ci2 starts bisection 2025-11-23 10:26:50.173433267 +0000 UTC m=+142358.040152631
bisecting fixing commit since 5e1b899f19c3d900664c1ca05c4714c24647d82b
building syzkaller on cf25e2c2a28647d60ca5aa9f701d86de5207bc26
ensuring issue is reproducible on original commit 5e1b899f19c3d900664c1ca05c4714c24647d82b

testing commit 5e1b899f19c3d900664c1ca05c4714c24647d82b gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 1e11e529d2952bfe55c42a8a8f380041701a60b598c942c269c41836a8448481
run #0: crashed: KASAN: use-after-free Read in dx_insert_block
run #1: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #2: crashed: KASAN: use-after-free Read in dx_insert_block
run #3: crashed: KASAN: use-after-free Read in dx_insert_block
run #4: crashed: KASAN: use-after-free Read in ext4_htree_fill_tree
run #5: crashed: KASAN: use-after-free Read in dx_insert_block
run #6: crashed: KASAN: use-after-free Read in dx_insert_block
run #7: crashed: KASAN: use-after-free Read in dx_insert_block
run #8: crashed: KASAN: use-after-free Read in dx_insert_block
run #9: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #10: crashed: KASAN: use-after-free Read in dx_insert_block
run #11: crashed: KASAN: use-after-free Read in dx_insert_block
run #12: crashed: KASAN: use-after-free Read in dx_insert_block
run #13: OK
run #14: OK
run #15: OK
run #16: OK
run #17: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #18: crashed: KASAN: use-after-free Read in ext4_htree_fill_tree
run #19: OK
representative crash: KASAN: use-after-free Read in dx_insert_block, types: [KASAN-USE-AFTER-FREE-READ]
check whether we can drop unnecessary instrumentation
disabling configs for [atomic_sleep hang memleak ubsan bug_or_warning locking], they are not needed
testing commit 5e1b899f19c3d900664c1ca05c4714c24647d82b gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: a500caecc7a508dc68240c7af5ecf15e493a0fd0fb7d47569e1169126780397b
run #0: crashed: KASAN: use-after-free Read in dx_insert_block
run #1: crashed: KASAN: use-after-free Read in dx_insert_block
run #2: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #3: crashed: KASAN: use-after-free Read in dx_insert_block
run #4: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #5: crashed: KASAN: use-after-free Read in dx_insert_block
run #6: crashed: BUG: unable to handle kernel paging request in corrupted
run #7: crashed: KASAN: use-after-free Read in dx_insert_block
run #8: crashed: KASAN: use-after-free Read in dx_insert_block
run #9: OK
representative crash: KASAN: use-after-free Read in dx_insert_block, types: [KASAN-USE-AFTER-FREE-READ KASAN-READ]
the bug reproduces without the instrumentation
disabling configs for [ubsan bug_or_warning locking atomic_sleep hang memleak], they are not needed
kconfig minimization: base=4921 full=6216 leaves diff=255
split chunks (needed=false): <255>
split chunk #0 of len 255 into 5 parts
testing without sub-chunk 1/5
disabling configs for [hang memleak ubsan bug_or_warning locking atomic_sleep], they are not needed
testing commit 5e1b899f19c3d900664c1ca05c4714c24647d82b gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 9b2e0b8073e2dc9827d88a9d37e1ab0cd299cd0ea193c48d42b29d2e376b3b34
run #0: crashed: KASAN: use-after-free Read in dx_insert_block
run #1: crashed: KASAN: use-after-free Read in dx_insert_block
run #2: crashed: KASAN: use-after-free Read in dx_insert_block
run #3: crashed: KASAN: slab-out-of-bounds Read in ext4_htree_fill_tree
run #4: crashed: KASAN: use-after-free Read in dx_insert_block
run #5: crashed: KASAN: use-after-free Read in ext4_htree_fill_tree
run #6: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #7: crashed: KASAN: use-after-free Read in dx_insert_block
run #8: OK
run #9: OK
representative crash: KASAN: use-after-free Read in dx_insert_block, 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 5e1b899f19c3d900664c1ca05c4714c24647d82b gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 146831053bf11eedb731b608ee7ef6752cc1c2db31577f55759e38b357c68137
run #0: crashed: KASAN: use-after-free Read in dx_insert_block
run #1: crashed: KASAN: use-after-free Read in dx_insert_block
