ci2 starts bisection 2025-12-10 19:19:51.765662343 +0000 UTC m=+1230603.942785390 bisecting fixing commit since d0c22de9995b624f563bc5004d44ac2655712a56 building syzkaller on ed351ea732d889c7798e7f0226bcaec65a8a6b52 ensuring issue is reproducible on original commit d0c22de9995b624f563bc5004d44ac2655712a56 testing commit d0c22de9995b624f563bc5004d44ac2655712a56 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 017c7aa0a97446e3a03252bb4ffc610a1e1fafa237e48ad9d057ea3996e625ef run #0: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #1: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #2: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #3: crashed: KASAN: use-after-free Read in ext4_find_extent run #4: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: slab-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: slab-out-of-bounds Read in ext4_find_extent run #9: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #10: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #11: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #12: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #13: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #14: crashed: KASAN: use-after-free Read in ext4_find_extent run #15: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #16: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #17: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #18: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #19: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent representative crash: KASAN: slab-use-after-free Read in ext4_find_extent, types: [KASAN-USE-AFTER-FREE-READ] check whether we can drop unnecessary instrumentation disabling configs for [ubsan bug_or_warning locking atomic_sleep hang memleak], they are not needed testing commit d0c22de9995b624f563bc5004d44ac2655712a56 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 7b6f279950ae2cddd467a93dee2df26733fd7ba441da6045b5e350097b670bfb run #0: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #1: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #2: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #3: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #4: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #5: crashed: KASAN: use-after-free Read in ext4_find_extent run #6: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #7: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #8: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #9: crashed: KASAN: use-after-free Read in ext4_find_extent representative crash: KASAN: slab-out-of-bounds Read in ext4_find_extent, types: [KASAN-READ KASAN-USE-AFTER-FREE-READ] the bug reproduces without the instrumentation disabling configs for [atomic_sleep hang memleak ubsan bug_or_warning locking], they are not needed kconfig minimization: base=4109 full=8326 leaves diff=2154 split chunks (needed=false): <2154> split chunk #0 of len 2154 into 5 parts testing without sub-chunk 1/5 disabling configs for [ubsan bug_or_warning locking atomic_sleep hang memleak], they are not needed testing commit d0c22de9995b624f563bc5004d44ac2655712a56 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 09b0cb0e8d555b08c87e91785d2055f3f28f9349efab8f9a13aca6af02ff9c13 run #0: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #1: crashed: KASAN: slab-use-after-free Read in ext4_ext_correct_indexes run #2: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #3: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #4: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #5: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #6: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #7: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #8: crashed: KASAN: slab-out-of-bounds Read in ext4_ext_insert_extent run #9: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent representative crash: KASAN: slab-out-of-bounds Read in ext4_find_extent, types: [KASAN-READ KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 2/5 disabling configs for [bug_or_warning locking atomic_sleep hang memleak ubsan], they are not needed testing commit d0c22de9995b624f563bc5004d44ac2655712a56 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: dadf84b74e938ae24db63fe5dba514a65c59a8a4fdc00dddc8eda041b1122a4b run #0: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #1: crashed: KASAN: slab-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: slab-use-after-free Read in ext4_find_extent run #4: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #6: crashed: KASAN: use-after-free Read in ext4_find_extent run #7: crashed: KASAN: slab-out-of-bounds Read in ext4_ext_insert_extent run #8: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #9: crashed: KASAN: slab-use-after-free Read in ext4_find_extent representative crash: KASAN: slab-use-after-free Read in ext4_find_extent, types: [KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 3/5 disabling configs for [atomic_sleep hang memleak ubsan bug_or_warning locking], they are not needed testing commit d0c22de9995b624f563bc5004d44ac2655712a56 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: f0e6814c81207ba6898b9138f02a8e1f82248052b3f3031fa2757bb9ff4084a3 