ci2 starts bisection 2026-02-23 18:50:08.438717229 +0000 UTC m=+31601.437891913 bisecting fixing commit since fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df building syzkaller on e28266709dd2a1d1452d4a5bbf271700e10335c6 ensuring issue is reproducible on original commit fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df testing commit fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 kernel signature: f351cf56996ec2248888e32bbe9515db52b016edff51d6c2436c96668a76a7c1 run #0: crashed: KASAN: out-of-bounds Read in ext4_ext_insert_extent run #1: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #2: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #3: crashed: KASAN: use-after-free Read in ext4_find_extent run #4: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #5: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #6: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #7: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #8: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #9: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #10: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #11: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #12: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #13: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #14: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #15: crashed: panic: runtime error: invalid memory address or nil pointer dereference run #16: crashed: KASAN: use-after-free Read in ext4_find_extent run #17: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #18: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #19: crashed: KASAN: use-after-free Write in ext4_ext_remove_space representative crash: KASAN: use-after-free Write in ext4_ext_remove_space, types: [KASAN-USE-AFTER-FREE-WRITE 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 fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 kernel signature: 5ffa9bae1278393192b4b51c502d0ade7dfe89e11fd756baf0b88960d927a30e run #0: crashed: KASAN: use-after-free Read in ext4_find_extent run #1: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #2: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #3: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #4: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: out-of-bounds Read in ext4_find_extent run #6: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #7: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #8: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #9: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN-USE-AFTER-FREE-READ KASAN-USE-AFTER-FREE-WRITE] the bug reproduces without the instrumentation disabling configs for [hang memleak ubsan bug_or_warning locking atomic_sleep], they are not needed kconfig minimization: base=4788 full=6023 leaves diff=246 split chunks (needed=false): <246> split chunk #0 of len 246 into 5 parts testing without sub-chunk 1/5 disabling configs for [bug_or_warning locking atomic_sleep hang memleak ubsan], they are not needed testing commit fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 kernel signature: cf014291cde784b390ffe979957c2810b42e18ce295e44dfbc81a361e7eeb08a run #0: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #1: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #2: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #3: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #4: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #6: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #7: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #8: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #9: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent representative crash: KASAN: use-after-free Write in ext4_ext_remove_space, types: [KASAN-USE-AFTER-FREE-WRITE KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 2/5 disabling configs for [atomic_sleep hang memleak ubsan bug_or_warning locking], they are not needed testing commit fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 kernel signature: 50b08baaaf39cbeae5d3cda097b202cba522a3e5b4fca8e447f8c4fc5428227c run #0: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #1: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #2: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #3: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #4: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #5: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #6: crashed: KASAN: use-after-free Read in ext4_ext_insert_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_ext_insert_extent representative crash: KASAN: use-after-free Read in ext4_ext_remove_space, types: [KASAN-USE-AFTER-FREE-READ KASAN-USE-AFTER-FREE-WRITE] the chunk can be dropped testing without sub-chunk 3/5 disabling configs for [locking atomic_sleep hang memleak ubsan bug_or_warning], they are not needed testing commit fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 kernel signature: 9fb87496f734a258475e54f27fd1b637f6b623eb3def9a422542700ab0b5e92f