CVE-2024-26773

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()<br /> <br /> Determine if the group block bitmap is corrupted before using ac_b_ex in<br /> ext4_mb_try_best_found() to avoid allocating blocks from a group with a<br /> corrupted block bitmap in the following concurrency and making the<br /> situation worse.<br /> <br /> ext4_mb_regular_allocator<br /> ext4_lock_group(sb, group)<br /> ext4_mb_good_group<br /> // check if the group bbitmap is corrupted<br /> ext4_mb_complex_scan_group<br /> // Scan group gets ac_b_ex but doesn&amp;#39;t use it<br /> ext4_unlock_group(sb, group)<br /> ext4_mark_group_bitmap_corrupted(group)<br /> // The block bitmap was corrupted during<br /> // the group unlock gap.<br /> ext4_mb_try_best_found<br /> ext4_lock_group(ac-&gt;ac_sb, group)<br /> ext4_mb_use_best_found<br /> mb_mark_used<br /> // Allocating blocks in block bitmap corrupted group