CVE-2023-53151

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> md/raid10: prevent soft lockup while flush writes<br /> <br /> Currently, there is no limit for raid1/raid10 plugged bio. While flushing<br /> writes, raid1 has cond_resched() while raid10 doesn&amp;#39;t, and too many<br /> writes can cause soft lockup.<br /> <br /> Follow up soft lockup can be triggered easily with writeback test for<br /> raid10 with ramdisks:<br /> <br /> watchdog: BUG: soft lockup - CPU#10 stuck for 27s! [md0_raid10:1293]<br /> Call Trace:<br /> <br /> call_rcu+0x16/0x20<br /> put_object+0x41/0x80<br /> __delete_object+0x50/0x90<br /> delete_object_full+0x2b/0x40<br /> kmemleak_free+0x46/0xa0<br /> slab_free_freelist_hook.constprop.0+0xed/0x1a0<br /> kmem_cache_free+0xfd/0x300<br /> mempool_free_slab+0x1f/0x30<br /> mempool_free+0x3a/0x100<br /> bio_free+0x59/0x80<br /> bio_put+0xcf/0x2c0<br /> free_r10bio+0xbf/0xf0<br /> raid_end_bio_io+0x78/0xb0<br /> one_write_done+0x8a/0xa0<br /> raid10_end_write_request+0x1b4/0x430<br /> bio_endio+0x175/0x320<br /> brd_submit_bio+0x3b9/0x9b7 [brd]<br /> __submit_bio+0x69/0xe0<br /> submit_bio_noacct_nocheck+0x1e6/0x5a0<br /> submit_bio_noacct+0x38c/0x7e0<br /> flush_pending_writes+0xf0/0x240<br /> raid10d+0xac/0x1ed0<br /> <br /> Fix the problem by adding cond_resched() to raid10 like what raid1 did.<br /> <br /> Note that unlimited plugged bio still need to be optimized, for example,<br /> in the case of lots of dirty pages writeback, this will take lots of<br /> memory and io will spend a long time in plug, hence io latency is bad.