ci2 starts bisection 2023-11-26 13:38:53.654477991 +0000 UTC m=+244958.455070555
bisecting fixing commit since 09045dae0d902f9f78901a26c7ff1714976a38f9
building syzkaller on 0b6a67ac4b0dc26f43030c5edd01c9175f13b784
ensuring issue is reproducible on original commit 09045dae0d902f9f78901a26c7ff1714976a38f9

testing commit 09045dae0d902f9f78901a26c7ff1714976a38f9 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 81499ef1806daea3860db8308af1c5c7c7daa312771d39e7b719c51fb2fa4d62
run #0: crashed: KASAN: use-after-free Read in ext4_find_extent
run #1: crashed: KASAN: use-after-free Read in ext4_find_extent
run #2: crashed: KASAN: use-after-free Read in ext4_find_extent
run #3: crashed: KASAN: use-after-free Read in ext4_find_extent
run #4: crashed: KASAN: use-after-free Read in ext4_find_extent
run #5: crashed: KASAN: use-after-free Read in ext4_find_extent
run #6: crashed: KASAN: use-after-free Read in ext4_find_extent
run #7: crashed: KASAN: use-after-free Read in ext4_find_extent
run #8: crashed: KASAN: use-after-free Read in ext4_find_extent
run #9: crashed: KASAN: out-of-bounds Read in ext4_find_extent
run #10: crashed: KASAN: use-after-free Read in ext4_find_extent
run #11: crashed: KASAN: use-after-free Read in ext4_find_extent
run #12: crashed: KASAN: out-of-bounds Read in ext4_find_extent
run #13: crashed: KASAN: use-after-free Read in ext4_find_extent
run #14: crashed: KASAN: use-after-free Read in ext4_find_extent
run #15: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent
run #16: crashed: KASAN: use-after-free Read in ext4_find_extent
run #17: crashed: KASAN: use-after-free Read in ext4_find_extent
run #18: crashed: KASAN: use-after-free Read in ext4_find_extent
run #19: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
check whether we can drop unnecessary instrumentation
disabling configs for [LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP HANG], they are not needed
testing commit 09045dae0d902f9f78901a26c7ff1714976a38f9 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 74e697fcbe90b46474d8530cde78fc7deea7d08ed055e9c4b8b61f0aebbffac9
run #0: crashed: KASAN: use-after-free Read in ext4_find_extent
run #1: crashed: KASAN: use-after-free Read in ext4_find_extent
run #2: crashed: KASAN: out-of-bounds Read in ext4_find_extent
run #3: crashed: KASAN: use-after-free Read in ext4_find_extent
run #4: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent
run #5: crashed: invalid opcode in ext4_split_extent_at
run #6: crashed: KASAN: use-after-free Read in ext4_find_extent
run #7: crashed: KASAN: use-after-free Read in ext4_find_extent
run #8: crashed: KASAN: use-after-free Read in ext4_find_extent
run #9: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
the bug reproduces without the instrumentation
disabling configs for [BUG LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN], they are not needed
kconfig minimization: base=3820 full=7527 leaves diff=1999
split chunks (needed=false): <1999>
split chunk #0 of len 1999 into 5 parts
testing without sub-chunk 1/5
disabling configs for [HANG LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP], they are not needed
testing commit 09045dae0d902f9f78901a26c7ff1714976a38f9 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: b1535462161752a6ed67ab8838ce37bd58e20c38fc31870780d4b42e047a0fd7
run #0: crashed: KASAN: use-after-free Read in ext4_find_extent
run #1: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent
run #2: crashed: KASAN: use-after-free Read in ext4_find_extent
run #3: crashed: KASAN: use-after-free Read in ext4_find_extent
run #4: crashed: KASAN: use-after-free Read in ext4_find_extent
run #5: crashed: KASAN: use-after-free Read in ext4_find_extent
run #6: crashed: KASAN: use-after-free Read in ext4_find_extent
run #7: crashed: KASAN: use-after-free Read in ext4_find_extent
run #8: crashed: KASAN: use-after-free Read in ext4_find_extent
run #9: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 2/5