run #0: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #1: crashed: KASAN: out-of-bounds Write in ext4_ext_remove_space run #2: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #3: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #4: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #5: crashed: KASAN: use-after-free Read in ext4_ext_remove_space run #6: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #7: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #8: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #9: crashed: KASAN: out-of-bounds Read in ext4_ext_insert_extent representative crash: KASAN: use-after-free Write in ext4_ext_remove_space, types: [KASAN-USE-AFTER-FREE-WRITE 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 fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 kernel signature: ef9fdbd8734fc5be53a6386e98aa48357441e1eef3a9dccffe0486f18a00d3a6 run #0: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #1: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #2: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #3: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #4: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #5: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #6: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #7: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #8: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #9: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent representative crash: KASAN: use-after-free Read in ext4_ext_insert_extent, types: [KASAN-USE-AFTER-FREE-READ KASAN-USE-AFTER-FREE-WRITE] the chunk can be dropped testing without sub-chunk 5/5 disabling configs for [hang memleak ubsan bug_or_warning locking atomic_sleep], they are not needed testing commit fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 failed building fc9aa81462ee32fea3dd6d7c6d8d7dcdb69637df: net/socket.c:1128:(.text+0x1307): undefined reference to `wext_handle_ioctl' net/socket.c:3397:(.text+0x17c7): undefined reference to `compat_wext_handle_ioctl' net/core/net-procfs.c:346:(.text+0x33b): undefined reference to `wext_proc_exit' net/core/net-procfs.c:330:(.text+0x4e2): undefined reference to `wext_proc_init' minimized to 46 configs; suspects: [HID_ZEROPLUS USB_NET_MCS7830 USB_NET_NET1080 USB_NET_PLUSB USB_NET_RNDIS_HOST USB_NET_SMSC75XX USB_NET_SMSC95XX USB_NET_SR9700 USB_NET_SR9800 USB_NET_ZAURUS USB_OHCI_HCD USB_OHCI_HCD_PCI USB_OHCI_HCD_PLATFORM USB_OTG USB_OTG_FSM USB_PRINTER USB_SERIAL USB_SERIAL_FTDI_SIO USB_SERIAL_GENERIC USB_SERIAL_PL2303 USB_STORAGE_ALAUDA USB_STORAGE_CYPRESS_ATACB USB_STORAGE_DATAFAB USB_STORAGE_FREECOM USB_STORAGE_ISD200 USB_STORAGE_JUMPSHOT USB_STORAGE_KARMA USB_STORAGE_ONETOUCH USB_STORAGE_SDDR09 USB_STORAGE_SDDR55 USB_STORAGE_USBAT USB_TRANCEVIBRATOR USB_U_AUDIO USB_U_ETHER USB_U_SERIAL USB_WDM USB_XHCI_PCI_RENESAS WLAN WLAN_VENDOR_ATH WLAN_VENDOR_ATMEL WLAN_VENDOR_BROADCOM WLAN_VENDOR_INTERSIL WLAN_VENDOR_MARVELL WLAN_VENDOR_MEDIATEK WLAN_VENDOR_MICROCHIP WLAN_VENDOR_RALINK WLAN_VENDOR_REALTEK WLAN_VENDOR_RSI WLAN_VENDOR_ZYDAS X86_X32 ZEROPLUS_FF] disabling configs for [bug_or_warning locking atomic_sleep hang memleak ubsan], they are not needed testing current HEAD e8b14e1cefe8a3049a46a48685bf937ca244949d testing commit e8b14e1cefe8a3049a46a48685bf937ca244949d gcc compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.44 kernel signature: 3e31f912a521d6549b73010ce1d66218d4cd7d6a5ef62bc63e4b3ea49bee1fcb run #0: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #1: crashed: KASAN: use-after-free Read in ext4_find_extent run #2: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #3: crashed: KASAN: use-after-free Write in ext4_ext_remove_space run #4: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #5: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #6: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #7: crashed: KASAN: use-after-free Read in ext4_ext_insert_extent run #8: crashed: KASAN: out-of-bounds Read in ext4_ext_remove_space run #9: crashed: invalid opcode in ext4_split_extent_at representative crash: KASAN: use-after-free Read in ext4_find_extent, types: [KASAN-USE-AFTER-FREE-READ KASAN-USE-AFTER-FREE-WRITE] crash still not fixed/happens on the oldest tested release revisions tested: 7, total time: 1h2m31.885063051s (build: 20m44.254048232s, test: 40m15.964767516s) crash still not fixed or there were kernel test errors commit msg: Merge 5.10.250 into android13-5.10-lts crash: KASAN: use-after-free Read in ext4_find_extent ================================================================== BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:826 [inline] BUG: KASAN: use-after-free in ext4_find_extent+0xb93/0xc70 fs/ext4/extents.c:945 Read of size 4 at addr ffff88812b428064 by task syz.6.18/539 CPU: 0 PID: 539 Comm: syz.6.18 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x81/0xac lib/dump_stack.c:118 print_address_description.constprop.0+0x24/0x160 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report.cold+0x82/0xdb