Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

dm-pcache: reject a kset that overruns its segment

cache_replay(), the writeback worker and the GC worker read a kset of get_kset_onmedia_size() bytes and advance the position by it. A forged key_num makes that size exceed the segment's remaining space, so the advance walks past the segment and trips the cache_pos_advance() BUG_ON.

Reject a kset whose on-media size exceeds cache_seg_remain() before use.