KASAN: slab-use-after-free Read in folio

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KASAN: slab-use-after-free Read in folio_evictable mm				2	383d	446d	0/28	auto-obsoleted due to no activity on 2023/12/05 22:18
upstream	KASAN: slab-use-after-free Read in folio_evictable (2) mm				36	48d	91d	0/28	closed as dup on 2024/06/17 18:12
==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: slab-use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: slab-use-after-free in mapping_unevictable include/linux/pagemap.h:260 [inline]
BUG: KASAN: slab-use-after-free in folio_evictable+0xe3/0x310 mm/internal.h:370
Read of size 8 at addr ffff888020d7e6c0 by task kswapd0/88

CPU: 0 UID: 0 PID: 88 Comm: kswapd0 Not tainted 6.11.0-rc4-syzkaller-00255-gd2bafcf224f3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 mapping_unevictable include/linux/pagemap.h:260 [inline]
 folio_evictable+0xe3/0x310 mm/internal.h:370
 shrink_folio_list+0x90c/0x8c90 mm/vmscan.c:1071
 evict_folios+0x54c7/0x7b60 mm/vmscan.c:4580
 try_to_shrink_lruvec+0x9ab/0xbb0 mm/vmscan.c:4775
 shrink_one+0x3b9/0x850 mm/vmscan.c:4813
 shrink_many mm/vmscan.c:4876 [inline]
 lru_gen_shrink_node mm/vmscan.c:4954 [inline]
 shrink_node+0x3799/0x3de0 mm/vmscan.c:5934
 kswapd_shrink_node mm/vmscan.c:6762 [inline]
 balance_pgdat mm/vmscan.c:6954 [inline]
 kswapd+0x1bcd/0x35a0 mm/vmscan.c:7223
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 27:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3988 [inline]
 slab_alloc_node mm/slub.c:4037 [inline]
 kmem_cache_alloc_lru_noprof+0x139/0x2b0 mm/slub.c:4056
 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4622
 alloc_inode fs/inode.c:263 [inline]
 new_inode_pseudo fs/inode.c:1073 [inline]
 new_inode+0x6e/0x310 fs/inode.c:1092
 __shmem_get_inode mm/shmem.c:2658 [inline]
 shmem_get_inode+0x34a/0xd50 mm/shmem.c:2729
 shmem_mknod+0x5f/0x1e0 mm/shmem.c:3426
 vfs_mknod+0x36d/0x3b0 fs/namei.c:4088
 handle_create drivers/base/devtmpfs.c:219 [inline]
 handle drivers/base/devtmpfs.c:384 [inline]
 devtmpfs_work_loop+0x963/0x1040 drivers/base/devtmpfs.c:399
 devtmpfsd+0x4c/0x50 drivers/base/devtmpfs.c:441
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 25:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2252 [inline]
 slab_free mm/slub.c:4473 [inline]
 kmem_cache_free+0x145/0x350 mm/slub.c:4548
 rcu_do_batch kernel/rcu/tree.c:2569 [inline]
 rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2843
 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
 __call_rcu_common kernel/rcu/tree.c:3106 [inline]
 call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210
 destroy_inode fs/inode.c:318 [inline]
 evict+0x88b/0x950 fs/inode.c:729
 do_unlinkat+0x512/0x830 fs/namei.c:4493
 __do_sys_unlink fs/namei.c:4534 [inline]
 __se_sys_unlink fs/namei.c:4532 [inline]
 __x64_sys_unlink+0x47/0x50 fs/namei.c:4532
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888020d7e1f8
 which belongs to the cache shmem_inode_cache of size 1544
The buggy address is located 1224 bytes inside of
 freed 1544-byte region [ffff888020d7e1f8, ffff888020d7e800)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20d78
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000040 ffff8880172e7140 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000130013 00000001fdffffff 0000000000000000
head: 00fff00000000040 ffff8880172e7140 dead000000000122 0000000000000000
head: 0000000000000000 0000000000130013 00000001fdffffff 0000000000000000
head: 00fff00000000003 ffffea0000835e01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 27, tgid 27 (kdevtmpfs), ts 6763483046, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2321
 allocate_slab+0x5a/0x2f0 mm/slub.c:2484
 new_slab mm/slub.c:2537 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3723
 __slab_alloc+0x58/0xa0 mm/slub.c:3813
 __slab_alloc_node mm/slub.c:3866 [inline]
 slab_alloc_node mm/slub.c:4025 [inline]
 kmem_cache_alloc_lru_noprof+0x1c5/0x2b0 mm/slub.c:4056
 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4622
 alloc_inode fs/inode.c:263 [inline]
 new_inode_pseudo fs/inode.c:1073 [inline]
 new_inode+0x6e/0x310 fs/inode.c:1092
 __shmem_get_inode mm/shmem.c:2658 [inline]
 shmem_get_inode+0x34a/0xd50 mm/shmem.c:2729
 shmem_mknod+0x5f/0x1e0 mm/shmem.c:3426
 vfs_mknod+0x36d/0x3b0 fs/namei.c:4088
 handle_create drivers/base/devtmpfs.c:219 [inline]
 handle drivers/base/devtmpfs.c:384 [inline]
 devtmpfs_work_loop+0x963/0x1040 drivers/base/devtmpfs.c:399
 devtmpfsd+0x4c/0x50 drivers/base/devtmpfs.c:441
 kthread+0x2f0/0x390 kernel/kthread.c:389
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888020d7e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020d7e600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888020d7e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888020d7e700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020d7e780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================