In the Linux kernel, the following vulnerability has been resolved: f2fs: compress: fix UAF of f2fsinodeinfo in f2fsfreedic The decompressioctx may be released asynchronously after I/O completion. If this file is deleted immediately after read, and the kworker of processing postreadwq has not been executed yet due to high workloads, It is possible that the inode(f2fsinodeinfo) is evicted and freed before it is used f2fsfreedic. The UAF case as below: Thread A Thread B - f2fsdecompressendio - f2fsputdic - queuework add freedic work to postreadwq - dounlink - iput - evict - callrcu This file is deleted after read. Thread C kworker to process postreadwq - rcudobatch - f2fsfreeinode - kmemcachefree inode is freed by rcu - processscheduledworks - f2fslatefreedic - f2fsfreedic - f2fsreleasedecompmem read (dic->inode)->icompressalgorithm This patch store compressalgorithm and sbi in dic to avoid inode UAF. In addition, the previous solution is deprecated in [1] may cause system hang. [1] https://lore.kernel.org/all/c36ab955-c8db-4a8b-a9d0-f07b5f426c3f@kernel.org