CVE-2026-74376 md/raid10: reset read_slot when reusing r10bio for discard

In the Linux kernel, the following vulnerability has been resolved: md/raid10: reset readslot when reusing r10bio for discard putallbios always drops devsi.bio, but it only drops devsi.replbio when r10bio-readslot 0. If discard reuses an r10bio that was previously used for a read, readslot can...