KASAN: use-after-free Read in f2fs_release

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	BUG: unable to handle kernel NULL pointer dereference in f2fs_release_folio f2fs				7	378d	500d	0/26	auto-obsoleted due to no activity on 2023/08/17 23:31
==================================================================
BUG: KASAN: use-after-free in F2FS_SB fs/f2fs/f2fs.h:1969 [inline]
BUG: KASAN: use-after-free in F2FS_I_SB fs/f2fs/f2fs.h:1974 [inline]
BUG: KASAN: use-after-free in F2FS_M_SB fs/f2fs/f2fs.h:1979 [inline]
BUG: KASAN: use-after-free in f2fs_release_folio+0x10e/0x450 fs/f2fs/data.c:3759
Read of size 8 at addr ffff88808dc56678 by task kswapd0/110

CPU: 0 PID: 110 Comm: kswapd0 Not tainted 6.1.65-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 F2FS_SB fs/f2fs/f2fs.h:1969 [inline]
 F2FS_I_SB fs/f2fs/f2fs.h:1974 [inline]
 F2FS_M_SB fs/f2fs/f2fs.h:1979 [inline]
 f2fs_release_folio+0x10e/0x450 fs/f2fs/data.c:3759
 shrink_folio_list+0x2872/0x8ee0 mm/vmscan.c:1996
 evict_folios+0xb42/0x2810 mm/vmscan.c:5039
 lru_gen_shrink_lruvec mm/vmscan.c:5223 [inline]
 shrink_lruvec+0xdbf/0x4650 mm/vmscan.c:5918
 </TASK>

Allocated by task 3002:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:955 [inline]
 __kmalloc+0xb2/0x230 mm/slab_common.c:968
 kmalloc include/linux/slab.h:558 [inline]
 tomoyo_realpath_from_path+0xcb/0x5d0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x29f/0x710 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x120 security/security.c:1361
 vfs_getattr+0x26/0x360 fs/stat.c:158
 vfs_statx+0x194/0x4b0 fs/stat.c:233
 vfs_fstatat fs/stat.c:267 [inline]
 __do_sys_newfstatat fs/stat.c:437 [inline]
 __se_sys_newfstatat fs/stat.c:431 [inline]
 __x64_sys_newfstatat+0x151/0x1e0 fs/stat.c:431
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 3002:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 tomoyo_realpath_from_path+0x59f/0x5d0 security/tomoyo/realpath.c:286
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x29f/0x710 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x120 security/security.c:1361
 vfs_getattr+0x26/0x360 fs/stat.c:158
 vfs_statx+0x194/0x4b0 fs/stat.c:233
 vfs_fstatat fs/stat.c:267 [inline]
 __do_sys_newfstatat fs/stat.c:437 [inline]
 __se_sys_newfstatat fs/stat.c:431 [inline]
 __x64_sys_newfstatat+0x151/0x1e0 fs/stat.c:431
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 insert_work+0x54/0x3d0 kernel/workqueue.c:1361
 __queue_work+0xb4b/0xf90 kernel/workqueue.c:1520
 queue_work_on+0x14b/0x250 kernel/workqueue.c:1548
 rcu_do_batch kernel/rcu/tree.c:2264 [inline]
 rcu_core+0xad4/0x17e0 kernel/rcu/tree.c:2524
 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2812
 put_super fs/super.c:311 [inline]
 deactivate_locked_super+0xd4/0x110 fs/super.c:343
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88808dc56000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1656 bytes inside of
 4096-byte region [ffff88808dc56000, ffff88808dc57000)

The buggy address belongs to the physical page:
page:ffffea0002371400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8dc50
head:ffffea0002371400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001fbe800 dead000000000002 ffff888012442140
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4036, tgid 4036 (kworker/1:8), ts 1296678536324, free_ts 1287752096555
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513
 prep_new_page mm/page_alloc.c:2520 [inline]
 get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5545
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc_node_track_caller+0xa0/0x220 mm/slab_common.c:975
 kmalloc_reserve net/core/skbuff.c:446 [inline]
 __alloc_skb+0x135/0x670 net/core/skbuff.c:515
 alloc_skb include/linux/skbuff.h:1276 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x24c/0xa90 drivers/net/netdevsim/dev.c:850
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1440 [inline]
 free_pcp_prepare mm/page_alloc.c:1490 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3358
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3453
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586
 put_cpu_partial+0x17b/0x250 mm/slub.c:2662
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 getname_flags+0xb8/0x4f0 fs/namei.c:139
 vfs_fstatat fs/stat.c:266 [inline]
 __do_sys_newfstatat fs/stat.c:437 [inline]
 __se_sys_newfstatat fs/stat.c:431 [inline]
 __x64_sys_newfstatat+0x130/0x1e0 fs/stat.c:431
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff88808dc56500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808dc56580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88808dc56600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                                ^
 ffff88808dc56680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808dc56700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2023/12/04 08:27	linux-6.1.y	c6114c845984	f819d6f7	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: use-after-free Read in f2fs_release_folio
2023/10/16 06:16	linux-6.1.y	adc4d740ad9e	f757a323	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: use-after-free Read in f2fs_release_folio