[syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    13d88ac54ddd Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=121965ef680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12b40c7b680000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10f691ef680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9e81dc4903c2/disk-13d88ac5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f40fd7326b3f/vmlinux-13d88ac5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2f399cd6ff7d/bzImage-13d88ac5.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/8e127c645a04/mount_0.gz

The issue was bisected to:

commit f268eedddf3595e85f8883dc50aed29654785696
Author: Phillip Lougher <phillip@squashfs.org.uk>
Date:   Sat Jun 11 03:21:32 2022 +0000

    squashfs: extend "page actor" to handle missing pages

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1252b717680000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=1152b717680000
console output: https://syzkaller.appspot.com/x/log.txt?x=1652b717680000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com
Fixes: f268eedddf35 ("squashfs: extend "page actor" to handle missing pages")

SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
==================================================================
BUG: KASAN: slab-out-of-bounds in __readahead_batch include/linux/pagemap.h:1364 [inline]
BUG: KASAN: slab-out-of-bounds in squashfs_readahead+0x9a6/0x20d0 fs/squashfs/file.c:569
Write of size 8 at addr ffff88801e393648 by task syz-executor100/5067

CPU: 1 PID: 5067 Comm: syz-executor100 Not tainted 6.6.0-syzkaller-15156-g13d88ac54ddd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:475
 kasan_report+0x142/0x170 mm/kasan/report.c:588
 __readahead_batch include/linux/pagemap.h:1364 [inline]
 squashfs_readahead+0x9a6/0x20d0 fs/squashfs/file.c:569
 read_pages+0x183/0x830 mm/readahead.c:160
 page_cache_ra_unbounded+0x68e/0x7c0 mm/readahead.c:269
 page_cache_sync_readahead include/linux/pagemap.h:1266 [inline]
 filemap_get_pages+0x49c/0x2080 mm/filemap.c:2497
 filemap_read+0x42b/0x10b0 mm/filemap.c:2593
 __kernel_read+0x425/0x8b0 fs/read_write.c:428
 integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
 process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3624 [inline]
 path_openat+0x2893/0x3280 fs/namei.c:3779
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f0e73d6c5f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd516ff158 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0031656c69662f2e RCX: 00007f0e73d6c5f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 00007f0e73ddf610 R08: 0000000000000225 R09: 0000000000000000
R10: 00007ffd516ff020 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffd516ff328 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Allocated by task 5067:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:198 [inline]
 __do_kmalloc_node mm/slab_common.c:1007 [inline]
 __kmalloc+0xb9/0x230 mm/slab_common.c:1020
 kmalloc_array include/linux/slab.h:637 [inline]
 squashfs_readahead+0x30c/0x20d0 fs/squashfs/file.c:552
 read_pages+0x183/0x830 mm/readahead.c:160
 page_cache_ra_unbounded+0x68e/0x7c0 mm/readahead.c:269
 page_cache_sync_readahead include/linux/pagemap.h:1266 [inline]
 filemap_get_pages+0x49c/0x2080 mm/filemap.c:2497
 filemap_read+0x42b/0x10b0 mm/filemap.c:2593
 __kernel_read+0x425/0x8b0 fs/read_write.c:428
 integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
 process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3624 [inline]
 path_openat+0x2893/0x3280 fs/namei.c:3779
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff88801e393640
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes to the right of
 allocated 8-byte region [ffff88801e393640, ffff88801e393648)

The buggy address belongs to the physical page:
page:ffffea000078e4c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801e393230 pfn:0x1e393
anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888012c41280 0000000000000000 dead000000000001
raw: ffff88801e393230 0000000080660063 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, tgid 1 (swapper/0), ts 10649202635, free_ts 9358727270
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1544 [inline]
 get_page_from_freelist+0x339a/0x3530 mm/page_alloc.c:3312
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4568
 alloc_pages_mpol+0x3de/0x640 mm/mempolicy.c:2133
 alloc_slab_page+0x6a/0x160 mm/slub.c:1870
 allocate_slab mm/slub.c:2017 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2070
 ___slab_alloc+0xc85/0x1310 mm/slub.c:3223
 __slab_alloc mm/slub.c:3322 [inline]
 __slab_alloc_node mm/slub.c:3375 [inline]
 slab_alloc_node mm/slub.c:3468 [inline]
 __kmem_cache_alloc_node+0x21d/0x300 mm/slub.c:3517
 __do_kmalloc_node mm/slab_common.c:1006 [inline]
 __kmalloc_node_track_caller+0xa5/0x230 mm/slab_common.c:1027
 kstrdup+0x3a/0x70 mm/util.c:62
 __kernfs_new_node+0x9d/0x870 fs/kernfs/dir.c:611
 kernfs_new_node+0x99/0x170 fs/kernfs/dir.c:679
 kernfs_create_link+0xa5/0x1f0 fs/kernfs/symlink.c:39
 sysfs_do_create_link_sd+0x85/0x100 fs/sysfs/symlink.c:44
 device_create_sys_dev_entry+0x10f/0x170 drivers/base/core.c:3451
 device_add+0x8cf/0xd30 drivers/base/core.c:3595
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1137 [inline]
 free_unref_page_prepare+0x92a/0xa50 mm/page_alloc.c:2347
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
 vfree+0x186/0x2e0 mm/vmalloc.c:2842
 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:2763
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x90f/0x1400 kernel/workqueue.c:2703
 worker_thread+0xa5f/0xff0 kernel/workqueue.c:2784
 kthread+0x2d3/0x370 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Memory state around the buggy address:
 ffff88801e393500: 00 fc fc fc fc fa fc fc fc fc 05 fc fc fc fc 05
 ffff88801e393580: fc fc fc fc 00 fc fc fc fc 05 fc fc fc fc fa fc
>ffff88801e393600: fc fc fc 00 fc fc fc fc 00 fc fc fc fc 00 fc fc
                                              ^
 ffff88801e393680: fc fc 00 fc fc fc fc 00 fc fc fc fc 00 fc fc fc
 ffff88801e393700: fc 00 fc fc fc fc fb fc fc fc fc 00 fc fc fc fc
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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syzbot will keep track of this issue. See:
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
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If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in squashfs_readahead

SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
p: ffff888020f895a0, bs: 4096, bl: 12, mp: 1, start: 0, fe: 0, squashfs_readahead
general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 1 PID: 5475 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-15156-g13d88ac54ddd-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:squashfs_readahead+0x5a1/0x1dd0 fs/squashfs/file.c:572
Code: 89 84 24 10 01 00 00 42 80 3c 30 00 74 08 4c 89 ef e8 e3 06 8d ff 48 c1 2c 24 0c 49 8b 5d 00 48 83 c3 20 48 89 d8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 df e8 c0 06 8d ff 4c 8b 03 48 c7 c7 60
RSP: 0018:ffffc900052c6380 EFLAGS: 00010202
RAX: 0000000000000004 RBX: 0000000000000020 RCX: ffff888019ac0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900052c65b0 R08: ffffffff825dd62d R09: 1ffff92000a58c0c
R10: dffffc0000000000 R11: fffff52000a58c0d R12: ffffc900052c6998
R13: ffff888020f895a0 R14: dffffc0000000000 R15: ffffc900052c64e0
FS:  00007fc5c7f106c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005649916ab2e8 CR3: 00000000209b4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 read_pages+0x183/0x830 mm/readahead.c:160
 page_cache_ra_unbounded+0x68e/0x7c0 mm/readahead.c:269
 page_cache_sync_readahead include/linux/pagemap.h:1266 [inline]
 filemap_get_pages+0x49c/0x2080 mm/filemap.c:2497
 filemap_read+0x42b/0x10b0 mm/filemap.c:2593
 __kernel_read+0x425/0x8b0 fs/read_write.c:428
 integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
 process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3624 [inline]
 path_openat+0x2893/0x3280 fs/namei.c:3779
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fc5c727cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007fc5c7f100c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fc5c739bf80 RCX: 00007fc5c727cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 00007fc5c72c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fc5c739bf80 R15: 00007ffd8245e0c8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:squashfs_readahead+0x5a1/0x1dd0 fs/squashfs/file.c:572
Code: 89 84 24 10 01 00 00 42 80 3c 30 00 74 08 4c 89 ef e8 e3 06 8d ff 48 c1 2c 24 0c 49 8b 5d 00 48 83 c3 20 48 89 d8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 df e8 c0 06 8d ff 4c 8b 03 48 c7 c7 60
RSP: 0018:ffffc900052c6380 EFLAGS: 00010202
RAX: 0000000000000004 RBX: 0000000000000020 RCX: ffff888019ac0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900052c65b0 R08: ffffffff825dd62d R09: 1ffff92000a58c0c
R10: dffffc0000000000 R11: fffff52000a58c0d R12: ffffc900052c6998
R13: ffff888020f895a0 R14: dffffc0000000000 R15: ffffc900052c64e0
FS:  00007fc5c7f106c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005649916ab2e8 CR3: 00000000209b4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 84 24 10 01 00 00 	mov    %eax,0x110(%rsp)
   7:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
   c:	74 08                	je     0x16
   e:	4c 89 ef             	mov    %r13,%rdi
  11:	e8 e3 06 8d ff       	call   0xff8d06f9
  16:	48 c1 2c 24 0c       	shrq   $0xc,(%rsp)
  1b:	49 8b 5d 00          	mov    0x0(%r13),%rbx
  1f:	48 83 c3 20          	add    $0x20,%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 c0 06 8d ff       	call   0xff8d06f9
  39:	4c 8b 03             	mov    (%rbx),%r8
  3c:	48                   	rex.W
  3d:	c7                   	.byte 0xc7
  3e:	c7                   	(bad)
  3f:	60                   	(bad)


Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1407c024e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12723810e80000

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-out-of-bounds Write in squashfs_readahead

SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
p: ffff88801ea30b18, bs: 4096, bl: 12, mp: 1, start: 0, fe: 0, squashfs_readahead
p: ffff88801ea30b18, mp: 0, e: 0,isr: 0, start: 0, squashfs_readahead
==================================================================
BUG: KASAN: slab-out-of-bounds in __readahead_batch include/linux/pagemap.h:1364 [inline]
BUG: KASAN: slab-out-of-bounds in squashfs_readahead+0xa5a/0x1de0 fs/squashfs/file.c:574
Write of size 8 at addr ffff88801ea30b20 by task syz-executor.0/5481

CPU: 1 PID: 5481 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-15156-g13d88ac54ddd-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:475
 kasan_report+0x142/0x170 mm/kasan/report.c:588
 __readahead_batch include/linux/pagemap.h:1364 [inline]
 squashfs_readahead+0xa5a/0x1de0 fs/squashfs/file.c:574
 read_pages+0x183/0x830 mm/readahead.c:160
 page_cache_ra_unbounded+0x68e/0x7c0 mm/readahead.c:269
 page_cache_sync_readahead include/linux/pagemap.h:1266 [inline]
 filemap_get_pages+0x49c/0x2080 mm/filemap.c:2497
 filemap_read+0x42b/0x10b0 mm/filemap.c:2593
 __kernel_read+0x425/0x8b0 fs/read_write.c:428
 integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
 process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3624 [inline]
 path_openat+0x2893/0x3280 fs/namei.c:3779
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f57b767cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007f57b84070c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f57b779bf80 RCX: 00007f57b767cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 00007f57b76c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f57b779bf80 R15: 00007ffd5c197a58
 </TASK>

Allocated by task 5481:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:198 [inline]
 __do_kmalloc_node mm/slab_common.c:1007 [inline]
 __kmalloc+0xb9/0x230 mm/slab_common.c:1020
 kmalloc_array include/linux/slab.h:637 [inline]
 squashfs_readahead+0x2e8/0x1de0 fs/squashfs/file.c:552
 read_pages+0x183/0x830 mm/readahead.c:160
 page_cache_ra_unbounded+0x68e/0x7c0 mm/readahead.c:269
 page_cache_sync_readahead include/linux/pagemap.h:1266 [inline]
 filemap_get_pages+0x49c/0x2080 mm/filemap.c:2497
 filemap_read+0x42b/0x10b0 mm/filemap.c:2593
 __kernel_read+0x425/0x8b0 fs/read_write.c:428
 integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
 process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3624 [inline]
 path_openat+0x2893/0x3280 fs/namei.c:3779
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff88801ea30b18
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes to the right of
 allocated 8-byte region [ffff88801ea30b18, ffff88801ea30b20)

