In the Linux kernel, the following vulnerability has been resolved: ext4: fix i_data_sem unlock order in ext4_ind_migrate() Fuzzing reports a possible deadlock in jbd2_log_wait_commit. This issue is triggered when an EXT4_IOC_MIGRATE ioctl is set to require synchronous updates because the file descriptor is opened with O_SYNC. This can lead to the jbd2_journal_stop() function calling jbd2_might_wait_for_commit(), potentially causing a deadlock if the EXT4_IOC_MIGRATE call races with a write(2) system call. This problem only arises when CONFIG_PROVE_LOCKING is enabled. In this case, the jbd2_might_wait_for_commit macro locks jbd2_handle in the jbd2_journal_stop function while i_data_sem is locked. This triggers lockdep because the jbd2_journal_start function might also lock the same jbd2_handle simultaneously. Found by Linux Verification Center (linuxtesting.org) with syzkaller. Rule: add
En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: se corrige el orden de desbloqueo de i_data_sem en ext4_ind_migrate() Fuzzing informa un posible bloqueo en jbd2_log_wait_commit. Este problema se activa cuando se configura un ioctl EXT4_IOC_MIGRATE para requerir actualizaciones sincrónicas porque el descriptor de archivo se abre con O_SYNC. Esto puede provocar que la función jbd2_journal_stop() llame a jbd2_might_wait_for_commit(), lo que puede provocar un bloqueo si la llamada a EXT4_IOC_MIGRATE compite con una llamada del sistema write(2). Este problema solo surge cuando CONFIG_PROVE_LOCKING está habilitado. En este caso, la macro jbd2_might_wait_for_commit bloquea jbd2_handle en la función jbd2_journal_stop mientras i_data_sem está bloqueado. Esto activa lockdep porque la función jbd2_journal_start también podría bloquear el mismo jbd2_handle simultáneamente. Encontrado por Linux Verification Center (linuxtesting.org) con syzkaller. Regla: add
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
| Attack Vector | LOCAL |
|---|---|
| Attack Complexity | HIGH |
| Privileges Required | LOW |
| User Interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality Impact | NONE |
| Integrity Impact | NONE |
| Availability Impact | HIGH |
| Source | Type | Description |
|---|---|---|
| [email protected] | Primary |
en
CWE-667
|
| Vendor | Product | Version | Update | Type |
|---|---|---|---|---|
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd3401e7c40> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd368680080> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36a7c8480> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd2dbc8d940> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd3401e4c40> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd384e18b00> | Operating System |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |