CVE-2021-46958 (GCVE-0-2021-46958)

Vulnerability from cvelistv5 – Published: 2024-02-27 18:46 – Updated: 2026-08-05 08:45
VLAI
Title
btrfs: fix race between transaction aborts and fsyncs leading to use-after-free
Summary
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix race between transaction aborts and fsyncs leading to use-after-free There is a race between a task aborting a transaction during a commit, a task doing an fsync and the transaction kthread, which leads to an use-after-free of the log root tree. When this happens, it results in a stack trace like the following: BTRFS info (device dm-0): forced readonly BTRFS warning (device dm-0): Skipping commit of aborted transaction. BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5) BTRFS warning (device dm-0): Skipping commit of aborted transaction. BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10 BTRFS error (device dm-0): error writing primary super block to device 1 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10 BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers) BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 RIP: 0010:__mutex_lock+0x139/0xa40 Code: c0 74 19 (...) RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202 RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002 RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000 R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040 R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358 FS: 00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? __btrfs_handle_fs_error+0xde/0x146 [btrfs] ? btrfs_sync_log+0x7c1/0xf20 [btrfs] ? btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_file+0x40c/0x580 [btrfs] do_fsync+0x38/0x70 __x64_sys_fsync+0x10/0x20 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa9142a55c3 Code: 8b 15 09 (...) RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3 RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340 R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0 Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...) ---[ end trace ee2f1b19327d791d ]--- The steps that lead to this crash are the following: 1) We are at transaction N; 2) We have two tasks with a transaction handle attached to transaction N. Task A and Task B. Task B is doing an fsync; 3) Task B is at btrfs_sync_log(), and has saved fs_info->log_root_tree into a local variable named 'log_root_tree' at the top of btrfs_sync_log(). Task B is about to call write_all_supers(), but before that... 4) Task A calls btrfs_commit_transaction(), and after it sets the transaction state to TRANS_STATE_COMMIT_START, an error happens before it w ---truncated---
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-08-15 19:27 UTC
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6843 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ef67963dac255b293e19815ea3d440567be4626f , < a4794be7b00b7eda4b45fffd283ab7d76df7e5d6 (git)
Affected: ef67963dac255b293e19815ea3d440567be4626f , < 633f7f216663587f17601eaa1cf2ac3d5654874c (git)
Affected: ef67963dac255b293e19815ea3d440567be4626f , < e2da98788369bfba1138bada72765c47989a4338 (git)
Affected: ef67963dac255b293e19815ea3d440567be4626f , < 061dde8245356d8864d29e25207aa4daa0be4d3c (git)
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Linux Linux Affected: 5.7
Unaffected: 0 , < 5.7 (semver)
Unaffected: 5.10.36 , ≤ 5.10.* (semver)
Unaffected: 5.11.20 , ≤ 5.11.* (semver)
Unaffected: 5.12.3 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix race between transaction aborts and fsyncs leading to use-after-free\n\nThere is a race between a task aborting a transaction during a commit,\na task doing an fsync and the transaction kthread, which leads to an\nuse-after-free of the log root tree. When this happens, it results in a\nstack trace like the following:\n\n  BTRFS info (device dm-0): forced readonly\n  BTRFS warning (device dm-0): Skipping commit of aborted transaction.\n  BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure\n  BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5)\n  BTRFS warning (device dm-0): Skipping commit of aborted transaction.\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10\n  BTRFS error (device dm-0): error writing primary super block to device 1\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10\n  BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers)\n  BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure\n  general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI\n  CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014\n  RIP: 0010:__mutex_lock+0x139/0xa40\n  Code: c0 74 19 (...)\n  RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202\n  RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002\n  RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000\n  RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000\n  R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040\n  R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358\n  FS:  00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0\n  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n  Call Trace:\n   ? __btrfs_handle_fs_error+0xde/0x146 [btrfs]\n   ? btrfs_sync_log+0x7c1/0xf20 [btrfs]\n   ? btrfs_sync_log+0x7c1/0xf20 [btrfs]\n   btrfs_sync_log+0x7c1/0xf20 [btrfs]\n   btrfs_sync_file+0x40c/0x580 [btrfs]\n   do_fsync+0x38/0x70\n   __x64_sys_fsync+0x10/0x20\n   do_syscall_64+0x33/0x80\n   entry_SYSCALL_64_after_hwframe+0x44/0xae\n  RIP: 0033:0x7fa9142a55c3\n  Code: 8b 15 09 (...)