Описание
In the Linux kernel, the following vulnerability has been resolved:
ext4: don't set SB_RDONLY after filesystem errors
When the filesystem is mounted with errors=remount-ro, we were setting SB_RDONLY flag to stop all filesystem modifications. We knew this misses proper locking (sb->s_umount) and does not go through proper filesystem remount procedure but it has been the way this worked since early ext2 days and it was good enough for catastrophic situation damage mitigation. Recently, syzbot has found a way (see link) to trigger warnings in filesystem freezing because the code got confused by SB_RDONLY changing under its hands. Since these days we set EXT4_FLAGS_SHUTDOWN on the superblock which is enough to stop all filesystem modifications, modifying SB_RDONLY shouldn't be needed. So stop doing that.
In the Linux kernel, the following vulnerability has been resolved:
ext4: don't set SB_RDONLY after filesystem errors
When the filesystem is mounted with errors=remount-ro, we were setting SB_RDONLY flag to stop all filesystem modifications. We knew this misses proper locking (sb->s_umount) and does not go through proper filesystem remount procedure but it has been the way this worked since early ext2 days and it was good enough for catastrophic situation damage mitigation. Recently, syzbot has found a way (see link) to trigger warnings in filesystem freezing because the code got confused by SB_RDONLY changing under its hands. Since these days we set EXT4_FLAGS_SHUTDOWN on the superblock which is enough to stop all filesystem modifications, modifying SB_RDONLY shouldn't be needed. So stop doing that.
Ссылки
- https://nvd.nist.gov/vuln/detail/CVE-2024-50191
- https://git.kernel.org/stable/c/4061e07f040a091f694f461b86a26cf95ae66439
- https://git.kernel.org/stable/c/58c0648e4c773f5b54f0cb63bc8c7c6bf52719a9
- https://git.kernel.org/stable/c/d3476f3dad4ad68ae5f6b008ea6591d1520da5d8
- https://git.kernel.org/stable/c/ee77c388469116565e009eaa704a60bc78489e09
- https://git.kernel.org/stable/c/fbb177bc1d6487cd3e9b50ae0be2781b7297980d
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: ext4: don't set SB_RDONLY after filesystem errors When the filesystem is mounted with errors=remount-ro, we were setting SB_RDONLY flag to stop all filesystem modifications. We knew this misses proper locking (sb->s_umount) and does not go through proper filesystem remount procedure but it has been the way this worked since early ext2 days and it was good enough for catastrophic situation damage mitigation. Recently, syzbot has found a way (see link) to trigger warnings in filesystem freezing because the code got confused by SB_RDONLY changing under its hands. Since these days we set EXT4_FLAGS_SHUTDOWN on the superblock which is enough to stop all filesystem modifications, modifying SB_RDONLY shouldn't be needed. So stop doing that.
In the Linux kernel, the following vulnerability has been resolved: ext4: don't set SB_RDONLY after filesystem errors When the filesystem is mounted with errors=remount-ro, we were setting SB_RDONLY flag to stop all filesystem modifications. We knew this misses proper locking (sb->s_umount) and does not go through proper filesystem remount procedure but it has been the way this worked since early ext2 days and it was good enough for catastrophic situation damage mitigation. Recently, syzbot has found a way (see link) to trigger warnings in filesystem freezing because the code got confused by SB_RDONLY changing under its hands. Since these days we set EXT4_FLAGS_SHUTDOWN on the superblock which is enough to stop all filesystem modifications, modifying SB_RDONLY shouldn't be needed. So stop doing that.
In the Linux kernel, the following vulnerability has been resolved: ext4: don't set SB_RDONLY after filesystem errors When the filesystem is mounted with errors=remount-ro, we were setting SB_RDONLY flag to stop all filesystem modifications. We knew this misses proper locking (sb->s_umount) and does not go through proper filesystem remount procedure but it has been the way this worked since early ext2 days and it was good enough for catastrophic situation damage mitigation. Recently, syzbot has found a way (see link) to trigger warnings in filesystem freezing because the code got confused by SB_RDONLY changing under its hands. Since these days we set EXT4_FLAGS_SHUTDOWN on the superblock which is enough to stop all filesystem modifications, modifying SB_RDONLY shouldn't be needed. So stop doing that.
In the Linux kernel, the following vulnerability has been resolved: e ...
Уязвимость компонента ext4 ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании