syzbot


KASAN: use-after-free Read in ocfs2_search_dirblock

Status: upstream: reported C repro on 2024/08/16 09:49
Subsystems: ocfs2
[Documentation on labels]
Reported-by: syzbot+b9704899e166798d57c9@syzkaller.appspotmail.com
Fix commit: ocfs2: fix directory entry check in ocfs2_search_dirblock()
Patched on: [ci-upstream-linux-next-kasan-gce-root], missing on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci-upstream-rust-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb]
First crash: 662d, last: 515d
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: KASAN: slab-out-of-bounds Read in ocfs2_find_entry (log)
Repro: C syz .config
  
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
2f27b215-a125-451f-a652-cfbcdc1a1b19 assessment-security 💥 KASAN: use-after-free Read in ocfs2_search_dirblock 2026/06/02 14:39 2026/06/02 14:39 2026/06/02 15:08 62fe15281f5011cd203d8845b8767b10e7443aa5 failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/04c8643fa003713b693a684294ea0220b0457f61" "-s" "bzImage" "compile_commands.json"]: exit status 2 Root cause: ld.lld: error: undefined symbol: wcslen * * Restart config... * * * General architecture-dependent options * Kprobes (KPROBES) [N/y/?] n Optimize very unlikely/likely branches (JUMP_LABEL) [Y/n/?] y Static key selftest (STATIC_KEYS_SELFTEST) [N/y/?] n Static call selftest (STATIC_CALL_SELFTEST) [N/y/?] n Enable seccomp to safely execute untrusted bytecode (SECCOMP) [Y/n/?] y Show seccomp filter cache status in /proc/pid/seccomp_cache (SECCOMP_CACHE_DEBUG) [N/y/?] n Stack Protector buffer overflow detection (STACKPROTECTOR) [Y/n/?] y Strong Stack Protector (STACKPROTECTOR_STRONG) [Y/n/?] y Link Time Optimization (LTO) > 1. None (LTO_NONE) choice[1]: 1 Use Clang's Control Flow Integrity (CFI) (CFI_CLANG) [N/y/?] (NEW) Error in reading or end of file. Number of bits to use for ASLR of mmap base address (ARCH_MMAP_RND_BITS) [28] 28 Number of bits to use for ASLR of mmap base address for compatible applications (ARCH_MMAP_RND_COMPAT_BITS) [8] 8 MMU page size > 1. 4KiB pages (PAGE_SIZE_4KB) choice[1]: 1 Provide system calls for 32-bit time_t (COMPAT_32BIT_TIME) [Y/n/?] y Use a virtually-mapped stack (VMAP_STACK) [Y/n/?] y Support for randomizing kernel stack offset on syscall entry (RANDOMIZE_KSTACK_OFFSET) [Y/n/?] y Default state of kernel stack offset randomization (RANDOMIZE_KSTACK_OFFSET_DEFAULT) [N/y/?] n Locking event counts collection (LOCK_EVENT_COUNTS) [N/y/?] n * * Memory initialization * Initialize kernel stack variables at function entry 1. no automatic stack variable initialization (weakest) (INIT_STACK_NONE) 2. pattern-init everything (strongest) (INIT_STACK_ALL_PATTERN) > 3. zero-init everything (strongest and safest) (INIT_STACK_ALL_ZERO) choice[1-3?]: 3 Enable heap memory zeroing on allocation by default (INIT_ON_ALLOC_DEFAULT_ON) [Y/n/?] y Enable heap memory zeroing on free by default (INIT_ON_FREE_DEFAULT_ON) [N/y/?] n Enable register zeroing on function exit (ZERO_CALL_USED_REGS) [N/y/?] (NEW) Error in reading or end of file. * * Kernel hardening options * Randomize layout of sensitive kernel structures > 1. Disable structure layout randomization (RANDSTRUCT_NONE) 2. Fully randomize structure layout (RANDSTRUCT_FULL) (NEW) choice[1-2?]: Error in reading or end of file. * * Compile-time checks and compiler options * Debug information 1. Disable debug information (DEBUG_INFO_NONE) 2. Rely on the toolchain's implicit default DWARF version (DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT) > 3. Generate DWARF Version 4 debuginfo (DEBUG_INFO_DWARF4) 4. Generate DWARF Version 5 debuginfo (DEBUG_INFO_DWARF5) choice[1-4?]: 3 Reduce debugging information (DEBUG_INFO_REDUCED) [N/y/?] n Compressed Debug information > 1. Don't compress debug information (DEBUG_INFO_COMPRESSED_NONE) 2. Compress debugging information with zlib (DEBUG_INFO_COMPRESSED_ZLIB) 3. Compress debugging information with zstd (DEBUG_INFO_COMPRESSED_ZSTD) (NEW) choice[1-3?]: Error in reading or end of file. Produce split debuginfo in .dwo files (DEBUG_INFO_SPLIT) [N/y/?] n Generate BTF type information (DEBUG_INFO_BTF) [N/y/?] n Provide GDB scripts for kernel debugging (GDB_SCRIPTS) [N/y/?] n Warn for stack frames larger than (FRAME_WARN) [2048] 2048 Strip assembler-generated symbols during link (STRIP_ASM_SYMS) [N/y/?] n Install uapi headers to usr/include (HEADERS_INSTALL) [N/y/?] n Make section mismatch errors non-fatal (SECTION_MISMATCH_WARN_ONLY) [Y/n/?] y Force all function address 64B aligned (DEBUG_FORCE_FUNCTION_ALIGN_64B) [N/y/?] n Generate vmlinux.map file when linking (VMLINUX_MAP) [N/y/?] n Force weak per-cpu definitions (DEBUG_FORCE_WEAK_PER_CPU) [N/y/?] n In file included from /app/workdir/cache/src/284e7ac1f9d8a53170d69bacc37048dc0e96c1a7/io_uring/io_uring.c:96: In file included from /app/workdir/cache/src/284e7ac1f9d8a53170d69bacc
130e2621-aab2-4d32-b384-558d0677c0f5 assessment-security 💥 KASAN: use-after-free Read in ocfs2_search_dirblock 2026/05/25 08:58 2026/05/25 08:58 2026/05/25 09:28 c69befb30ac10e158cc9d1557b508ee3f0eca1de failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/04c8643fa003713b693a684294ea0220b0457f61" "-s" "bzImage" "compile_commands.json"]: exit status 2 Root cause: ld.lld: error: undefined symbol: wcslen * * Restart config... * * * General architecture-dependent options * Kprobes (KPROBES) [N/y/?] n Optimize very unlikely/likely branches (JUMP_LABEL) [Y/n/?] y Static key selftest (STATIC_KEYS_SELFTEST) [N/y/?] n Static call selftest (STATIC_CALL_SELFTEST) [N/y/?] n Enable seccomp to safely execute untrusted bytecode (SECCOMP) [Y/n/?] y Show seccomp filter cache status in /proc/pid/seccomp_cache (SECCOMP_CACHE_DEBUG) [N/y/?] n Stack Protector buffer overflow detection (STACKPROTECTOR) [Y/n/?] y Strong Stack Protector (STACKPROTECTOR_STRONG) [Y/n/?] y Link Time Optimization (LTO) > 1. None (LTO_NONE) choice[1]: 1 Use Clang's Control Flow Integrity (CFI) (CFI_CLANG) [N/y/?] (NEW) Error in reading or end of file. Number of bits to use for ASLR of mmap base address (ARCH_MMAP_RND_BITS) [28] 28 Number of bits to use for ASLR of mmap base address for compatible applications (ARCH_MMAP_RND_COMPAT_BITS) [8] 8 MMU page size > 1. 4KiB pages (PAGE_SIZE_4KB) choice[1]: 1 Provide system calls for 32-bit time_t (COMPAT_32BIT_TIME) [Y/n/?] y Use a virtually-mapped stack (VMAP_STACK) [Y/n/?] y Support for randomizing kernel stack offset on syscall entry (RANDOMIZE_KSTACK_OFFSET) [Y/n/?] y Default state of kernel stack offset randomization (RANDOMIZE_KSTACK_OFFSET_DEFAULT) [N/y/?] n Locking event counts collection (LOCK_EVENT_COUNTS) [N/y/?] n * * Memory initialization * Initialize kernel stack variables at function entry 1. no automatic stack variable initialization (weakest) (INIT_STACK_NONE) 2. pattern-init everything (strongest) (INIT_STACK_ALL_PATTERN) > 3. zero-init everything (strongest and safest) (INIT_STACK_ALL_ZERO) choice[1-3?]: 3 Enable heap memory zeroing on allocation by default (INIT_ON_ALLOC_DEFAULT_ON) [Y/n/?] y Enable heap memory zeroing on free by default (INIT_ON_FREE_DEFAULT_ON) [N/y/?] n Enable register zeroing on function exit (ZERO_CALL_USED_REGS) [N/y/?] (NEW) Error in reading or end of file. * * Kernel hardening options * Randomize layout of sensitive kernel structures > 1. Disable structure layout randomization (RANDSTRUCT_NONE) 2. Fully randomize structure layout (RANDSTRUCT_FULL) (NEW) choice[1-2?]: Error in reading or end of file. * * Compile-time checks and compiler options * Debug information 1. Disable debug information (DEBUG_INFO_NONE) 2. Rely on the toolchain's implicit default DWARF version (DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT) > 3. Generate DWARF Version 4 debuginfo (DEBUG_INFO_DWARF4) 4. Generate DWARF Version 5 debuginfo (DEBUG_INFO_DWARF5) choice[1-4?]: 3 Reduce debugging information (DEBUG_INFO_REDUCED) [N/y/?] n