\n  RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a\n  RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3\n  RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005\n  RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c\n  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340\n  R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0\n  Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...)\n  ---[ end trace ee2f1b19327d791d ]---\n\nThe steps that lead to this crash are the following:\n\n1) We are at transaction N;\n\n2) We have two tasks with a transaction handle attached to transaction N.\n   Task A and Task B. Task B is doing an fsync;\n\n3) Task B is at btrfs_sync_log(), and has saved fs_info-\u003elog_root_tree\n   into a local variable named \u0027log_root_tree\u0027 at the top of\n   btrfs_sync_log(). Task B is about to call write_all_supers(), but\n   before that...\n\n4) Task A calls btrfs_commit_transaction(), and after it sets the\n   transaction state to TRANS_STATE_COMMIT_START, an error happens before\n   it w\n---truncated---"
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: btrfs: corrige la ejecuci\u00f3n entre transacciones abortadas y fsyncs que conducen a use-after-free. Hay una carrera entre una tarea que aborta una transacci\u00f3n durante un commit, una tarea que realiza una fsync y la transacci\u00f3n. kthread, lo que conduce a un use-after-free del \u00e1rbol ra\u00edz del registro. Cuando esto sucede, se genera un seguimiento de pila como el siguiente: Informaci\u00f3n BTRFS (dispositivo dm-0): solo lectura forzada Advertencia BTRFS (dispositivo dm-0): omitir confirmaci\u00f3n de transacci\u00f3n abortada. BTRFS: error (dispositivo dm-0) en cleanup_transaction:1958: errno=-5 falla de IO Advertencia de BTRFS (dispositivo dm-0): escritura de p\u00e1gina perdida debido a un error de IO en /dev/mapper/error-test (-5) BTRFS Advertencia (dispositivo dm-0): omitir confirmaci\u00f3n de transacci\u00f3n abortada. Advertencia BTRFS (dispositivo dm-0): IO directa fall\u00f3 en 261 rw 0,0 sector 0xa4e8 len 4096 err no 10 Error BTRFS (dispositivo dm-0): error al escribir el superbloque primario en el dispositivo 1 Advertencia BTRFS (dispositivo dm-0) : error de IO directo ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10 advertencia BTRFS (dispositivo dm-0): error de IO directo ino 261 rw 0,0 sector 0x12e008 len 4096 error no 10 advertencia BTRFS (dispositivo dm-0) : error de IO directo ino 261 rw 0,0 sector 0x12e010 len 4096 error no 10 BTRFS: error (dispositivo dm-0) en write_all_supers:4110: errno=-5 error de IO (1 error al escribir supers) BTRFS: error (dispositivo dm -0) en btrfs_sync_log:3308: errno=-5 Fallo de E/S Fallo de protecci\u00f3n general, probablemente para la direcci\u00f3n no can\u00f3nica 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0- rc5-btrfs-next-84 #1 Nombre del hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 01/04/2014 RIP: 0010:__mutex_lock+ 0x139/0xa40 C\u00f3digo: c0 74 19 (...) RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202 RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 00000000000000002 RD X: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff9f18830d7bc0 R08: 00000000000000000 R09: 0000000000000000 R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040 R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358 FS: 00007fa9140c2b 80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa913d52000 CR3: 000000013d2 b4003 CR4 : 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 00000000000000000 DR6: 00000000fffe0ff0 DR7: 000000 0000000400 Rastreo de llamadas: ? __btrfs_handle_fs_error+0xde/0x146 [btrfs] ? btrfs_sync_log+0x7c1/0xf20 [btrfs]? btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_file+0x40c/0x580 [btrfs] do_fsync+0x38/0x70 __x64_sys_fsync+0x10/0x20 do_syscall_64+ 0x33/0x80 Entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa9142a55c3 C\u00f3digo : 8b 15 09 (...) RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c 3 RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000001 R09: 00007fff26278d5c R10: 0 000000000000000 R11: 0000000000000246 R12: 0000000000000340 R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0 M\u00f3dulos vinculados en: btrfs dm_zero dm_snapshot dm _thin_pool (...) ---[ end trace ee2f1b19327d791d ]--- Los pasos que conducen a este bloqueo son los siguientes: 1) Estamos en la transacci\u00f3n N; 2) Tenemos dos tareas con un identificador de transacci\u00f3n adjunto a la transacci\u00f3n N. Tarea A y Tarea B. La tarea B est\u00e1 realizando una sincronizaci\u00f3n f; 3) La tarea B est\u00e1 en btrfs_sync_log() y ha guardado fs_info-\u0026gt;log_root_tree en una variable local llamada \u0027log_root_tree\u0027 en la parte superior de btrfs_sync_log().---truncado---"
