syzbot


KASAN: use-after-free Read in hfsplus_releasepage

Status: upstream: reported C repro on 2022/12/06 16:30
Reported-by: syzbot+220d2620d5b7f20282e4@syzkaller.appspotmail.com
First crash: 559d, last: 473d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 KASAN: use-after-free Read in hfsplus_releasepage hfsplus C error 2 549d 566d 0/1 upstream: reported C repro on 2022/11/29 13:07
linux-5.15 KASAN: use-after-free Read in hfsplus_releasepage C done 1 466d 466d 3/3 fixed on 2023/04/11 15:29
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2023/03/02 17:30 28m bisect fix linux-4.14.y job log (0) log
2023/01/30 22:55 23m bisect fix linux-4.14.y job log (0) log

Sample crash report:
IPVS: ftp: loaded support on port[0] = 21
==================================================================
BUG: KASAN: use-after-free in hfsplus_releasepage+0x457/0x4e0 fs/hfsplus/inode.c:92
Read of size 4 at addr ffff8880b36f8cb8 by task syz-executor216/7979

CPU: 0 PID: 7979 Comm: syz-executor216 Not tainted 4.14.300-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load4_noabort+0x68/0x70 mm/kasan/report.c:429
 hfsplus_releasepage+0x457/0x4e0 fs/hfsplus/inode.c:92
 try_to_release_page+0x143/0x1e0 mm/filemap.c:3243
 block_invalidatepage+0x258/0x2f0 fs/buffer.c:1573
 do_invalidatepage mm/truncate.c:124 [inline]
 truncate_complete_page mm/truncate.c:144 [inline]
 truncate_inode_page+0x212/0x2f0 mm/truncate.c:192
 truncate_inode_pages_range+0x1e0/0x13e0 mm/truncate.c:316
 hfsplus_evict_inode+0x16/0xc0 fs/hfsplus/super.c:167
 evict+0x2c8/0x700 fs/inode.c:554
 iput_final fs/inode.c:1523 [inline]
 iput+0x458/0x7e0 fs/inode.c:1550
 hfsplus_put_super+0x258/0x3d0 fs/hfsplus/super.c:301
 generic_shutdown_super+0x144/0x370 fs/super.c:446
 kill_block_super+0x95/0xe0 fs/super.c:1161
 deactivate_locked_super+0x6c/0xd0 fs/super.c:319
 deactivate_super+0x7f/0xa0 fs/super.c:350
 cleanup_mnt+0x186/0x2c0 fs/namespace.c:1183
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xa44/0x2850 kernel/exit.c:868
 do_group_exit+0x100/0x2e0 kernel/exit.c:965
 SYSC_exit_group kernel/exit.c:976 [inline]
 SyS_exit_group+0x19/0x20 kernel/exit.c:974
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3

Allocated by task 7979:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618
 kmalloc include/linux/slab.h:488 [inline]
 kzalloc include/linux/slab.h:661 [inline]
 hfsplus_btree_open+0x4d/0xff0 fs/hfsplus/btree.c:142
 hfsplus_fill_super+0x9ce/0x1850 fs/hfsplus/super.c:473
 mount_bdev+0x2b3/0x360 fs/super.c:1134
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2572 [inline]
 do_mount+0xe65/0x2a30 fs/namespace.c:2905
 SYSC_mount fs/namespace.c:3121 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3098
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3

Freed by task 7979:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xc9/0x250 mm/slab.c:3815
 hfsplus_btree_close+0x152/0x1d0 fs/hfsplus/btree.c:279
 hfsplus_put_super+0x208/0x3d0 fs/hfsplus/super.c:299
 generic_shutdown_super+0x144/0x370 fs/super.c:446
 kill_block_super+0x95/0xe0 fs/super.c:1161
 deactivate_locked_super+0x6c/0xd0 fs/super.c:319
 deactivate_super+0x7f/0xa0 fs/super.c:350
 cleanup_mnt+0x186/0x2c0 fs/namespace.c:1183
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xa44/0x2850 kernel/exit.c:868
 do_group_exit+0x100/0x2e0 kernel/exit.c:965
 SYSC_exit_group kernel/exit.c:976 [inline]
 SyS_exit_group+0x19/0x20 kernel/exit.c:974
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3

The buggy address belongs to the object at ffff8880b36f8c80
 which belongs to the cache kmalloc-4096 of size 4096
The buggy address is located 56 bytes inside of
 4096-byte region [ffff8880b36f8c80, ffff8880b36f9c80)
The buggy address belongs to the page:
page:ffffea0002cdbe00 count:1 mapcount:0 mapping:ffff8880b36f8c80 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffff8880b36f8c80 0000000000000000 0000000100000001
raw: ffffea0002ce88a0 ffffea00028685a0 ffff88813fe74dc0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880b36f8b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880b36f8c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880b36f8c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff8880b36f8d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880b36f8d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/06 16:30 linux-4.14.y 179ef7fe8677 045cbb84 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-4-14 KASAN: use-after-free Read in hfsplus_releasepage
2022/12/13 04:54 linux-4.14.y 65afe34ac33d 67be1ae7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 KASAN: use-after-free Read in hfsplus_releasepage
* Struck through repros no longer work on HEAD.