CVE-2024-36966

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: erofs: distingue de manera confiable el modo basado en bloques y el modo fscache cuando se llama a erofs_kill_sb() en el modo basado en desarrollo de bloques, es posible que s_bdev aún no se haya inicializado y, si CONFIG_EROFS_FS_ONDEMAND está habilitado, se confundido con el modo fscache y luego intenta liberar un anon_dev que nunca ha sido asignado, lo que genera la siguiente advertencia: ============================= ================= ida_free solicitó id=0 que no está asignado. ADVERTENCIA: CPU: 14 PID: 926 en lib/idr.c:525 ida_free+0x134/0x140 Módulos vinculados en: CPU: 14 PID: 926 Comm: mount No contaminado 6.9.0-rc3-dirty #630 RIP: 0010:ida_free +0x134/0x140 Seguimiento de llamadas: erofs_kill_sb+0x81/0x90 desactivar_locked_super+0x35/0x80 get_tree_bdev+0x136/0x1e0 vfs_get_tree+0x2c/0xf0 do_new_mount+0x190/0x2f0 [...] ========== ================================== Ahora, cuando se llama a erofs_kill_sb(), erofs_sb_info debe haberse inicializado, así que use sbi->fsid para distinguir entre los dos modos.

In the Linux kernel, the following vulnerability has been resolved: erofs: reliably distinguish block based and fscache mode When erofs_kill_sb() is called in block dev based mode, s_bdev may not have been initialised yet, and if CONFIG_EROFS_FS_ONDEMAND is enabled, it will be mistaken for fscache mode, and then attempt to free an anon_dev that has never been allocated, triggering the following warning: ============================================ ida_free called for id=0 which is not allocated. WARNING: CPU: 14 PID: 926 at lib/idr.c:525 ida_free+0x134/0x140 Modules linked in: CPU: 14 PID: 926 Comm: mount Not tainted 6.9.0-rc3-dirty #630 RIP: 0010:ida_free+0x134/0x140 Call Trace: <TASK> erofs_kill_sb+0x81/0x90 deactivate_locked_super+0x35/0x80 get_tree_bdev+0x136/0x1e0 vfs_get_tree+0x2c/0xf0 do_new_mount+0x190/0x2f0 [...] ============================================ Now when erofs_kill_sb() is called, erofs_sb_info must have been initialised, so use sbi->fsid to distinguish between the two modes.

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system.