ci2 starts bisection 2025-10-11 07:24:31.810529695 +0000 UTC m=+113070.588996272 bisecting fixing commit since 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c building syzkaller on 5d7e17caf7d0971d22446d8a81bcf1cd8c18a0dc ensuring issue is reproducible on original commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c testing commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 2c8730deac62bf7e391176513de8219a22c3aec87c2db50a78758b78c98528d4 all runs: crashed: KASAN: use-after-free Read in __ext4_check_dir_entry representative crash: KASAN: use-after-free Read in __ext4_check_dir_entry, types: [KASAN-USE-AFTER-FREE-READ] check whether we can drop unnecessary instrumentation disabling configs for [memleak ubsan bug_or_warning locking atomic_sleep hang], they are not needed testing commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 34a57c6e80d004303f5018c34dd807a449282fd3cb2611ed798ef57f7aa24710 all runs: crashed: KASAN: use-after-free Read in __ext4_check_dir_entry representative crash: KASAN: use-after-free Read in __ext4_check_dir_entry, types: [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=5186 full=6555 leaves diff=264 split chunks (needed=false): <264> split chunk #0 of len 264 into 5 parts testing without sub-chunk 1/5 disabling configs for [locking atomic_sleep hang memleak ubsan bug_or_warning], they are not needed testing commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 5878705c04c51eaf9a77345c667e3afb39d07541b97774328dfdbc100180391e all runs: crashed: KASAN: use-after-free Read in __ext4_check_dir_entry representative crash: KASAN: use-after-free Read in __ext4_check_dir_entry, types: [KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 2/5 disabling configs for [hang memleak ubsan bug_or_warning locking atomic_sleep], they are not needed testing commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 9546eef7e491c8c0fccec5485efe14bc0328124f689b8df387196f1cb6c91a13 all runs: crashed: KASAN: use-after-free Read in __ext4_check_dir_entry representative crash: KASAN: use-after-free Read in __ext4_check_dir_entry, types: [KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 3/5 disabling configs for [memleak ubsan bug_or_warning locking atomic_sleep hang], they are not needed testing commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 0d6146c5d59e292b9cc6794d33f5035226e22c23ef184acc63f5b33343c92af4 all runs: crashed: KASAN: use-after-free Read in __ext4_check_dir_entry representative crash: KASAN: use-after-free Read in __ext4_check_dir_entry, types: [KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 4/5 disabling configs for [memleak ubsan bug_or_warning locking atomic_sleep hang], they are not needed testing commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: 25875c2cde1fa94bcd1c342f5c4c4df78a7038b3efcf69e648020a4a44dde7a0 all runs: crashed: KASAN: use-after-free Read in __ext4_check_dir_entry representative crash: KASAN: use-after-free Read in __ext4_check_dir_entry, types: [KASAN-USE-AFTER-FREE-READ] the chunk can be dropped testing without sub-chunk 5/5 disabling configs for [memleak ubsan bug_or_warning locking atomic_sleep hang], they are not needed testing commit 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 failed building 47e5d7e917782dd01d2ddb37de9a37b33ab19a6c: ld.lld: error: undefined symbol: wext_proc_init ld.lld: error: undefined symbol: wext_proc_exit ld.lld: error: undefined symbol: wext_handle_ioctl ld.lld: error: undefined symbol: compat_wext_handle_ioctl minimized to 52 configs; suspects: [HID_ZEROPLUS USB_NET_CDC_MBIM USB_NET_CDC_SUBSET USB_NET_CDC_SUBSET_ENABLE USB_NET_DM9601 USB_NET_GL620A 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_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 V4L2_ASYNC V4L2_FWNODE VIDEO_CAMERA_SENSOR WLAN WLAN_VENDOR_ATH WLAN_VENDOR_ATMEL WLAN_VENDOR_BROADCOM WLAN_VENDOR_INTERSIL WLAN_VENDOR_MARVELL WLAN_VENDOR_MEDIATEK WLAN_VENDOR_MICROCHIP WLAN_VENDOR_PURELIFI WLAN_VENDOR_RALINK WLAN_VENDOR_REALTEK WLAN_VENDOR_RSI WLAN_VENDOR_SILABS WLAN_VENDOR_ZYDAS ZEROPLUS_FF] disabling configs for [locking atomic_sleep hang memleak ubsan bug_or_warning], they are not needed testing current HEAD 1729ceebf41a0eb7ab80f51af415a846b43e9f69 testing commit 1729ceebf41a0eb7ab80f51af415a846b43e9f69 gcc compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 kernel signature: d2f272f68e0872316a112b0c57452679573f27158cefd40c71f487635a1e4e34 all runs: crashed: KASAN: use-after-free