================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88807f0e5294 by task jfsCommit/112 CPU: 1 PID: 112 Comm: jfsCommit Not tainted 6.9.0-rc5-syzkaller-00007-g4d2008430ce8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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 jfs_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5368: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace+0x1db/0x360 mm/slub.c:3997 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [inline] jfs_fill_super+0xff/0xc50 fs/jfs/super.c:495 mount_bdev+0x20a/0x2d0 fs/super.c:1658 legacy_get_tree+0xee/0x190 fs/fs_context.c:662 vfs_get_tree+0x90/0x2a0 fs/super.c:1779 do_new_mount+0x2be/0xb40 fs/namespace.c:3352 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5107: 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+0xa6/0xe0 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:2106 [inline] slab_free mm/slub.c:4280 [inline] kfree+0x153/0x3a0 mm/slub.c:4390 generic_shutdown_super+0x136/0x2d0 fs/super.c:641 kill_block_super+0x44/0x90 fs/super.c:1675 deactivate_locked_super+0xc4/0x130 fs/super.c:472 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x24f/0x310 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807f0e5200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88807f0e5200, ffff88807f0e5300) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f0e4 head: order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 00fff80000000840 ffff888015041b40 ffffea000093cf00 0000000000000007 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 head: 00fff80000000840 ffff888015041b40 ffffea000093cf00 0000000000000007 head: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 head: 00fff80000000001 ffffea0001fc3901 dead000000000122 00000000ffffffff head: 0000000200000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5213, tgid 1668570838 (syz-executor.2), ts 5213, free_ts 91835327805 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2175 allocate_slab mm/slub.c:2338 [inline] new_slab+0x84/0x2f0 mm/slub.c:2391 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525 __slab_alloc mm/slub.c:3610 [inline] __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] __do_kmalloc_node mm/slub.c:3965 [inline] __kmalloc+0x2e5/0x4a0 mm/slub.c:3979 kmalloc_array include/linux/slab.h:665 [inline] kcalloc include/linux/slab.h:696 [inline] security_inode_init_security+0x126/0x440 security/security.c:1720 __ext4_new_inode+0x34b4/0x4390 fs/ext4/ialloc.c:1326 ext4_symlink+0x38d/0xb50 fs/ext4/namei.c:3395 vfs_symlink+0x137/0x2a0 fs/namei.c:4481 do_symlinkat+0x222/0x3a0 fs/namei.c:4507 __do_sys_symlinkat fs/namei.c:4523 [inline] __se_sys_symlinkat fs/namei.c:4520 [inline] __x64_sys_symlinkat+0x99/0xb0 fs/namei.c:4520 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 4525 tgid 4525 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x97b/0xaa0 mm/page_alloc.c:2347 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487 __slab_free+0x31b/0x3d0 mm/slub.c:4192 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x5e/0xc0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmalloc_trace+0x16f/0x360 mm/slub.c:3992 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [inline] kernfs_fop_open+0x3e0/0xd10 fs/kernfs/file.c:623 do_dentry_open+0x907/0x15a0 fs/open.c:955 do_open fs/namei.c:3642 [inline] path_openat+0x2860/0x3240 fs/namei.c:3799 do_filp_open+0x235/0x490 fs/namei.c:3826 do_sys_openat2+0x13e/0x1d0 fs/open.c:1406 do_sys_open fs/open.c:1421 [inline] __do_sys_openat fs/open.c:1437 [inline] __se_sys_openat fs/open.c:1432 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1432 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88807f0e5180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807f0e5200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807f0e5280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807f0e5300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807f0e5380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================