==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0xbab/0xdb0 fs/ext4/extents.c:953
Read of size 4 at addr ffff8881131f5fb4 by task kworker/u4:3/446

CPU: 1 PID: 446 Comm: kworker/u4:3 Not tainted 6.1.25-syzkaller-00071-gb1644a0031cf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x158/0x4e0 mm/kasan/report.c:395
 kasan_report+0x13c/0x170 mm/kasan/report.c:495
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:350
 ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
 ext4_find_extent+0xbab/0xdb0 fs/ext4/extents.c:953
 ext4_ext_map_blocks+0x255/0x71e0 fs/ext4/extents.c:4103
 ext4_map_blocks+0xa42/0x1ce0 fs/ext4/inode.c:651
 mpage_map_one_extent fs/ext4/inode.c:2420 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2473 [inline]
 ext4_writepages+0x1746/0x3f80 fs/ext4/inode.c:2841
 do_writepages+0x385/0x620 mm/page-writeback.c:2469
 __writeback_single_inode+0xdc/0xb80 fs/fs-writeback.c:1590
 writeback_sb_inodes+0xb33/0x18f0 fs/fs-writeback.c:1881
 wb_writeback+0x3b9/0x9f0 fs/fs-writeback.c:2055
 wb_do_writeback fs/fs-writeback.c:2198 [inline]
 wb_workfn+0x399/0x1030 fs/fs-writeback.c:2238
 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2289
 worker_thread+0xa5d/0x1260 kernel/workqueue.c:2436
 kthread+0x26d/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Allocated by task 187:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x53/0x2c0 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+0x175/0x2c0 mm/slub.c:3422
 getname_flags+0xba/0x520 fs/namei.c:139
 getname+0x19/0x20 fs/namei.c:218
 do_sys_openat2+0xd2/0x500 fs/open.c:1304
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_openat fs/open.c:1342 [inline]
 __se_sys_openat fs/open.c:1337 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1337
 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 187:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x131/0x180 mm/kasan/common.c:236
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:244
 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+0x291/0x510 mm/slub.c:3683
 putname+0xfa/0x150 fs/namei.c:271
 do_sys_openat2+0x42b/0x500 fs/open.c:1319
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_openat fs/open.c:1342 [inline]
 __se_sys_openat fs/open.c:1337 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1337
 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

The buggy address belongs to the object at ffff8881131f5500
 which belongs to the cache names_cache of size 4096
The buggy address is located 2740 bytes inside of
 4096-byte region [ffff8881131f5500, ffff8881131f6500)

The buggy address belongs to the physical page:
page:ffffea00044c7c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1131f0
head:ffffea00044c7c00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff8881001998c0
raw: 0000000000000000 0000000000070007 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 187, tgid 187 (udevd), ts 44351513063, free_ts 44267619911
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e2/0x1f0 mm/page_alloc.c:2533
 prep_new_page mm/page_alloc.c:2540 [inline]
 get_page_from_freelist+0x2e7a/0x2f50 mm/page_alloc.c:4292
 __alloc_pages+0x3c2/0x7d0 mm/page_alloc.c:5559
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0xce/0x4c0 mm/slub.c:1992
 ___slab_alloc+0x6f9/0xb80 mm/slub.c:3180
 __slab_alloc+0x5d/0xa0 mm/slub.c:3279
 slab_alloc_node mm/slub.c:3364 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x1b9/0x2c0 mm/slub.c:3422
 getname_flags+0xba/0x520 fs/namei.c:139
 getname+0x19/0x20 fs/namei.c:218
 do_sys_openat2+0xd2/0x500 fs/open.c:1304
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_openat fs/open.c:1342 [inline]
 __se_sys_openat fs/open.c:1337 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1337
 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
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1460 [inline]
 free_pcp_prepare mm/page_alloc.c:1533 [inline]
 free_unref_page_prepare+0x83d/0x850 mm/page_alloc.c:3388
 free_unref_page+0x8d/0x480 mm/page_alloc.c:3484
 free_the_page mm/page_alloc.c:770 [inline]
 __free_pages+0x61/0xf0 mm/page_alloc.c:5648
 __free_slab+0xce/0x1a0 mm/slub.c:2016
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x165/0x1a0 mm/slub.c:2586
 put_cpu_partial+0xa9/0x100 mm/slub.c:2662
 __slab_free+0x1c8/0x280 mm/slub.c:3538
 do_slab_free mm/slub.c:3615 [inline]
 ___cache_free+0xc6/0xd0 mm/slub.c:3668
 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:168
 qlist_free_all+0x52/0xc0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x15a/0x180 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x53/0x2c0 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+0x175/0x2c0 mm/slub.c:3422
 getname_flags+0xba/0x520 fs/namei.c:139
 getname fs/namei.c:218 [inline]
 __do_sys_mkdir fs/namei.c:4081 [inline]
 __se_sys_mkdir fs/namei.c:4079 [inline]
 __x64_sys_mkdir+0x5f/0x80 fs/namei.c:4079