Read in __ext4_check_dir_entry representative crash: KASAN: use-after-free Read in __ext4_check_dir_entry, types: [KASAN-USE-AFTER-FREE-READ] crash still not fixed/happens on the oldest tested release revisions tested: 7, total time: 1h59m17.374018203s (build: 1h10m4.184903453s, test: 43m13.617797865s) crash still not fixed or there were kernel test errors commit msg: UPSTREAM: soc: qcom: mdt_loader: Fix error return values in mdt_header_valid() crash: KASAN: use-after-free Read in __ext4_check_dir_entry EXT4-fs warning (device loop2): dx_probe:845: inode #2: comm syz.2.16: Hash code is SIPHASH, but hash not in dirent EXT4-fs warning (device loop2): dx_probe:966: inode #2: comm syz.2.16: Corrupt directory, running e2fsck is recommended ================================================================== BUG: KASAN: use-after-free in __ext4_check_dir_entry+0x442/0x670 fs/ext4/dir.c:85 Read of size 2 at addr ffff888124d68003 by task syz.2.16/446 CPU: 0 PID: 446 Comm: syz.2.16 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: __dump_stack+0x19/0x1c lib/dump_stack.c:88 dump_stack_lvl+0xa3/0xec lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report_generic.c:349 __ext4_check_dir_entry+0x442/0x670 fs/ext4/dir.c:85 ext4_readdir+0xbb6/0x31e0 fs/ext4/dir.c:261 iterate_dir+0x221/0x540 fs/readdir.c:-1 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0xc9/0x190 fs/readdir.c:354 __x64_sys_getdents64+0x76/0x80 fs/readdir.c:354 x64_sys_call+0x15c/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:218 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe8e358e929 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:00007fe8e431b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007fe8e37b5fa0 RCX: 00007fe8e358e929 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007fe8e3610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe8e37b5fa0 R15: 00007ffed349fed8 The buggy address belongs to the physical page: page:ffffea0004935a00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x124d68 flags: 0x4000000000000000(zone=1) raw: 4000000000000000 ffffea00049358c8 ffffea0004935a48 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 0x8140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO|__GFP_CMA), pid 398, tgid 398 (udevd), ts 58892675769, free_ts 58893691477 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook mm/page_alloc.c:2643 [inline] prep_new_page+0x58c/0x650 mm/page_alloc.c:2650 get_page_from_freelist+0x2f0f/0x2f80 mm/page_alloc.c:4554 __alloc_pages+0x1c3/0x450 mm/page_alloc.c:5868 __folio_alloc+0x12/0x40 mm/page_alloc.c:5900 __folio_alloc_node include/linux/gfp.h:245 [inline] folio_alloc include/linux/gfp.h:274 [inline] alloc_page_vma include/linux/gfp.h:283 [inline] do_anonymous_page mm/memory.c:4283 [inline] handle_pte_fault mm/memory.c:5169 [inline] __handle_mm_fault mm/memory.c:5313 [inline] handle_mm_fault+0x1006/0x1a80 mm/memory.c:5453 do_user_addr_fault+0x34b/0xa10 arch/x86/mm/fault.c:1374 handle_page_fault arch/x86/mm/fault.c:1466 [inline] exc_page_fault+0x51/0xb0 arch/x86/mm/fault.c:1522 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:608 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1551 [inline] free_pcp_prepare mm/page_alloc.c:1625 [inline] free_unref_page_prepare+0x645/0x650 mm/page_alloc.c:3589 free_unref_page_list+0x112/0x890 mm/page_alloc.c:3740 release_pages+0x904/0x960 mm/swap.c:1043 free_pages_and_swap_cache+0x66/0x80 mm/swap_state.c:315 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu mm/mmu_gather.c:261 [inline] tlb_finish_mmu+0x1af/0x380 mm/mmu_gather.c:361 unmap_region+0x290/0x2e0 mm/mmap.c:2418 do_mas_align_munmap+0x9b4/0xf60 mm/mmap.c:2691 do_mas_munmap+0x182/0x1f0 mm/mmap.c:2749 __vm_munmap+0x17f/0x290 mm/mmap.c:3048 __do_sys_munmap mm/mmap.c:3074 [inline] __se_sys_munmap mm/mmap.c:3070 [inline] __x64_sys_munmap+0x66/0x70 mm/mmap.c:3070 x64_sys_call+0x8a/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff888124d67f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888124d67f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888124d68000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888124d68080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888124d68100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== EXT4-fs error (device loop2): ext4_readdir:263: inode #2: block 255: comm syz.2.16: path (unknown): bad entry in directory: rec_len is smaller than minimal - offset=1023, inode=0, rec_len=0, size=1024 fake=0