The buggy address belongs to the physical page:
page:ffffea00007a8c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1ea30
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888012c41280 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080660066 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY), pid 25, tgid 25 (kdevtmpfs), ts 8927536691, free_ts 8917015211
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1544 [inline]
 get_page_from_freelist+0x339a/0x3530 mm/page_alloc.c:3312
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4568
 alloc_pages_mpol+0x3de/0x640 mm/mempolicy.c:2133
 alloc_slab_page+0x6a/0x160 mm/slub.c:1870
 allocate_slab mm/slub.c:2017 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2070
 ___slab_alloc+0xc85/0x1310 mm/slub.c:3223
 __slab_alloc mm/slub.c:3322 [inline]
 __slab_alloc_node mm/slub.c:3375 [inline]
 slab_alloc_node mm/slub.c:3468 [inline]
 __kmem_cache_alloc_node+0x21d/0x300 mm/slub.c:3517
 __do_kmalloc_node mm/slab_common.c:1006 [inline]
 __kmalloc_node_track_caller+0xa5/0x230 mm/slab_common.c:1027
 kstrndup+0x41/0xb0 mm/util.c:108
 smk_parse_smack security/smack/smack_access.c:468 [inline]
 smk_import_entry+0x18d/0x610 security/smack/smack_access.c:563
 smk_fetch+0xdd/0x140 security/smack/smack_lsm.c:310
 smack_d_instantiate+0x74a/0xa50 security/smack/smack_lsm.c:3573
 security_d_instantiate+0x9b/0xf0 security/security.c:3799
 d_instantiate+0x55/0x90 fs/dcache.c:2033
 shmem_mknod+0x191/0x1c0 mm/shmem.c:3246
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1137 [inline]
 free_unref_page_prepare+0x92a/0xa50 mm/page_alloc.c:2347
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
 mm_free_pgd kernel/fork.c:803 [inline]
 __mmdrop+0xb8/0x3d0 kernel/fork.c:919
 free_bprm+0x144/0x330 fs/exec.c:1490
 kernel_execve+0x8f5/0xa10 fs/exec.c:2024
 call_usermodehelper_exec_async+0x233/0x370 kernel/umh.c:110
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Memory state around the buggy address:
 ffff88801ea30a00: 06 fc fc fc fc fb fc fc fc fc 00 fc fc fc fc fb
 ffff88801ea30a80: fc fc fc fc fb fc fc fc fc fb fc fc fc fc fa fc
>ffff88801ea30b00: fc fc fc 00 fc fc fc fc fb fc fc fc fc 06 fc fc
                               ^
 ffff88801ea30b80: fc fc 06 fc fc fc fc fb fc fc fc fc fb fc fc fc
 ffff88801ea30c00: fc fb fc fc fc fc fb fc fc fc fc 06 fc fc fc fc
==================================================================


Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=139741a7680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12214824e80000

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[Phillip Lougher]

On Sun, Nov 12, 2023 at 5:32 AM syzbot
<syzbot+604424eb051c2f696163@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    13d88ac54ddd Merge tag 'vfs-6.7.fsid' of git://git.kernel...
> git tree:       upstream
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=121965ef680000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
> dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12b40c7b680000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10f691ef680000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/9e81dc4903c2/disk-13d88ac5.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/f40fd7326b3f/vmlinux-13d88ac5.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/2f399cd6ff7d/bzImage-13d88ac5.xz
> mounted in repro: https://storage.googleapis.com/syzbot-assets/8e127c645a04/mount_0.gz
>
> The issue was bisected to:
>
> commit f268eedddf3595e85f8883dc50aed29654785696
> Author: Phillip Lougher <phillip@squashfs.org.uk>
> Date:   Sat Jun 11 03:21:32 2022 +0000
>
>     squashfs: extend "page actor" to handle missing pages

Fixed the issue, and will send a patch shortly.

