Liu Shixin 2cab8db145 hfs: fix missing hfs_bnode_get() in __hfs_bnode_create ... commit a9dc087fd3 upstream. Syzbot found a kernel BUG in hfs_bnode_put(): kernel BUG at fs/hfs/bnode.c:466! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 3634 Comm: kworker/u4:5 Not tainted 6.1.0-rc7-syzkaller-00190-g97ee9d1c1696 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:hfs_bnode_put+0x46f/0x480 fs/hfs/bnode.c:466 Code: 8a 80 ff e9 73 fe ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c a0 fe ff ff 48 89 df e8 db 8a 80 ff e9 93 fe ff ff e8 a1 68 2c ff <0f> 0b e8 9a 68 2c ff 0f 0b 0f 1f 84 00 00 00 00 00 55 41 57 41 56 RSP: 0018:ffffc90003b4f258 EFLAGS: 00010293 RAX: ffffffff825e318f RBX: 0000000000000000 RCX: ffff8880739dd7c0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003b4f430 R08: ffffffff825e2d9b R09: ffffed10045157d1 R10: ffffed10045157d1 R11: 1ffff110045157d0 R12: ffff8880228abe80 R13: ffff88807016c000 R14: dffffc0000000000 R15: ffff8880228abe00 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa6ebe88718 CR3: 000000001e93d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> hfs_write_inode+0x1bc/0xb40 write_inode fs/fs-writeback.c:1440 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1652 writeback_sb_inodes+0xb3b/0x18f0 fs/fs-writeback.c:1878 __writeback_inodes_wb+0x125/0x420 fs/fs-writeback.c:1949 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2054 wb_check_start_all fs/fs-writeback.c:2176 [inline] wb_do_writeback fs/fs-writeback.c:2202 [inline] wb_workfn+0x827/0xef0 fs/fs-writeback.c:2235 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 </TASK> The BUG_ON() is triggered at here: /* Dispose of resources used by a node */ void hfs_bnode_put(struct hfs_bnode *node) { if (node) { <skipped> BUG_ON(!atomic_read(&node->refcnt)); <- we have issue here!!!! <skipped> } } By tracing the refcnt, I found the node is created by hfs_bmap_alloc() with refcnt 1. Then the node is used by hfs_btree_write(). There is a missing of hfs_bnode_get() after find the node. The issue happened in following path: <alloc> hfs_bmap_alloc hfs_bnode_find __hfs_bnode_create <- allocate a new node with refcnt 1. hfs_bnode_put <- decrease the refcnt <write> hfs_btree_write hfs_bnode_find __hfs_bnode_create hfs_bnode_findhash <- find the node without refcnt increased. hfs_bnode_put <- trigger the BUG_ON() since refcnt is 0. Link: https://lkml.kernel.org/r/20221212021627.3766829-1-liushixin2@huawei.com Reported-by: syzbot+5b04b49a7ec7226c7426@syzkaller.appspotmail.com Signed-off-by: Liu Shixin <liushixin2@huawei.com> Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com> Cc: Viacheslav Dubeyko <slava@dubeyko.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-03-10 09:39:57 +01:00
..
attr.c	acl: handle idmapped mounts	2021-01-24 14:27:17 +01:00
bfind.c	hfs: add lock nesting notation to hfs_find_init	2021-07-15 10:13:49 -07:00
bitmap.c
bnode.c	hfs: fix missing hfs_bnode_get() in __hfs_bnode_create	2023-03-10 09:39:57 +01:00
brec.c	hfs: fix BUG on bnode parent update	2018-10-31 08:54:13 -07:00
btree.c	hfs: do not free node before using	2018-11-30 14:56:14 -08:00
btree.h	hfs: add lock nesting notation to hfs_find_init	2021-07-15 10:13:49 -07:00
catalog.c	hfs: prevent btree data loss on ENOSPC	2018-10-31 08:54:13 -07:00
dir.c	fs: make helpers idmap mount aware	2021-01-24 14:27:20 +01:00
extent.c	fs/hfs/extent.c: fix array out of bounds read of array extent	2018-10-31 08:54:13 -07:00
hfs_fs.h	fs: make helpers idmap mount aware	2021-01-24 14:27:20 +01:00
hfs.h
inode.c	hfs/hfsplus: avoid WARN_ON() for sanity check, use proper error handling	2023-01-12 11:59:19 +01:00
Kconfig	docs: filesystems: fix renamed references	2020-04-20 15:45:22 -06:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
mdb.c	hfs: stop using ioctl_by_bdev	2020-05-09 16:15:13 -06:00
part_tbl.c
string.c	get rid of 'parent' argument of ->d_compare()	2016-07-31 16:37:25 -04:00
super.c	hfs: add missing clean-up in hfs_fill_super	2021-07-15 10:13:49 -07:00
sysdep.c
trans.c	hfs: Fix OOB Write in hfs_asc2mac	2022-12-31 13:14:05 +01:00