Compressed Debug information > 1. Don't compress debug information (DEBUG_INFO_COMPRESSED_NONE) 2. Compress debugging information with zlib (DEBUG_INFO_COMPRESSED_ZLIB) 3. Compress debugging information with zstd (DEBUG_INFO_COMPRESSED_ZSTD) (NEW) choice[1-3?]: Error in reading or end of file. Produce split debuginfo in .dwo files (DEBUG_INFO_SPLIT) [N/y/?] n Generate BTF type information (DEBUG_INFO_BTF) [N/y/?] n Provide GDB scripts for kernel debugging (GDB_SCRIPTS) [N/y/?] n Warn for stack frames larger than (FRAME_WARN) [2048] 2048 Strip assembler-generated symbols during link (STRIP_ASM_SYMS) [N/y/?] n Install uapi headers to usr/include (HEADERS_INSTALL) [N/y/?] n Make section mismatch errors non-fatal (SECTION_MISMATCH_WARN_ONLY) [Y/n/?] y Force all function address 64B aligned (DEBUG_FORCE_FUNCTION_ALIGN_64B) [N/y/?] n Generate vmlinux.map file when linking (VMLINUX_MAP) [N/y/?] n Force weak per-cpu definitions (DEBUG_FORCE_WEAK_PER_CPU) [N/y/?] n In file included from /app/workdir/cache/src/1ff067437745d6f5969cce905c3d4807b7212c12/net/socket.c:108: In file included from /app/workdir/cache/src/1ff067437745d6f5969cce905c3d480
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ocfs2?] KASAN: use-after-free Read in ocfs2_search_dirblock 0 (2) 2024/11/19 16:28
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: use-after-free Read in ocfs2_search_dirblock 19 C done 8 460d 490d 3/3 fixed on 2025/04/11 04:43
linux-6.1 KASAN: use-after-free Read in ocfs2_search_dirblock origin:lts-only 19 C inconclusive 2 503d 503d 0/3 upstream: reported C repro on 2025/01/21 15:12
Last patch testing requests (7)
Created Duration User Patch Repo Result
2024/11/19 16:28 19m dmantipov@yandex.ru patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 158f238aa69d91ad74e535c73f552bd4b025109c OK log
2024/11/08 07:51 13m retest repro upstream report log
2024/11/08 07:51 13m retest repro upstream report log
2024/11/08 07:51 13m retest repro upstream report log
2024/08/30 05:29 18m retest repro upstream report log
2024/08/30 05:29 18m retest repro upstream report log
2024/08/30 05:29 18m retest repro upstream report log

Sample crash report:
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
==================================================================
BUG: KASAN: use-after-free in ocfs2_match fs/ocfs2/dir.c:334 [inline]
BUG: KASAN: use-after-free in ocfs2_search_dirblock+0x26b/0x820 fs/ocfs2/dir.c:367
Read of size 1 at addr ffff8880710858cb by task syz-executor292/5841

CPU: 0 UID: 0 PID: 5841 Comm: syz-executor292 Not tainted 6.12.0-syzkaller-10740-g509f806f7f70 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 ocfs2_match fs/ocfs2/dir.c:334 [inline]
 ocfs2_search_dirblock+0x26b/0x820 fs/ocfs2/dir.c:367
 ocfs2_find_entry_id fs/ocfs2/dir.c:414 [inline]
 ocfs2_find_entry+0x1169/0x2730 fs/ocfs2/dir.c:1078
 ocfs2_find_files_on_disk+0xff/0x360 fs/ocfs2/dir.c:1981
 ocfs2_lookup_ino_from_name+0xb1/0x1e0 fs/ocfs2/dir.c:2003
 ocfs2_lookup+0x292/0xa30 fs/ocfs2/namei.c:122
 lookup_open fs/namei.c:3627 [inline]
 open_last_lookups fs/namei.c:3748 [inline]
 path_openat+0x11a7/0x3590 fs/namei.c:3984
 do_filp_open+0x27f/0x4e0 fs/namei.c:4014
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_open fs/open.c:1425 [inline]
 __se_sys_open fs/open.c:1421 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1421
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f45aff47a59
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 18 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f45afefe218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f45affd36a8 RCX: 00007f45aff47a59
RDX: 0000000000000000 RSI: 0000000400141042 RDI: 0000000020000080
RBP: 00007f45affd36a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f45aff9c0c0
R13: 0000000400141042 R14: 00007f45aff9c200 R15: 0031656c69662f2e
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x71085