Phillip

>
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1252b717680000
> final oops:     https://syzkaller.appspot.com/x/report.txt?x=1152b717680000
> console output: https://syzkaller.appspot.com/x/log.txt?x=1652b717680000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com
> Fixes: f268eedddf35 ("squashfs: extend "page actor" to handle missing pages")
>
> SQUASHFS error: Unable to read metadata cache entry [6fa]
> SQUASHFS error: Unable to read metadata cache entry [6fa]
> SQUASHFS error: Unable to read metadata cache entry [6fa]
> ==================================================================
> BUG: KASAN: slab-out-of-bounds in __readahead_batch include/linux/pagemap.h:1364 [inline]
> BUG: KASAN: slab-out-of-bounds in squashfs_readahead+0x9a6/0x20d0 fs/squashfs/file.c:569
> Write of size 8 at addr ffff88801e393648 by task syz-executor100/5067
>
> CPU: 1 PID: 5067 Comm: syz-executor100 Not tainted 6.6.0-syzkaller-15156-g13d88ac54ddd #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
> Call Trace:
>  <TASK>
>  __dump_stack lib/dump_stack.c:88 [inline]
>  dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
>  print_address_description mm/kasan/report.c:364 [inline]
>  print_report+0x163/0x540 mm/kasan/report.c:475
>  kasan_report+0x142/0x170 mm/kasan/report.c:588
>  __readahead_batch include/linux/pagemap.h:1364 [inline]
>  squashfs_readahead+0x9a6/0x20d0 fs/squashfs/file.c:569
>  read_pages+0x183/0x830 mm/readahead.c:160
>  page_cache_ra_unbounded+0x68e/0x7c0 mm/readahead.c:269
>  page_cache_sync_readahead include/linux/pagemap.h:1266 [inline]
>  filemap_get_pages+0x49c/0x2080 mm/filemap.c:2497
>  filemap_read+0x42b/0x10b0 mm/filemap.c:2593
>  __kernel_read+0x425/0x8b0 fs/read_write.c:428
>  integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
>  process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3624 [inline]
>  path_openat+0x2893/0x3280 fs/namei.c:3779
>  do_filp_open+0x234/0x490 fs/namei.c:3809
>  do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
>  do_sys_open fs/open.c:1455 [inline]
>  __do_sys_open fs/open.c:1463 [inline]
>  __se_sys_open fs/open.c:1459 [inline]
>  __x64_sys_open+0x225/0x270 fs/open.c:1459
>  do_syscall_x64 arch/x86/entry/common.c:51 [inline]
>  do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
> RIP: 0033:0x7f0e73d6c5f9
> Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 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 b8 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007ffd516ff158 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
> RAX: ffffffffffffffda RBX: 0031656c69662f2e RCX: 00007f0e73d6c5f9
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
> RBP: 00007f0e73ddf610 R08: 0000000000000225 R09: 0000000000000000
> R10: 00007ffd516ff020 R11: 0000000000000246 R12: 0000000000000001
> R13: 00007ffd516ff328 R14: 0000000000000001 R15: 0000000000000001
>  </TASK>
>
> Allocated by task 5067:
>  kasan_save_stack mm/kasan/common.c:45 [inline]
>  kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
>  ____kasan_kmalloc mm/kasan/common.c:374 [inline]
>  __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
>  kasan_kmalloc include/linux/kasan.h:198 [inline]
>  __do_kmalloc_node mm/slab_common.c:1007 [inline]
>  __kmalloc+0xb9/0x230 mm/slab_common.c:1020
>  kmalloc_array include/linux/slab.h:637 [inline]
>  squashfs_readahead+0x30c/0x20d0 fs/squashfs/file.c:552
>  read_pages+0x183/0x830 mm/readahead.c:160
>  page_cache_ra_unbounded+0x68e/0x7c0 mm/readahead.c:269
>  page_cache_sync_readahead include/linux/pagemap.h:1266 [inline]
>  filemap_get_pages+0x49c/0x2080 mm/filemap.c:2497
>  filemap_read+0x42b/0x10b0 mm/filemap.c:2593
>  __kernel_read+0x425/0x8b0 fs/read_write.c:428
>  integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
>  ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
>  ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
>  ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
>  ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
>  process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
>  ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
>  do_open fs/namei.c:3624 [inline]
>  path_openat+0x2893/0x3280 fs/namei.c:3779
>  do_filp_open+0x234/0x490 fs/namei.c:3809
>  do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
>  do_sys_open fs/open.c:1455 [inline]
>  __do_sys_open fs/open.c:1463 [inline]
>  __se_sys_open fs/open.c:1459 [inline]
>  __x64_sys_open+0x225/0x270 fs/open.c:1459
>  do_syscall_x64 arch/x86/entry/common.c:51 [inline]
>  do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
>  entry_SYSCALL_64_after_hwframe+0x63/0x6b
>
> The buggy address belongs to the object at ffff88801e393640
>  which belongs to the cache kmalloc-8 of size 8
> The buggy address is located 0 bytes to the right of
>  allocated 8-byte region [ffff88801e393640, ffff88801e393648)
>
> The buggy address belongs to the physical page:
> page:ffffea000078e4c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801e393230 pfn:0x1e393
> anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
> page_type: 0xffffffff()
> raw: 00fff00000000800 ffff888012c41280 0000000000000000 dead000000000001
> raw: ffff88801e393230 0000000080660063 00000001ffffffff 0000000000000000
> page dumped because: kasan: bad access detected
> page_owner tracks the page as allocated
> page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, tgid 1 (swapper/0), ts 10649202635, free_ts 9358727270
>  set_page_owner include/linux/page_owner.h:31 [inline]
>  post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1537
>  prep_new_page mm/page_alloc.c:1544 [inline]
>  get_page_from_freelist+0x339a/0x3530 mm/page_alloc.c:3312
>  __alloc_pages+0x255/0x670 mm/page_alloc.c:4568
>  alloc_pages_mpol+0x3de/0x640 mm/mempolicy.c:2133
>  alloc_slab_page+0x6a/0x160 mm/slub.c:1870
>  allocate_slab mm/slub.c:2017 [inline]
>  new_slab+0x84/0x2f0 mm/slub.c:2070
>  ___slab_alloc+0xc85/0x1310 mm/slub.c:3223
>  __slab_alloc mm/slub.c:3322 [inline]
>  __slab_alloc_node mm/slub.c:3375 [inline]
>  slab_alloc_node mm/slub.c:3468 [inline]
>  __kmem_cache_alloc_node+0x21d/0x300 mm/slub.c:3517
>  __do_kmalloc_node mm/slab_common.c:1006 [inline]
>  __kmalloc_node_track_caller+0xa5/0x230 mm/slab_common.c:1027
>  kstrdup+0x3a/0x70 mm/util.c:62
>  __kernfs_new_node+0x9d/0x870 fs/kernfs/dir.c:611
>  kernfs_new_node+0x99/0x170 fs/kernfs/dir.c:679
>  kernfs_create_link+0xa5/0x1f0 fs/kernfs/symlink.c:39
>  sysfs_do_create_link_sd+0x85/0x100 fs/sysfs/symlink.c:44
>  device_create_sys_dev_entry+0x10f/0x170 drivers/base/core.c:3451
>  device_add+0x8cf/0xd30 drivers/base/core.c:3595
> page last free stack trace:
>  reset_page_owner include/linux/page_owner.h:24 [inline]
>  free_pages_prepare mm/page_alloc.c:1137 [inline]
>  free_unref_page_prepare+0x92a/0xa50 mm/page_alloc.c:2347
>  free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
>  vfree+0x186/0x2e0 mm/vmalloc.c:2842
>  delayed_vfree_work+0x56/0x80 mm/vmalloc.c:2763
>  process_one_work kernel/workqueue.c:2630 [inline]
>  process_scheduled_works+0x90f/0x1400 kernel/workqueue.c:2703
>  worker_thread+0xa5f/0xff0 kernel/workqueue.c:2784
>  kthread+0x2d3/0x370 kernel/kthread.c:388
>  ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
>  ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
>
> Memory state around the buggy address:
>  ffff88801e393500: 00 fc fc fc fc fa fc fc fc fc 05 fc fc fc fc 05
>  ffff88801e393580: fc fc fc fc 00 fc fc fc fc 05 fc fc fc fc fa fc
> >ffff88801e393600: fc fc fc 00 fc fc fc fc 00 fc fc fc fc 00 fc fc
>                                               ^
>  ffff88801e393680: fc fc 00 fc fc fc fc 00 fc fc fc fc 00 fc fc fc
>  ffff88801e393700: fc 00 fc fc fc fc fb fc fc fc fc 00 fc fc fc fc
> ==================================================================
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
>
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
>

