Re: [syzbot] Re: [syzbot] [bcachefs?] KASAN: slab-out-of-bounds Write in bch2_dev_journal_init

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Subject: Re: [syzbot] [bcachefs?] KASAN: slab-out-of-bounds Write in bch2_dev_journal_init
Author: lizhi.xu@xxxxxxxxxxxxx

unsigned may overflow

#syz test: upstream c3f2d783a459

diff --git a/fs/bcachefs/journal_types.h b/fs/bcachefs/journal_types.h
index 19183fcf7ad7..311a62a0f6c1 100644
--- a/fs/bcachefs/journal_types.h
+++ b/fs/bcachefs/journal_types.h
@@ -323,7 +323,7 @@ struct journal_device {
 	unsigned		dirty_idx_ondisk;
 	unsigned		dirty_idx;
 	unsigned		cur_idx;		/* Journal bucket we're currently writing to */
-	unsigned		nr;
+	u64			nr;
 
 	u64			*buckets;