mm/kasan/report.c:452 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_ext_binsearch fs/ext4/extents.c:826 [inline] ext4_find_extent+0xb93/0xc70 fs/ext4/extents.c:945 ext4_ext_map_blocks+0x16e/0x52d0 fs/ext4/extents.c:4160 ext4_map_blocks+0x58d/0x1430 fs/ext4/inode.c:674 _ext4_get_block+0x206/0x5b0 fs/ext4/inode.c:817 ext4_get_block+0x11/0x20 fs/ext4/inode.c:834 ext4_block_write_begin+0x3b9/0xdc0 fs/ext4/inode.c:1101 ext4_write_begin+0x484/0xf00 fs/ext4/inode.c:1243 ext4_da_write_begin+0x52b/0xc30 fs/ext4/inode.c:3033 generic_perform_write+0x202/0x4a0 mm/filemap.c:3509 ext4_buffered_write_iter+0x1e5/0x420 fs/ext4/file.c:271 ext4_file_write_iter+0x358/0x18e0 fs/ext4/file.c:685 call_write_iter include/linux/fs.h:2066 [inline] new_sync_write+0x358/0x6d0 fs/read_write.c:518 vfs_write+0x4e4/0x750 fs/read_write.c:605 ksys_write+0x111/0x210 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:667 do_syscall_64+0x32/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7ff94b4fb8f9 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:00007ff94af42028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ff94b72a080 RCX: 00007ff94b4fb8f9 RDX: 00000000002a979d RSI: 0000400000000000 RDI: 0000000000000004 RBP: 00007ff94b58d1bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff94b72a080 R15: 00007fff4f53d218 The buggy address belongs to the page: page:ffffea0004ad0a00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x12b428 flags: 0x4000000000000000() raw: 4000000000000000 dead000000000100 dead000000000122 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 0x8100dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO|0x8000000), pid 531, ts 60390570328, free_ts 60810028079 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page mm/page_alloc.c:2462 [inline] get_page_from_freelist+0x1fee/0x2ad0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x2ae/0x2530 mm/page_alloc.c:5370 __alloc_pages include/linux/gfp.h:544 [inline] __alloc_pages_node include/linux/gfp.h:557 [inline] alloc_pages_node include/linux/gfp.h:571 [inline] alloc_pages include/linux/gfp.h:590 [inline] do_anonymous_page mm/memory.c:3963 [inline] handle_pte_fault+0x1672/0x3210 mm/memory.c:4786 __handle_mm_fault+0xac7/0xfa0 mm/memory.c:4944 handle_mm_fault+0x1b8/0x6b0 mm/memory.c:5358 do_user_addr_fault+0x4d0/0xa20 arch/x86/mm/fault.c:1362 handle_page_fault arch/x86/mm/fault.c:1428 [inline] exc_page_fault+0x65/0xc0 arch/x86/mm/fault.c:1484 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:571 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1349 [inline] free_pcp_prepare+0x1a7/0x230 mm/page_alloc.c:1421 free_unref_page_prepare mm/page_alloc.c:3336 [inline] free_unref_page_list+0x18a/0xae0 mm/page_alloc.c:3443 release_pages+0x374/0xb00 mm/swap.c:1103 free_pages_and_swap_cache+0x180/0x1e0 mm/swap_state.c:356 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free mm/mmu_gather.c:240 [inline] tlb_flush_mmu mm/mmu_gather.c:247 [inline] tlb_finish_mmu+0x129/0x790 mm/mmu_gather.c:326 exit_mmap+0x296/0x520 mm/mmap.c:3387 __mmput kernel/fork.c:1153 [inline] mmput kernel/fork.c:1176 [inline] mmput+0x99/0x430 kernel/fork.c:1170 exit_mm kernel/exit.c:539 [inline] do_exit+0x873/0x2330 kernel/exit.c:859 do_group_exit+0xe6/0x290 kernel/exit.c:986 get_signal+0x353/0x1a10 kernel/signal.c:2793 arch_do_signal_or_restart+0x2ad/0x2510 arch/x86/kernel/signal.c:805 handle_signal_work kernel/entry/common.c:145 [inline] exit_to_user_mode_loop kernel/entry/common.c:169 [inline] exit_to_user_mode_prepare+0x10f/0x160 kernel/entry/common.c:199 syscall_exit_to_user_mode+0x27/0x160 kernel/entry/common.c:274 do_syscall_64+0x3f/0x80 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x61/0xcb Memory state around the buggy address: ffff88812b427f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88812b427f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88812b428000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88812b428080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88812b428100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== EXT4-fs error (device loop6): ext4_ext_split:1142: inode #17: comm syz.6.18: eh_entries 52628 != eh_max 38135! EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 92266986667916, count = 4975 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 35323286742919, count = 27942 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 105517886271260, count = 15862 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 61362341493597, count = 7955 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 37895144420410, count = 2314 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 41289220955298, count = 22581 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 59734439994028, count = 10345 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 39292901456645, count = 9442 EXT4-fs error (device loop6): ext4_free_blocks:5700: comm syz.6.18: Freeing blocks not in datazone - block = 43792131442501, count = 22894