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001c42188 ffffea0001c42108 0000000000000000
raw: 0000000000000000 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 0x8(__GFP_MOVABLE), pid 1, tgid 1 (swapper/0), ts 16694661071, free_ts 17832813418
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556
 split_free_pages mm/page_alloc.c:6360 [inline]
 alloc_contig_range_noprof+0x821/0xe00 mm/page_alloc.c:6487
 __alloc_contig_pages mm/page_alloc.c:6516 [inline]
 alloc_contig_pages_noprof+0x4b3/0x5c0 mm/page_alloc.c:6596
 debug_vm_pgtable_alloc_huge_page+0xaf/0x100 mm/debug_vm_pgtable.c:1084
 init_args+0x83b/0xb20 mm/debug_vm_pgtable.c:1266
 debug_vm_pgtable+0xe0/0x550 mm/debug_vm_pgtable.c:1304
 do_one_initcall+0x248/0x870 init/main.c:1266
 do_initcall_level+0x157/0x210 init/main.c:1328
 do_initcalls+0x3f/0x80 init/main.c:1344
 kernel_init_freeable+0x435/0x5d0 init/main.c:1577
 kernel_init+0x1d/0x2b0 init/main.c:1466
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xde3/0x1130 mm/page_alloc.c:2657
 free_contig_range+0x152/0x550 mm/page_alloc.c:6630
 destroy_args+0x92/0x910 mm/debug_vm_pgtable.c:1017
 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1397
 do_one_initcall+0x248/0x870 init/main.c:1266
 do_initcall_level+0x157/0x210 init/main.c:1328
 do_initcalls+0x3f/0x80 init/main.c:1344
 kernel_init_freeable+0x435/0x5d0 init/main.c:1577
 kernel_init+0x1d/0x2b0 init/main.c:1466
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff888071085780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888071085800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888071085880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff888071085900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888071085980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (14):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/30 02:20 upstream 509f806f7f70 68914665 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs KASAN: use-after-free Read in ocfs2_search_dirblock
2024/08/16 03:58 upstream d7a5aa4b3c00 e4bacdaf .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root KASAN: use-after-free Read in ocfs2_search_dirblock
2024/11/28 15:16 linux-next f486c8aa16b8 5df23865 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in ocfs2_search_dirblock
2024/08/16 05:29 upstream d7a5aa4b3c00 e4bacdaf .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root KASAN: slab-out-of-bounds Read in ocfs2_search_dirblock
2024/08/16 04:45 upstream d7a5aa4b3c00 e4bacdaf .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root KASAN: slab-out-of-bounds Read in ocfs2_search_dirblock
2025/01/09 20:06 upstream eea6e4b4dfb8 9220929f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: use-after-free Read in ocfs2_search_dirblock
2024/12/01 03:52 upstream d8b78066f4c9 68914665 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: use-after-free Read in ocfs2_search_dirblock
2024/10/04 12:33 upstream 3840cbe24cf0 d7906eff .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: use-after-free Read in ocfs2_search_dirblock
2024/08/16 03:04 upstream d7a5aa4b3c00 e4bacdaf .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: use-after-free Read in ocfs2_search_dirblock
2024/11/28 14:27 linux-next f486c8aa16b8 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in ocfs2_search_dirblock
2025/01/03 01:49 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 573067a5a685 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in ocfs2_search_dirblock
2024/12/28 03:37 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 573067a5a685 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in ocfs2_search_dirblock
2024/12/22 05:10 upstream 48f506ad0b68 d7f584ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-use-after-free Read in ocfs2_search_dirblock
2024/12/20 19:49 upstream 8faabc041a00 49cfeac8 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: slab-out-of-bounds Read in ocfs2_search_dirblock
* Struck through repros no longer work on HEAD.