nvd-json-data-feeds/CVE-2024/CVE-2024-270xx/CVE-2024-27031.json

{
  "id": "CVE-2024-27031",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2024-05-01T13:15:49.180",
  "lastModified": "2024-05-01T19:50:25.633",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFS: Fix nfs_netfs_issue_read() xarray locking for writeback interrupt\n\nThe loop inside nfs_netfs_issue_read() currently does not disable\ninterrupts while iterating through pages in the xarray to submit\nfor NFS read.  This is not safe though since after taking xa_lock,\nanother page in the mapping could be processed for writeback inside\nan interrupt, and deadlock can occur.  The fix is simple and clean\nif we use xa_for_each_range(), which handles the iteration with RCU\nwhile reducing code complexity.\n\nThe problem is easily reproduced with the following test:\n mount -o vers=3,fsc 127.0.0.1:/export /mnt/nfs\n dd if=/dev/zero of=/mnt/nfs/file1.bin bs=4096 count=1\n echo 3 > /proc/sys/vm/drop_caches\n dd if=/mnt/nfs/file1.bin of=/dev/null\n umount /mnt/nfs\n\nOn the console with a lockdep-enabled kernel a message similar to\nthe following will be seen:\n\n ================================\n WARNING: inconsistent lock state\n 6.7.0-lockdbg+ #10 Not tainted\n --------------------------------\n inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.\n test5/1708 [HC0[0]:SC0[0]:HE1:SE1] takes:\n ffff888127baa598 (&xa->xa_lock#4){+.?.}-{3:3}, at:\nnfs_netfs_issue_read+0x1b2/0x4b0 [nfs]\n {IN-SOFTIRQ-W} state was registered at:\n   lock_acquire+0x144/0x380\n   _raw_spin_lock_irqsave+0x4e/0xa0\n   __folio_end_writeback+0x17e/0x5c0\n   folio_end_writeback+0x93/0x1b0\n   iomap_finish_ioend+0xeb/0x6a0\n   blk_update_request+0x204/0x7f0\n   blk_mq_end_request+0x30/0x1c0\n   blk_complete_reqs+0x7e/0xa0\n   __do_softirq+0x113/0x544\n   __irq_exit_rcu+0xfe/0x120\n   irq_exit_rcu+0xe/0x20\n   sysvec_call_function_single+0x6f/0x90\n   asm_sysvec_call_function_single+0x1a/0x20\n   pv_native_safe_halt+0xf/0x20\n   default_idle+0x9/0x20\n   default_idle_call+0x67/0xa0\n   do_idle+0x2b5/0x300\n   cpu_startup_entry+0x34/0x40\n   start_secondary+0x19d/0x1c0\n   secondary_startup_64_no_verify+0x18f/0x19b\n irq event stamp: 176891\n hardirqs last  enabled at (176891): [<ffffffffa67a0be4>]\n_raw_spin_unlock_irqrestore+0x44/0x60\n hardirqs last disabled at (176890): [<ffffffffa67a0899>]\n_raw_spin_lock_irqsave+0x79/0xa0\n softirqs last  enabled at (176646): [<ffffffffa515d91e>]\n__irq_exit_rcu+0xfe/0x120\n softirqs last disabled at (176633): [<ffffffffa515d91e>]\n__irq_exit_rcu+0xfe/0x120\n\n other info that might help us debug this:\n  Possible unsafe locking scenario:\n\n        CPU0\n        ----\n   lock(&xa->xa_lock#4);\n   <Interrupt>\n     lock(&xa->xa_lock#4);\n\n  *** DEADLOCK ***\n\n 2 locks held by test5/1708:\n  #0: ffff888127baa498 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at:\n      nfs_start_io_read+0x28/0x90 [nfs]\n  #1: ffff888127baa650 (mapping.invalidate_lock#3){.+.+}-{4:4}, at:\n      page_cache_ra_unbounded+0xa4/0x280\n\n stack backtrace:\n CPU: 6 PID: 1708 Comm: test5 Kdump: loaded Not tainted 6.7.0-lockdbg+\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39\n04/01/2014\n Call Trace:\n  dump_stack_lvl+0x5b/0x90\n  mark_lock+0xb3f/0xd20\n  __lock_acquire+0x77b/0x3360\n  _raw_spin_lock+0x34/0x80\n  nfs_netfs_issue_read+0x1b2/0x4b0 [nfs]\n  netfs_begin_read+0x77f/0x980 [netfs]\n  nfs_netfs_readahead+0x45/0x60 [nfs]\n  nfs_readahead+0x323/0x5a0 [nfs]\n  read_pages+0xf3/0x5c0\n  page_cache_ra_unbounded+0x1c8/0x280\n  filemap_get_pages+0x38c/0xae0\n  filemap_read+0x206/0x5e0\n  nfs_file_read+0xb7/0x140 [nfs]\n  vfs_read+0x2a9/0x460\n  ksys_read+0xb7/0x140"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: NFS: corrige el bloqueo de matriz x de nfs_netfs_issue_read() para