================================================================== BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x1243/0x37d0 fs/jfs/jfs_dtree.c:-1 Read of size 1 at addr ffff88805f799b55 by task syz.5.934/9620 CPU: 1 PID: 9620 Comm: syz.5.934 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 dtSplitPage+0x1243/0x37d0 fs/jfs/jfs_dtree.c:-1 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline] dtInsert+0x1072/0x5de0 fs/jfs/jfs_dtree.c:871 jfs_mkdir+0x75c/0xac0 fs/jfs/namei.c:270 vfs_mkdir+0x296/0x440 fs/namei.c:4121 do_mkdirat+0x1dc/0x450 fs/namei.c:4144 __do_sys_mkdirat fs/namei.c:4159 [inline] __se_sys_mkdirat fs/namei.c:4157 [inline] __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4157 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f224af9c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f224bd75028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f224b215fa0 RCX: 00007f224af9c799 RDX: 00000000000001c0 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f224b032c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f224b216038 R14: 00007f224b215fa0 R15: 00007fffee1d75a8 Allocated by task 9620: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc_lru+0x111/0x2d0 mm/slub.c:3526 alloc_inode_sb include/linux/fs.h:2946 [inline] jfs_alloc_inode+0x28/0x60 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] iget_locked+0x1ad/0x840 fs/inode.c:1359 jfs_iget+0x24/0x440 fs/jfs/inode.c:29 jfs_lookup+0x221/0x420 fs/jfs/namei.c:1469 __lookup_slow+0x2a1/0x400 fs/namei.c:1702 lookup_slow+0x53/0x70 fs/namei.c:1719 walk_component+0x2be/0x3f0 fs/namei.c:2010 lookup_last fs/namei.c:2467 [inline] path_lookupat+0x169/0x440 fs/namei.c:2491 filename_lookup+0x228/0x560 fs/namei.c:2520 user_path_at_empty+0x42/0x60 fs/namei.c:2917 user_path_at include/linux/namei.h:57 [inline] __do_sys_chdir fs/open.c:551 [inline] __se_sys_chdir+0x9c/0x280 fs/open.c:545 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 destroy_inode fs/inode.c:316 [inline] evict+0x835/0x8d0 fs/inode.c:720 jfs_umount+0x260/0x3c0 fs/jfs/jfs_umount.c:89 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x134/0x2b0 fs/super.c:693 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x43b/0x4d0 fs/namespace.c:1259 task_work_run+0x1d4/0x260 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88805f799280 which belongs to the cache jfs_ip of size 2240 The buggy address is located 21 bytes to the right of allocated 2240-byte region [ffff88805f799280, ffff88805f799b40) The buggy address belongs to the physical page: page:ffffea00017de600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5f798 head:ffffea00017de600 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802f79d101 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888142688140 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff88802f79d101 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 9278, tgid 9277 (syz.0.862), ts 407275162131, free_ts 393154103578 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc_lru+0x1aa/0x2d0 mm/slub.c:3526 alloc_inode_sb include/linux/fs.h:2946 [inline] jfs_alloc_inode+0x28/0x60 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049 new_inode+0x22/0x1b0 fs/inode.c:1075 jfs_fill_super+0x39c/0xad0 fs/jfs/super.c:544 mount_bdev+0x221/0x2d0 fs/super.c:1643 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x319/0x400 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] __kmem_cache_alloc_node+0x13a/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] drm_atomic_state_alloc+0xa8/0x100 drivers/gpu/drm/drm_atomic.c:174 drm_client_modeset_commit_atomic+0x119/0x7b0 drivers/gpu/drm/drm_client_modeset.c:998 drm_client_modeset_commit_locked+0xcb/0x4c0 drivers/gpu/drm/drm_client_modeset.c:1160 pan_display_atomic drivers/gpu/drm/drm_fb_helper.c:1386 [inline] drm_fb_helper_pan_display+0x3e7/0xbd0 drivers/gpu/drm/drm_fb_helper.c:1446 fb_pan_display+0x39f/0x690 drivers/video/fbdev/core/fbmem.c:731 Memory state around the buggy address: ffff88805f799a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805f799a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805f799b00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff88805f799b80: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff88805f799c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================