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            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix race between transaction aborts and fsyncs leading to use-after-free\n\nThere is a race between a task aborting a transaction during a commit,\na task doing an fsync and the transaction kthread, which leads to an\nuse-after-free of the log root tree. When this happens, it results in a\nstack trace like the following:\n\n  BTRFS info (device dm-0): forced readonly\n  BTRFS warning (device dm-0): Skipping commit of aborted transaction.\n  BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure\n  BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5)\n  BTRFS warning (device dm-0): Skipping commit of aborted transaction.\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10\n  BTRFS error (device dm-0): error writing primary super block to device 1\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10\n  BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10\n  BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers)\n  BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure\n  general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI\n  CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014\n  RIP: 0010:__mutex_lock+0x139/0xa40\n  Code: c0 74 19 (...)\n  RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202\n  RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002\n  RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000\n  RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000\n  R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040\n  R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358\n  FS:  00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0\n  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n  Call Trace:\n   ? __btrfs_handle_fs_error+0xde/0x146 [btrfs]\n   ? btrfs_sync_log+0x7c1/0xf20 [btrfs]\n   ? btrfs_sync_log+0x7c1/0xf20 [btrfs]\n   btrfs_sync_log+0x7c1/0xf20 [btrfs]\n   btrfs_sync_file+0x40c/0x580 [btrfs]\n   do_fsync+0x38/0x70\n   __x64_sys_fsync+0x10/0x20\n   do_syscall_64+0x33/0x80\n   entry_SYSCALL_64_after_hwframe+0x44/0xae\n  RIP: 0033:0x7fa9142a55c3\n  Code: 8b 15 09 (...)\n  RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a\n  RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3\n  RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005\n  RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c\n  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340\n  R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0\n  Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...)\n  ---[ end trace ee2f1b19327d791d ]---\n\nThe steps that lead to this crash are the following:\n\n1) We are at transaction N;\n\n2) We have two tasks with a transaction handle attached to transaction N.\n   Task A and Task B. Task B is doing an fsync;\n\n3) Task B is at btrfs_sync_log(), and has saved fs_info-\u003elog_root_tree\n   into a local variable named \u0027log_root_tree\u0027 at the top of\n   btrfs_sync_log(). Task B is about to call write_all_supers(), but\n   before that...\n\n4) Task A calls btrfs_commit_transaction(), and after it sets the\n   transaction state to TRANS_STATE_COMMIT_START, an error happens before\n   it w\n---truncated---"
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "scenarios": [
                {
                  "lang": "en",
                  "value": "AV:L - The vulnerable path is reached through local fsync/fdatasync on a mounted btrfs filesystem (fsync \u2192 btrfs_sync_file \u2192 btrfs_sync_log), not via network packet processing or physical device attachment.\nAC:L - An attacker controls both sides of the race by running concurrent threads that induce a transaction abort (many unprivileged write/create/unlink/ENOSPC abort sites) while another thread calls fsync, and can retry indefinitely until the kthread frees log_root_tree under the racing fsync.\nPR:L - Any unprivileged local user with access to a file on a mounted btrfs volume can call fsync and perform ordinary file operations that abort transactions; no capabilities or init-namespace root are required.\nUI:N - btrfs is commonly already mounted (desktops, NAS, Android, containers); the attacker drives writes and fsync from their own processes with no victim mount or open required.\nS:U - The use-after-free corrupts kernel heap state within the same OS/kernel security authority; there is no VM escape, IOMMU bypass, or sandbox boundary crossing.\nC:H - The race frees the log_root_tree (struct btrfs_root) while btrfs_sync_log still holds and later dereferences that pointer (mutex_lock on log_mutex), which after slab reclaim/heap spray enables arbitrary kernel memory reads.\nI:H - Use-after-free of a kernel object with subsequent mutex and list operations on attacker-influenced freed memory yields write and control-flow hijack primitives suitable for privilege escalation.\nA:H - The demonstrated impact is a general protection fault / kernel oops in __mutex_lock via the freed log_root_tree pointer during fsync, which is a full host availability failure."
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-08-05T08:45:13.853Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/a4794be7b00b7eda4b45fffd283ab7d76df7e5d6"
            },
            {
              "url": "https://git.kernel.org/stable/c/633f7f216663587f17601eaa1cf2ac3d5654874c"
            },
            {
              "url": "https://git.kernel.org/stable/c/e2da98788369bfba1138bada72765c47989a4338"
            },
            {
              "url": "https://git.kernel.org/stable/c/061dde8245356d8864d29e25207aa4daa0be4d3c"
            }
          ],
          "title": "btrfs: fix race between transaction aborts and fsyncs leading to use-after-free",
          "x_generator": {
            "engine": "bippy-1.2.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2021-46958",
        "datePublished": "2024-02-27T18:46:59.315Z",
        "dateReserved": "2024-02-27T18:42:55.939Z",
        "dateUpdated": "2026-08-05T08:45:13.853Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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