run #2: crashed: KASAN: use-after-free Read in dx_insert_block
run #3: crashed: KASAN: use-after-free Read in dx_insert_block
run #4: crashed: KASAN: use-after-free Read in dx_insert_block
run #5: crashed: KASAN: use-after-free Read in ext4_htree_fill_tree
run #6: OK
run #7: OK
run #8: OK
run #9: OK
representative crash: KASAN: use-after-free Read in dx_insert_block, types: [KASAN-USE-AFTER-FREE-READ]
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 5e1b899f19c3d900664c1ca05c4714c24647d82b gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 1563b846540df298d86640740685a1612e34aa0f078a7a125252451bf50a0c70
run #0: crashed: KASAN: use-after-free Read in dx_insert_block
run #1: crashed: KASAN: use-after-free Read in dx_insert_block
run #2: crashed: KASAN: use-after-free Read in dx_insert_block
run #3: crashed: KASAN: use-after-free Read in dx_insert_block
run #4: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
representative crash: KASAN: use-after-free Read in dx_insert_block, types: [KASAN-USE-AFTER-FREE-READ]
the chunk can be dropped
testing without sub-chunk 4/5
disabling configs for [locking atomic_sleep hang memleak ubsan bug_or_warning], they are not needed
testing commit 5e1b899f19c3d900664c1ca05c4714c24647d82b gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: e1db61562c179ebb981bc1b698ae26de49f8274b5c2304b1f9d19d647c479f7d
run #0: crashed: KASAN: use-after-free Read in dx_insert_block
run #1: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #2: crashed: KASAN: use-after-free Read in ext4_htree_fill_tree
run #3: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #4: crashed: KASAN: use-after-free Read in ext4_htree_fill_tree
run #5: crashed: KASAN: use-after-free Read in dx_insert_block
run #6: OK
run #7: OK
run #8: OK
run #9: OK
representative crash: KASAN: use-after-free Read in dx_insert_block, types: [KASAN-USE-AFTER-FREE-READ KASAN-READ]
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 5e1b899f19c3d900664c1ca05c4714c24647d82b gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
failed building 5e1b899f19c3d900664c1ca05c4714c24647d82b: net/socket.c:1191: undefined reference to `wext_handle_ioctl'
net/socket.c:3390: undefined reference to `compat_wext_handle_ioctl'
net/core/net-procfs.c:343: undefined reference to `wext_proc_exit'
net/core/net-procfs.c:327: undefined reference to `wext_proc_init'
minimized to 51 configs; suspects: [HID_ZEROPLUS USB_MON 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 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 [memleak ubsan bug_or_warning locking atomic_sleep hang], they are not needed
testing current HEAD 057fdbf6d3c79123ad58eb55aa2428b2d951b04d
testing commit 057fdbf6d3c79123ad58eb55aa2428b2d951b04d gcc
compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 8b33cf47fff92dbd041a14caa6b5244eaa3d99abd9488a1b26cc885229e62737
run #0: crashed: KASAN: use-after-free Read in dx_insert_block
run #1: crashed: KASAN: use-after-free Read in dx_insert_block
run #2: crashed: KASAN: use-after-free Read in dx_insert_block
run #3: crashed: KASAN: slab-out-of-bounds Read in dx_insert_block
run #4: crashed: KASAN: use-after-free Read in dx_insert_block
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
representative crash: KASAN: use-after-free Read in dx_insert_block, types: [KASAN-USE-AFTER-FREE-READ]
crash still not fixed/happens on the oldest tested release
revisions tested: 7, total time: 1h32m34.318136033s (build: 23m53.64196232s, test: 1h6m46.913354387s)
crash still not fixed or there were kernel test errors
commit msg: Merge 5.15.196 into android13-5.15-lts
crash: KASAN: use-after-free Read in dx_insert_block
==================================================================
BUG: KASAN: use-after-free in dx_insert_block.isra.0+0xa9/0x150 fs/ext4/namei.c:1387
Read of size 157024 at addr ffff88812c3e4028 by task syz.5.19/559

CPU: 0 PID: 559 Comm: syz.5.19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x38/0x49 lib/dump_stack.c:106
 print_address_description.constprop.0+0x24/0x160 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report.cold+0x82/0xdb mm/kasan/report.c:444
