In the Linux kernel, the following vulnerability has been resolved: dm cache metadata: fix memory leak on metadata abort retry When failing to acqui...

In the Linux kernel, the following vulnerability has been resolved: dm cache metadata: fix memory leak on metadata abort retry When failing to acquire the root_lock in dm_cache_metadata_abort because the block_manager is read-only, the temporary block_manager created outside the root_lock is not properly released, causing a memory leak. Reproduce steps: This can be reproduced by reloading a new table while the metadata is read-only. While the second call to dm_cache_metadata_abort is caused by lack of support for table preload in dm-cache, mentioned in commit 9b1cc9f251af ("dm cache: share cache-metadata object across inactive and active DM tables"), it exposes the memory leak in dm_cache_metadata_abort when the function is called multiple times. Specifically, dm-cache fails to sync the new cache object's mode during preresume, creating the reproducer condition. This issue could also occur through concurrent metadata_operation_failed calls due to races in cache mode updates, but the table preload scenario below provides a reliable reproducer. 1. Create a cache device with some faulty trailing metadata blocks dmsetup create cmeta < unreferenced object 0xffff8880080c2010 (size 16): comm "dmsetup", pid 132, jiffies 4294982580 hex dump (first 16 bytes): 00 38 b9 07 80 88 ff ff 6a 6b 6b 6b 6b 6b 6b a5 ... backtrace (crc 3118f31c): kmemleak_alloc+0x28/0x40 __kmalloc_cache_noprof+0x3d9/0x510 dm_block_manager_create+0x51/0x140 dm_cache_metadata_abort+…