Wind River Support Network

Description

In the Linux kernel, the following vulnerability has been resolved:[EOL][EOL]md/raid10: fix null-ptr-deref in raid10_sync_request[EOL][EOL]init_resync() inits mempool and sets conf->have_replacemnt at the beginning[EOL]of sync, close_sync() frees the mempool when sync is completed.[EOL][EOL]After [1] recovery might be skipped and init_resync() is called but[EOL]close_sync() is not. null-ptr-deref occurs with r10bio->dev[i].repl_bio.[EOL][EOL]The following is one way to reproduce the issue.[EOL][EOL]  1) create a array, wait for resync to complete, mddev->recovery_cp is set[EOL]     to MaxSector.[EOL]  2) recovery is woken and it is skipped. conf->have_replacement is set to[EOL]     0 in init_resync(). close_sync() not called.[EOL]  3) some io errors and rdev A is set to WantReplacement.[EOL]  4) a new device is added and set to A's replacement.[EOL]  5) recovery is woken, A have replacement, but conf->have_replacemnt is[EOL]     0. r10bio->dev[i].repl_bio will not be alloced and null-ptr-deref[EOL]     occurs.[EOL][EOL]Fix it by not calling init_resync() if recovery skipped.[EOL][EOL][1] commit 7e83ccbecd60 ("md/raid10: Allow skipping recovery when clean arrays are assembled")