syzbot


KASAN: use-after-free Read in __ocfs2_find_path

Status: upstream: reported C repro on 2024/10/09 20:34
Subsystems: ocfs2
[Documentation on labels]
Reported-by: syzbot+66c146268dc88f4341fd@syzkaller.appspotmail.com
First crash: 10d, last: 9d09h
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: general protection fault in ocfs2_shutdown_local_alloc (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ocfs2?] KASAN: use-after-free Read in __ocfs2_find_path 1 (3) 2024/10/10 04:32
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: use-after-free Read in __ocfs2_find_path C 7 10d 10d 0/3 upstream: reported C repro on 2024/10/05 20:46
linux-6.1 KASAN: use-after-free Read in __ocfs2_find_path C 3 8d16h 8d16h 0/3 upstream: reported C repro on 2024/10/07 07:25
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/10/10 04:09 20m lizhi.xu@windriver.com patch upstream OK log

Sample crash report:
loop0: detected capacity change from 0 to 32768
==================================================================
BUG: KASAN: use-after-free in __ocfs2_find_path+0x203/0x7e0 fs/ocfs2/alloc.c:1824
Read of size 4 at addr ffff8880707fb000 by task syz-executor231/5221

CPU: 1 UID: 0 PID: 5221 Comm: syz-executor231 Not tainted 6.12.0-rc1-syzkaller-00306-g27cc6fdf7201 #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:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 __ocfs2_find_path+0x203/0x7e0 fs/ocfs2/alloc.c:1824
 ocfs2_find_leaf+0xcf/0x230 fs/ocfs2/alloc.c:1938
 ocfs2_get_clusters_nocache+0x1ad/0xbf0 fs/ocfs2/extent_map.c:418
 ocfs2_get_clusters+0x5bd/0xbd0 fs/ocfs2/extent_map.c:621
 ocfs2_extent_map_get_blocks+0x24c/0x7d0 fs/ocfs2/extent_map.c:668
 ocfs2_read_virt_blocks+0x313/0xb20 fs/ocfs2/extent_map.c:983
 ocfs2_read_dir_block fs/ocfs2/dir.c:508 [inline]
 ocfs2_find_entry_el fs/ocfs2/dir.c:715 [inline]
 ocfs2_find_entry+0x43b/0x2780 fs/ocfs2/dir.c:1080
 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_get_system_file_inode fs/ocfs2/sysfile.c:136 [inline]
 ocfs2_get_system_file_inode+0x305/0x7b0 fs/ocfs2/sysfile.c:112
 ocfs2_init_global_system_inodes+0x32c/0x730 fs/ocfs2/super.c:457
 ocfs2_initialize_super fs/ocfs2/super.c:2248 [inline]
 ocfs2_fill_super+0x2f47/0x5750 fs/ocfs2/super.c:994
 mount_bdev+0x20a/0x2d0 fs/super.c:1679
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2b0 fs/super.c:1800
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4055 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
 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: 0033:0x7fdb53261dea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff04142618 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fff04142630 RCX: 00007fdb53261dea
RDX: 0000000020004440 RSI: 0000000020000780 RDI: 00007fff04142630
RBP: 0000000000000004 R08: 00007fff04142670 R09: 0000000000004444
R10: 0000000001000000 R11: 0000000000000282 R12: 0000000001000000
R13: 00007fff04142670 R14: 0000000000000003 R15: 0000000001000000
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x707fb
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001c1ff08 ffff8880b8744af0 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 11895450743, free_ts 13010080278
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 split_free_pages mm/page_alloc.c:6478 [inline]
 alloc_contig_range_noprof+0x821/0xe20 mm/page_alloc.c:6605
 __alloc_contig_pages mm/page_alloc.c:6634 [inline]
 alloc_contig_pages_noprof+0x4b3/0x5c0 mm/page_alloc.c:6714
 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+0x248/0x880 init/main.c:1269
 do_initcall_level+0x157/0x210 init/main.c:1331
 do_initcalls+0x3f/0x80 init/main.c:1347
 kernel_init_freeable+0x435/0x5d0 init/main.c:1580
 kernel_init+0x1d/0x2b0 init/main.c:1469
 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:1108 [inline]
 free_unref_page+0xcd0/0xf00 mm/page_alloc.c:2638
 free_contig_range+0x152/0x550 mm/page_alloc.c:6748
 destroy_args+0x8a/0x840 mm/debug_vm_pgtable.c:1017
 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1397
 do_one_initcall+0x248/0x880 init/main.c:1269
 do_initcall_level+0x157/0x210 init/main.c:1331
 do_initcalls+0x3f/0x80 init/main.c:1347
 kernel_init_freeable+0x435/0x5d0 init/main.c:1580
 kernel_init+0x1d/0x2b0 init/main.c:1469
 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:
 ffff8880707faf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880707faf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880707fb000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8880707fb080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880707fb100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (16):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/05 20:36 upstream 27cc6fdf7201 d7906eff .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_find_path
2024/10/06 10:48 upstream 8f602276d390 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 10:48 upstream 8f602276d390 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: use-after-free Read in __ocfs2_find_path
2024/10/05 20:30 upstream 27cc6fdf7201 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in __ocfs2_find_path
2024/10/05 20:30 upstream 27cc6fdf7201 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in __ocfs2_find_path
2024/10/05 21:33 upstream fc20a3e57247 d7906eff .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 14:34 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 80cb3fb61135 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 14:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 80cb3fb61135 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 10:19 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 80cb3fb61135 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 10:19 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 80cb3fb61135 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 04:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 9852d85ec9d4 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 03:16 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 9852d85ec9d4 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 01:47 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 9852d85ec9d4 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 01:47 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 9852d85ec9d4 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: use-after-free Read in __ocfs2_find_path
2024/10/06 06:34 upstream fc20a3e57247 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __ocfs2_find_path
2024/10/05 21:58 linux-next c02d24a5af66 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: out-of-bounds Read in __ocfs2_find_path
* Struck through repros no longer work on HEAD.