interrupci\u00f3n de escritura regresiva. El bucle dentro de nfs_netfs_issue_read() actualmente no deshabilita las interrupciones mientras se itera a trav\u00e9s de p\u00e1ginas en la matriz x para enviarlas a lectura NFS. Sin embargo, esto no es seguro ya que despu\u00e9s de tomar xa_lock, otra p\u00e1gina en el mapeo podr\u00eda procesarse para reescritura dentro de una interrupci\u00f3n, y puede ocurrir un punto muerto. La soluci\u00f3n es simple y limpia si usamos xa_for_each_range(), que maneja la iteraci\u00f3n con RCU mientras reduce la complejidad del c\u00f3digo. El problema se reproduce f\u00e1cilmente con la siguiente prueba: mount -o vers=3,fsc 127.0.0.1:/export /mnt/nfs dd if=/dev/zero of=/mnt/nfs/file1.bin bs=4096 count= 1 echo 3 &gt; /proc/sys/vm/drop_caches dd if=/mnt/nfs/file1.bin of=/dev/null umount /mnt/nfs En la consola con un kernel habilitado para lockdep aparecer\u00e1 un mensaje similar al siguiente ser visto: ================================ ADVERTENCIA: estado de bloqueo inconsistente 6.7.0-lockdbg+ #10 No contaminado - ------------------------------- Uso inconsistente de {IN-SOFTIRQ-W} -&gt; {SOFTIRQ-ON-W}. test5/1708 [HC0[0]:SC0[0]:HE1:SE1] toma: ffff888127baa598 (&amp;xa-&gt;xa_lock#4){+.?.}-{3:3}, en: nfs_netfs_issue_read+0x1b2/0x4b0 [ nfs] El estado {IN-SOFTIRQ-W} se registr\u00f3 en: lock_acquire+0x144/0x380 _raw_spin_lock_irqsave+0x4e/0xa0 __folio_end_writeback+0x17e/0x5c0 folio_end_writeback+0x93/0x1b0 iomap_finish_ioend+0xeb/0x6a0 blk_update_request+ 0x204/0x7f0 blk_mq_end_request+0x30/0x1c0 blk_complete_reqs +0x7e/0xa0 __do_softirq+0x113/0x544 __irq_exit_rcu+0xfe/0x120 irq_exit_rcu+0xe/0x20 sysvec_call_function_single+0x6f/0x90 asm_sysvec_call_function_single+0x1a/0x20 +0xf/0x20 default_idle+0x9/0x20 default_idle_call+0x67/0xa0 do_idle+0x2b5/0x300 cpu_startup_entry +0x34/0x40 start_secondary+0x19d/0x1c0 second_startup_64_no_verify+0x18f/0x19b sello de evento irq: 176891 hardirqs habilitado por \u00faltima vez en (176891): [] _raw_spin_unlock_irqrestore+0x44/0x60 hardirqs deshabilitado por \u00faltima vez en ( 176890): [] _raw_spin_lock_irqsave+0x79/0xa0 softirqs habilitado por \u00faltima vez en (176646): [] __irq_exit_rcu+0xfe/0x120 softirqs deshabilitado por \u00faltima vez en (176633): [] __irq_exit_rcu+0xfe/0x120 Otra informaci\u00f3n que podr\u00eda ayudarnos a depurar esto: Posible escenario de bloqueo inseguro: CPU0 ---- lock(&amp;xa-&gt;xa_lock#4);  bloqueo(&amp;xa-&gt;xa_lock#4); *** DEADLOCK *** 2 bloqueos mantenidos por test5/1708: #0: ffff888127baa498 (&amp;sb-&gt;s_type-&gt;i_mutex_key#22){++++}-{4:4}, en: nfs_start_io_read+0x28/0x90 [nfs] #1: ffff888127baa650 (mapping.invalidate_lock#3){.+.+}-{4:4}, en: page_cache_ra_unbounded+0xa4/0x280 seguimiento de pila: CPU: 6 PID: 1708 Comm: test5 Kdump: cargado No tainted 6.7.0-lockdbg+ Nombre del hardware: PC est\u00e1ndar QEMU (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39 01/04/2014 Seguimiento de llamadas: dump_stack_lvl+0x5b/0x90 mark_lock+0xb3f/0xd20 __lock_acquire+0x77b/ 0x3360 _raw_spin_lock+0x34/0x80 nfs_netfs_issue_read+0x1b2/0x4b0 [nfs] netfs_begin_read+0x77f/0x980 [netfs] nfs_netfs_readahead+0x45/0x60 [nfs_readahead+0x323/0x5 a0 [nfs] read_pages+0xf3/0x5c0 page_cache_ra_unbounded+0x1c8/0x280 filemap_get_pages+ 0x38c/0xae0 filemap_read+0x206/0x5e0 nfs_file_read+0xb7/0x140 [nfs] vfs_read+0x2a9/0x460 ksys_read+0xb7/0x140"
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/8a2e5977cecd3cde6a0e3e86b7b914d00240e5dc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8df1678c021ffeb20ef8a203bd9413f3ed9b0e9a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ad27382f8495f8ef6d2c66c413d756bfd13c0598",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fd5860ab6341506004219b080aea40213b299d2e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}