disabling configs for [HANG LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP], they are not needed
testing commit 09045dae0d902f9f78901a26c7ff1714976a38f9 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 4f69fd62d1e49f9ded9704403826a21be4bc6b3faca14c49403ef8127954d653
run #0: crashed: KASAN: use-after-free Read in ext4_find_extent
run #1: crashed: KASAN: use-after-free Read in ext4_find_extent
run #2: crashed: KASAN: use-after-free Read in ext4_find_extent
run #3: crashed: KASAN: use-after-free Read in ext4_find_extent
run #4: crashed: KASAN: use-after-free Read in ext4_find_extent
run #5: crashed: KASAN: use-after-free Read in ext4_find_extent
run #6: crashed: KASAN: use-after-free Read in ext4_find_extent
run #7: crashed: KASAN: out-of-bounds Read in ext4_find_extent
run #8: crashed: KASAN: use-after-free Read in ext4_find_extent
run #9: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 3/5
disabling configs for [LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP HANG], they are not needed
testing commit 09045dae0d902f9f78901a26c7ff1714976a38f9 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: f0c51ff8d923a3d181dbe372226a71299bc106ae63e0eecbf9b158f210c1c31c
all runs: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 4/5
disabling configs for [LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP HANG], they are not needed
testing commit 09045dae0d902f9f78901a26c7ff1714976a38f9 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: a69226761d708682ebbcb47cb874851043198f339e5e42280707903268a6fb00
run #0: crashed: KASAN: use-after-free Read in ext4_find_extent
run #1: crashed: KASAN: use-after-free Read in ext4_find_extent
run #2: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent
run #3: crashed: KASAN: use-after-free Read in ext4_find_extent
run #4: crashed: KASAN: use-after-free Read in ext4_find_extent
run #5: crashed: KASAN: use-after-free Read in ext4_find_extent
run #6: crashed: KASAN: use-after-free Read in ext4_find_extent
run #7: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent
run #8: crashed: KASAN: use-after-free Read in ext4_find_extent
run #9: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
the chunk can be dropped
testing without sub-chunk 5/5
disabling configs for [LOCKDEP ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed
testing commit 09045dae0d902f9f78901a26c7ff1714976a38f9 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: ab2416b99b5a72a20447a7d8a9282b809774eba7e8c0c844d8fd3993958ff958
all runs: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
the chunk can be dropped
disabling configs for [HANG LEAK UBSAN BUG LOCKDEP ATOMIC_SLEEP], they are not needed
testing current HEAD 69e434a1cb2146a70062d89d507b6132fa38bfe1
testing commit 69e434a1cb2146a70062d89d507b6132fa38bfe1 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 2bc7f09b1cfc8768365f5c0f727f563889452d25dda91c85f941b7279abdc20d
all runs: crashed: KASAN: use-after-free Read in ext4_find_extent
representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN]
crash still not fixed/happens on the oldest tested release
revisions tested: 8, total time: 56m37.400387076s (build: 29m50.265882566s, test: 24m5.4186375s)
crash still not fixed or there were kernel test errors
commit msg: Linux 6.1.63
crash: KASAN: use-after-free Read in ext4_find_extent
==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0xb24/0xcd0 fs/ext4/extents.c:953
Read of size 4 at addr ffff888124e7ca5c by task syz-executor.0/1509

CPU: 0 PID: 1509 Comm: syz-executor.0 Not tainted 6.1.63-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+0xf4/0x251 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
 ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
 ext4_find_extent+0xb24/0xcd0 fs/ext4/extents.c:953
 ext4_ext_map_blocks+0x297/0x62f0 fs/ext4/extents.c:4103
 ext4_map_blocks+0x82a/0x1810 fs/ext4/inode.c:651
 _ext4_get_block+0x1d0/0x540 fs/ext4/inode.c:798