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x148/0x190 mm/kasan/generic.c:189
 memmove+0x24/0x60 mm/kasan/shadow.c:54
 dx_insert_block.isra.0+0xa9/0x150 fs/ext4/namei.c:1387
 do_split+0x13f4/0x21c0 fs/ext4/namei.c:2080
 make_indexed_dir+0xdf1/0x1250 fs/ext4/namei.c:2392
 ext4_add_entry+0xd94/0x11f0 fs/ext4/namei.c:2504
 __ext4_link+0x33b/0x4b0 fs/ext4/namei.c:3536
 ext4_link+0x1a1/0x240 fs/ext4/namei.c:3577
 vfs_link+0x54c/0xa50 fs/namei.c:4565
 do_linkat+0x359/0x580 fs/namei.c:4636
 __do_sys_link fs/namei.c:4670 [inline]
 __se_sys_link fs/namei.c:4668 [inline]
 __x64_sys_link+0x7d/0xa0 fs/namei.c:4668
 x64_sys_call+0x728/0x990 arch/x86/include/generated/asm/syscalls_64.h:87
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x33/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9d15925169
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:00007f9d15397038 EFLAGS: 00000246 ORIG_RAX: 0000000000000056
RAX: ffffffffffffffda RBX: 00007f9d15b3dfa0 RCX: 00007f9d15925169
RDX: 0000000000000000 RSI: 0000200000000bc0 RDI: 0000200000001240
RBP: 00007f9d159a62a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9d15b3dfa0 R15: 00007fff01c7d738
 </TASK>

The buggy address belongs to the page:
page:ffffea0004b0f900 refcount:3 mapcount:1 mapping:ffff888108fefa18 index:0x1 pfn:0x12c3e4
memcg:ffff888100232280
aops:def_blk_aops ino:700005
flags: 0x400000000032201e(referenced|uptodate|dirty|lru|private|mappedtodisk|unevictable|mlocked|zone=1)
raw: 400000000032201e ffff88810023d540 ffffea0004b0f988 ffff888108fefa18
raw: 0000000000000001 ffff888129c20f18 0000000300000000 ffff888100232280
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 444, ts 60004200626, free_ts 60002419309
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook mm/page_alloc.c:2605 [inline]
 prep_new_page+0x1a2/0x310 mm/page_alloc.c:2611
 get_page_from_freelist+0x1ce2/0x30a0 mm/page_alloc.c:4485
 __alloc_pages+0x300/0x2d50 mm/page_alloc.c:5808
 __alloc_pages_node include/linux/gfp.h:595 [inline]
 alloc_pages_node include/linux/gfp.h:609 [inline]
 alloc_pages include/linux/gfp.h:622 [inline]
 __page_cache_alloc include/linux/pagemap.h:305 [inline]
 page_cache_ra_unbounded+0x2f8/0x720 mm/readahead.c:227
 do_page_cache_ra mm/readahead.c:280 [inline]
 force_page_cache_ra+0x307/0x610 mm/readahead.c:312
 page_cache_sync_ra+0x32f/0x440 mm/readahead.c:590
 page_cache_sync_readahead include/linux/pagemap.h:831 [inline]
 filemap_get_pages+0x464/0x11d0 mm/filemap.c:2569
 filemap_read+0x301/0xa60 mm/filemap.c:2654
 generic_file_read_iter+0x293/0x4a0 mm/filemap.c:2814
 blkdev_read_iter+0xfe/0x190 block/fops.c:563
 call_read_iter include/linux/fs.h:2206 [inline]
 new_sync_read+0x353/0x6d0 fs/read_write.c:404
 vfs_read+0x34a/0x4b0 fs/read_write.c:485
 ksys_read+0x111/0x210 fs/read_write.c:623
 __do_sys_read fs/read_write.c:633 [inline]
 __se_sys_read fs/read_write.c:631 [inline]
 __x64_sys_read+0x6e/0xb0 fs/read_write.c:631
 x64_sys_call+0x982/0x990 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x33/0xb0 arch/x86/entry/common.c:80
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1472 [inline]
 free_pcp_prepare+0x1b6/0x4c0 mm/page_alloc.c:1544
 free_unref_page_prepare mm/page_alloc.c:3534 [inline]
 free_unref_page+0x84/0x760 mm/page_alloc.c:3616
 free_the_page mm/page_alloc.c:805 [inline]
 __free_pages+0xd7/0xf0 mm/page_alloc.c:5884
 __vunmap+0x4b7/0x7f0 mm/vmalloc.c:2660
 free_work+0x51/0x70 mm/vmalloc.c:97
 process_one_work+0x62c/0xec0 kernel/workqueue.c:2325
 worker_thread+0x48e/0xdb0 kernel/workqueue.c:2472
 kthread+0x324/0x3e0 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88812c3e4f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88812c3e4f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88812c3e5000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88812c3e5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff88812c3e5100: fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb
==================================================================
EXT4-fs error (device loop5): ext4_dx_csum_set:531: inode #2: comm syz.5.19: dir seems corrupt?  Run e2fsck -D.