAN NOPTI [177.555][T2585409] CPU: 9 PID: 2585409 Comm: kworker/u128:2 Contaminado: GW 6.10.0-rc5-kts # 1 [177.568][T2585409] Nombre de hardware: Supermicro SYS-520P-WTR/X12SPW-TF, BIOS 1.2 14/02/2022 [177.579][T2585409] Cola de trabajo: events_unbound btrfs_reclaim_bgs_work[btrfs] [177.589][T2585409] QEPD: 0010 :__list_del_entry_valid_or_report.cold+0x70/0x72 [177.624][T2585409] RSP: 0018:ff11000377e87a70 EFLAGS: 00010286 [177.633][T2585409] RAX: 000000000000006d RBX: ff11000344b119c0 RCX:0000000000000000 [177.644][T2585409] RDX: 000000000000006d RSI: 0000000000000008 RDI :ffe21c006efd0f40 [177.655][T2585409] RBP: ff110002e0509f78 R08: 0000000000000001 R09:ffe21c006efd0f08 [177.665][T2585409] R10: 7847 R11: 0000000000000000 R12:ff110002390cd9c0 [177.676][T2585409] R13: ff11000344b119c0 R14: ff110002e0508000 R15:dffffc0000000000 [177. 687] [T2585409] FS: 0000000000000000(0000) GS:ff11000fec880000(0000) knlGS:0000000000000000 [177.700][T2585409] CS: 0010 DS: 0000 ES: 0000 CR0: 00000080050033 [177.709][T2585409] CR2: 00007f06bc7b1978 CR3: 0000001021e86005 CR4: 0000000000771ef0 [177.720][T2585409] DR0: 0000000000000000 DR1: 0000000000000000 DR2:0000000000000000 [177.731][T2585409] DR3: 00000000 DR6: 00000000fffe0ff0 DR7:0000000000000400 [177.742][T2585409] PKRU: 55555554 [177.748][T2585409] Seguimiento de llamadas: [ 177.753][T2585409] [177.759][T2585409] ? __die_body.cold+0x19/0x27 [177.766][T2585409] ? morir+0x2e/0x50 [177.772][T2585409] ? do_trap+0x1ea/0x2d0 [177.779][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.788][T2585409] ? do_error_trap+0xa3/0x160 [177.795][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.805][T2585409] ? handle_invalid_op+0x2c/0x40 [177.812][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.820][T2585409] ? exc_invalid_op+0x2d/0x40 [177.827][T2585409] ? asm_exc_invalid_op+0x1a/0x20 [177.834][T2585409] ? __list_del_entry_valid_or_report.cold+0x70/0x72 [177.843][T2585409] btrfs_delete_unused_bgs+0x3d9/0x14c0 [btrfs] Hay un código retry_list similar en btrfs_delete_unused_bgs(), pero es seguro, AFAICS. Dado que el grupo de bloques estaba en la lista no utilizada, los bytes usados deberían ser 0 cuando se agregó a la lista no utilizada. Luego, verifica que block_group-&gt;{used,reserved,pinned} todavía sean 0 bajo block_group-&gt;lock. Por lo tanto, aún deberían ser elegibles para la lista no utilizada, no para la lista de recuperación. La razón por la que es seguro allí es porque mantenemos space_info-&gt;groups_sem en modo de escritura. Eso significa que ninguna otra tarea puede asignar desde el grupo de bloques, por lo que mientras estamos en deleted_unused_bgs() no es posible que otras tareas asignen y desasignen extensiones del grupo de bloques, por lo que no se pueden agregar a la lista no utilizada ni a la reclamación. lista por cualquier otra persona. El error puede repro ---truncado---

30 Jul 2024, 08:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-07-30 08:15

Updated : 2024-07-30 13:32

NVD link : CVE-2024-42103

Mitre link : CVE-2024-42103

CVE.ORG link : CVE-2024-42103

JSON object : View

Products Affected

No product.

CWE

No CWE.