 __block_write_begin_int+0x32a/0x1150 fs/buffer.c:1991
 __block_write_begin fs/buffer.c:2041 [inline]
 block_page_mkwrite+0x218/0x400 fs/buffer.c:2510
 ext4_page_mkwrite+0x5d9/0xf20 fs/ext4/inode.c:6255
 do_page_mkwrite+0x149/0x410 mm/memory.c:2992
 wp_page_shared+0x146/0x540 mm/memory.c:3341
 handle_pte_fault mm/memory.c:5011 [inline]
 __handle_mm_fault mm/memory.c:5135 [inline]
 handle_mm_fault+0x91a/0x2bf0 mm/memory.c:5256
 do_user_addr_fault arch/x86/mm/fault.c:1380 [inline]
 handle_page_fault arch/x86/mm/fault.c:1471 [inline]
 exc_page_fault+0x22a/0x5e0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7f9b88dcfcc7
Code: ce 48 ff c7 48 01 fe 48 8d 54 11 80 0f 1f 80 00 00 00 00 c5 fe 6f 0e c5 fe 6f 56 20 c5 fe 6f 5e 40 c5 fe 6f 66 60 48 83 ee 80 <c5> fd 7f 0f c5 fd 7f 57 20 c5 fd 7f 5f 40 c5 fd 7f 67 60 48 83 ef
RSP: 002b:00007fff65a262e8 EFLAGS: 00010203
RAX: 0000000020003600 RBX: 00007fff65a263f8 RCX: 0000000020003600
RDX: 00000000200036a9 RSI: 00007f9b889927b0 RDI: 0000000020003620
RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f9b88f0df8c
R10: 00007fff65a26420 R11: 0000000000000246 R12: 00007f9b889926f0
R13: fffffffffffffffe R14: 00007f9b88972000 R15: 00007f9b889926f8
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0004939f00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x124e7c
flags: 0x200000000000000(node=0|zone=2)
raw: 0200000000000000 ffffea000493a1c8 ffffea000493a6c8 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x152c4a(GFP_NOFS|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL|__GFP_MOVABLE), pid 1503, tgid 1503 (syz-executor.0), ts 51960974404, free_ts 51980188823
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x286/0x2b0 mm/page_alloc.c:2513
 prep_new_page mm/page_alloc.c:2520 [inline]
 get_page_from_freelist+0x2ba7/0x2de0 mm/page_alloc.c:4279
 __alloc_pages+0x251/0x640 mm/page_alloc.c:5545
 filemap_alloc_folio+0xc2/0x390 mm/filemap.c:971
 page_cache_ra_unbounded+0x1d1/0x650 mm/readahead.c:248
 do_sync_mmap_readahead+0x5fc/0x7d0 mm/filemap.c:3098
 filemap_fault+0x650/0x1230 mm/filemap.c:3190
 __do_fault+0x10f/0x380 mm/memory.c:4241
 do_shared_fault mm/memory.c:4647 [inline]
 do_fault mm/memory.c:4725 [inline]
 handle_pte_fault mm/memory.c:4993 [inline]
 __handle_mm_fault mm/memory.c:5135 [inline]
 handle_mm_fault+0x1558/0x2bf0 mm/memory.c:5256
 do_user_addr_fault arch/x86/mm/fault.c:1380 [inline]
 handle_page_fault arch/x86/mm/fault.c:1471 [inline]
 exc_page_fault+0x22a/0x5e0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
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+0xca9/0xd80 mm/page_alloc.c:3358
 free_unref_page_list+0xaa/0x690 mm/page_alloc.c:3499
 release_pages+0x1763/0x1900 mm/swap.c:1055
 __pagevec_release+0x62/0xd0 mm/swap.c:1075
 pagevec_release include/linux/pagevec.h:71 [inline]
 folio_batch_release include/linux/pagevec.h:135 [inline]
 truncate_inode_pages_range+0x351/0xbf0 mm/truncate.c:373
 ext4_evict_inode+0x26a/0x1240 fs/ext4/inode.c:210
 evict+0x263/0x630 fs/inode.c:664
 dispose_list fs/inode.c:697 [inline]
 evict_inodes+0x52c/0x590 fs/inode.c:747
 generic_shutdown_super+0x8e/0x2c0 fs/super.c:480
 kill_block_super+0x75/0xb0 fs/super.c:1459
 deactivate_locked_super+0x71/0xd0 fs/super.c:332
 cleanup_mnt+0x2bd/0x330 fs/namespace.c:1186
 task_work_run+0x206/0x280 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xa9/0xc0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x64/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x27/0x1c0 kernel/entry/common.c:297

Memory state around the buggy address:
 ffff888124e7c900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888124e7c980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888124e7ca00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                    ^
 ffff888124e7ca80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888124e7cb00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================