IPVS: ftp: loaded support on port[0] = 21
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BUG: KASAN: use-after-free in dbJoin+0x1ee/0x200 fs/jfs/jfs_dmap.c:2849
Read of size 1 at addr ffff8881a91f7a4c by task jfsCommit/1963

CPU: 1 PID: 1963 Comm: jfsCommit Not tainted 4.14.294-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load1_noabort+0x68/0x70 mm/kasan/report.c:427
 dbJoin+0x1ee/0x200 fs/jfs/jfs_dmap.c:2849
 dbFreeBits+0xd4/0x660 fs/jfs/jfs_dmap.c:2386
 dbFreeDmap+0x61/0x180 fs/jfs/jfs_dmap.c:2135
 dbFree+0x20c/0x4b0 fs/jfs/jfs_dmap.c:392
 txFreeMap+0x691/0xa00 fs/jfs/jfs_txnmgr.c:2579
 txUpdateMap+0x2e3/0xe30 fs/jfs/jfs_txnmgr.c:2375
 txLazyCommit fs/jfs/jfs_txnmgr.c:2709 [inline]
 jfs_lazycommit+0x48b/0x8c0 fs/jfs/jfs_txnmgr.c:2777
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

The buggy address belongs to the page:
page:ffffea0006a47dc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x57ff00000000000()
raw: 057ff00000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: ffffea0006a47de0 ffffea0006a47de0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881a91f7900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881a91f7980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881a91f7a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff8881a91f7a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881a91f7b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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