run #0: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #1: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #2: crashed: KASAN: slab-use-after-free Read in ext4_ext_correct_indexes run #3: crashed: KASAN: use-after-free Read in ext4_find_extent run #4: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: use-after-free Read in ext4_find_extent run #6: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #7: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #8: crashed: KASAN: use-after-free Read in ext4_find_extent run #9: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent representative crash: KASAN: slab-use-after-free Read in ext4_ext_insert_extent, types: [KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 4/5 disabling configs for [hang memleak ubsan bug_or_warning locking atomic_sleep], they are not needed testing commit d0c22de9995b624f563bc5004d44ac2655712a56 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 11595f1e78432866a170eb75d63597653a047ecdf66623b655b1ff7c7141e8dc run #0: crashed: KASAN: use-after-free Read in ext4_ext_correct_indexes run #1: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #2: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #3: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #4: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #6: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #7: crashed: KASAN: slab-out-of-bounds Read in ext4_ext_insert_extent run #8: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #9: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent representative crash: KASAN: use-after-free Read in ext4_ext_correct_indexes, types: [KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 5/5 disabling configs for [locking atomic_sleep hang memleak ubsan bug_or_warning], they are not needed testing commit d0c22de9995b624f563bc5004d44ac2655712a56 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 93ed1d5d4692d0bafcfae4d70914f91e967a427137cff9d022445abc4b7a5fc8 run #0: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #1: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #2: crashed: KASAN: slab-out-of-bounds Read in ext4_ext_insert_extent run #3: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #4: crashed: KASAN: slab-out-of-bounds Read in ext4_ext_insert_extent run #5: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #6: crashed: KASAN: use-after-free Read in ext4_find_extent run #7: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent run #8: crashed: KASAN: slab-out-of-bounds Read in ext4_ext_insert_extent run #9: crashed: KASAN: slab-use-after-free Read in ext4_ext_insert_extent representative crash: KASAN: slab-use-after-free Read in ext4_ext_insert_extent, types: [KASAN-USE-AFTER-FREE-READ KASAN-READ] the chunk can be dropped disabling configs for [memleak ubsan bug_or_warning locking atomic_sleep hang], they are not needed testing current HEAD 0048fbb4011ec55c32d3148b2cda56433f273375 testing commit 0048fbb4011ec55c32d3148b2cda56433f273375 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 832517da516ababc458f5ea44b3ff0916517da66ac4a41b76a43baf4dd879ecb run #0: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #1: crashed: KASAN: slab-use-after-free Read in ext4_ext_correct_indexes run #2: crashed: KASAN: use-after-free Read in ext4_find_extent run #3: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #4: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: slab-use-after-free Read in ext4_ext_correct_indexes run #6: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #7: crashed: KASAN: slab-use-after-free Read in ext4_find_extent run #8: crashed: KASAN: slab-out-of-bounds Read in ext4_find_extent run #9: crashed: KASAN: slab-use-after-free Read in ext4_find_extent representative crash: KASAN: slab-use-after-free Read in ext4_ext_correct_indexes, types: [KASAN-USE-AFTER-FREE-READ KASAN-READ] crash still not fixed/happens on the oldest tested release revisions tested: 8, total time: 2h5m32.549978893s (build: 1h16m37.049764024s, test: 37m22.701844459s) crash still not fixed or there were kernel test errors commit msg: Merge tag 'locking-futex-2025-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip crash: KASAN: slab-use-after-free Read in ext4_ext_correct_indexes ================================================================== BUG: KASAN: slab-use-after-free in ext4_ext_correct_indexes+0x6c/0x520 fs/ext4/extents.c:1712 Read of size 8 at addr ffff888126669350 by task syz.0.129/4719 CPU: 0 UID: 0 PID: 4719 Comm: syz.0.129 Not tainted syzkaller #0 PREEMPT(none) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xf4/0x170 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 ext4_ext_correct_indexes+0x6c/0x520 fs/ext4/extents.c:1712 ext4_ext_insert_extent+0x2981/0x4b70 fs/ext4/extents.c:2188 ext4_ext_map_blocks+0x1adb/0x57d0 fs/ext4/extents.c:4404 ext4_map_create_blocks fs/ext4/inode.c:613 [inline] ext4_map_blocks+0x5e5/0x1310 fs/ext4/inode.c:816 _ext4_get_block+0x199/0x3c0 fs/ext4/inode.c:916 ext4_get_block_unwritten+0x17/0xa0 fs/ext4/inode.c:949 ext4_block_write_begin+0x785/0xd50 fs/ext4/inode.c:1203 ext4_write_begin+0x8dd/0x13f0 