Memory state around the buggy address:
 ffff8881131f5e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881131f5f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881131f5f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff8881131f6000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881131f6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
------------[ cut here ]------------
kernel BUG at fs/ext4/inode.c:2432!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 446 Comm: kworker/u4:3 Tainted: G    B              6.1.25-syzkaller-00071-gb1644a0031cf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:mpage_map_one_extent fs/ext4/inode.c:2432 [inline]
RIP: 0010:mpage_map_and_submit_extent fs/ext4/inode.c:2473 [inline]
RIP: 0010:ext4_writepages+0x3d17/0x3f80 fs/ext4/inode.c:2841
Code: e8 6e d4 83 ff be 00 10 00 00 48 c7 c7 d0 82 4b 86 4c 89 f2 e8 ea dd a1 00 e9 22 fb ff ff e8 50 d4 83 ff 0f 0b e8 49 d4 83 ff <0f> 0b e8 c2 8d e3 02 65 8b 05 23 a6 12 7e 41 89 c7 4c 89 f8 48 c1
RSP: 0018:ffffc90002da7000 EFLAGS: 00010293
RAX: ffffffff81ef6b27 RBX: dffffc0000000000 RCX: ffff88810db190c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002da7410 R08: ffffffff81ef4817 R09: ffffed102422f689
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90002da7330
R13: 0000000000000000 R14: ffff88812117b468 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5bfb90652e CR3: 000000000620f000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 do_writepages+0x385/0x620 mm/page-writeback.c:2469
 __writeback_single_inode+0xdc/0xb80 fs/fs-writeback.c:1590
 writeback_sb_inodes+0xb33/0x18f0 fs/fs-writeback.c:1881
 wb_writeback+0x3b9/0x9f0 fs/fs-writeback.c:2055
 wb_do_writeback fs/fs-writeback.c:2198 [inline]
 wb_workfn+0x399/0x1030 fs/fs-writeback.c:2238
 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2289
 worker_thread+0xa5d/0x1260 kernel/workqueue.c:2436
 kthread+0x26d/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:mpage_map_one_extent fs/ext4/inode.c:2432 [inline]
RIP: 0010:mpage_map_and_submit_extent fs/ext4/inode.c:2473 [inline]
RIP: 0010:ext4_writepages+0x3d17/0x3f80 fs/ext4/inode.c:2841
Code: e8 6e d4 83 ff be 00 10 00 00 48 c7 c7 d0 82 4b 86 4c 89 f2 e8 ea dd a1 00 e9 22 fb ff ff e8 50 d4 83 ff 0f 0b e8 49 d4 83 ff <0f> 0b e8 c2 8d e3 02 65 8b 05 23 a6 12 7e 41 89 c7 4c 89 f8 48 c1
RSP: 0018:ffffc90002da7000 EFLAGS: 00010293
RAX: ffffffff81ef6b27 RBX: dffffc0000000000 RCX: ffff88810db190c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002da7410 R08: ffffffff81ef4817 R09: ffffed102422f689
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90002da7330
R13: 0000000000000000 R14: ffff88812117b468 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5bfb90652e CR3: 000000000620f000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400