fs/ext4/inode.c:-1 ext4_da_write_begin+0x2d5/0xa30 fs/ext4/inode.c:3130 generic_perform_write+0x26f/0x630 mm/filemap.c:4314 ext4_buffered_write_iter+0x2c3/0x510 fs/ext4/file.c:299 ext4_file_write_iter+0x1fc/0x12a0 fs/ext4/file.c:-1 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x56b/0xc70 fs/read_write.c:686 ksys_pwrite64 fs/read_write.c:793 [inline] __do_sys_pwrite64 fs/read_write.c:801 [inline] __se_sys_pwrite64 fs/read_write.c:798 [inline] __x64_sys_pwrite64+0x139/0x1c0 fs/read_write.c:798 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8f/0x2d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb277b6e969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb2775df038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007fb277d95fa0 RCX: 00007fb277b6e969 RDX: 000000000000fdef RSI: 0000200000000140 RDI: 0000000000000004 RBP: 00007fb277bf0ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000fecc R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb277d95fa0 R15: 00007ffe7bab68e8 Allocated by task 793: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __kmalloc_cache_noprof+0x384/0x660 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] slab_free_hook mm/slub.c:2492 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x158/0x5b0 mm/slub.c:6774 fput_close_sync+0xd7/0x190 fs/file_table.c:573 __do_sys_close fs/open.c:1573 [inline] __se_sys_close fs/open.c:1558 [inline] __x64_sys_close+0x7b/0xc0 fs/open.c:1558 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8f/0x2d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kfree+0x1af/0x550 mm/slub.c:6871 slab_free_after_rcu_debug+0x5d/0x250 mm/slub.c:6709 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xc4b/0x15e0 kernel/rcu/tree.c:2857 handle_softirqs+0x19d/0x500 kernel/softirq.c:622 run_ksoftirqd+0x28/0x40 kernel/softirq.c:1063 smpboot_thread_fn+0x3f7/0x7d0 kernel/smpboot.c:160 kthread+0x59b/0x690 kernel/kthread.c:463 ret_from_fork+0x23b/0x520 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3119 [inline] call_rcu+0x14a/0x790 kernel/rcu/tree.c:3239 slab_free_hook mm/slub.c:2504 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x426/0x5b0 mm/slub.c:6774 fput_close_sync+0xd7/0x190 fs/file_table.c:573 __do_sys_close fs/open.c:1573 [inline] __se_sys_close fs/open.c:1558 [inline] __x64_sys_close+0x7b/0xc0 fs/open.c:1558 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8f/0x2d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888126669340 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 16 bytes inside of freed 32-byte region [ffff888126669340, ffff888126669360) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x126669 flags: 0x200000000000000(node=0|zone=2) page_type: f5(slab) raw: 0200000000000000 ffff888100041780 ffffea0004ba1c40 dead000000000002 raw: 0000000000000000 0000000000400040 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP), pid 1403, tgid 1403 (modprobe), ts 44221652420, free_ts 44220935453 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x15a/0x190 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x29f0/0x2bb0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x26b/0x460 mm/page_alloc.c:5210 alloc_pages_mpol+0xcb/0x270 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x81/0x350 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xcc9/0x1580 mm/slub.c:4651 __slab_alloc+0x54/0xc0 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] __kmalloc_cache_noprof+0x3c2/0x660 mm/slub.c:5766 kmalloc_noprof include/linux/slab.h:957 [inline] slab_free_hook mm/slub.c:2492 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x158/0x5b0 mm/slub.c:6774 exit_mmap+0x422/0x830 mm/mmap.c:1302 __mmput+0x62/0x290 kernel/fork.c:1173 exit_mm+0x11b/0x1b0 kernel/exit.c:581 do_exit+0x516/0x1d60 kernel/exit.c:959 do_group_exit+0x1b1/0x280 kernel/exit.c:1112 __do_sys_exit_group kernel/exit.c:1123 [inline] __se_sys_exit_group kernel/exit.c:1121 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121 __pfx_rseq_debug_syscall_return+0x0/0x10 arch/x86/include/generated/asm/syscalls_64.h:232 page last free pid 1403 tgid 1403 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xa66/0xbd0 mm/page_alloc.c:2943 tlb_batch_list_free mm/mmu_gather.c:159 [inline] tlb_finish_mmu+0x134/0x190 mm/mmu_gather.c:500 exit_mmap+0x374/0x830 mm/mmap.c:1290 __mmput+0x62/0x290 kernel/fork.c:1173 exit_mm+0x11b/0x1b0 kernel/exit.c:581 do_exit+0x516/0x1d60 kernel/exit.c:959 do_group_exit+0x1b1/0x280 kernel/exit.c:1112 __do_sys_exit_group kernel/exit.c:1123 [inline] __se_sys_exit_group kernel/exit.c:1121 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121 __pfx_rseq_debug_syscall_return+0x0/0x10 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8f/0x2d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888126669200: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ffff888126669280: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc >ffff888126669300: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff888126669380: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ffff888126669400: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ==================================================================