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in squashfs_page_actor_init_special

SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 0 PID: 5484 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-15156-g13d88ac54ddd-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:squashfs_page_actor_init_special+0x20e/0x4c0 fs/squashfs/page_actor.c:128
Code: 00 00 00 49 8d 6c 24 48 48 89 e8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 32 02 00 00 c7 45 00 00 00 00 00 4c 89 f8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ff e8 93 34 8c ff 49 8b 2f 48 83 c5 20
RSP: 0018:ffffc90004fce4f8 EFLAGS: 00010202
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffff888015ad3b80
RDX: ffff888015ad3b80 RSI: 0000000000000000 RDI: ffff888027646840
RBP: ffff888027646848 R08: ffffffff825ea873 R09: 1ffffffff21ba48f
R10: dffffc0000000000 R11: fffffbfff21ba490 R12: ffff888027646800
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000010
FS:  00007f7b9e9ea6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7b9dd0662e CR3: 0000000020cfe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 squashfs_readpage_block+0x62a/0xf60 fs/squashfs/file_direct.c:70
 squashfs_read_folio+0x569/0xed0 fs/squashfs/file.c:479
 filemap_read_folio+0x19c/0x770 mm/filemap.c:2323
 filemap_create_folio mm/filemap.c:2451 [inline]
 filemap_get_pages+0xdf7/0x2080 mm/filemap.c:2504
 filemap_read+0x42b/0x10b0 mm/filemap.c:2593
 __kernel_read+0x425/0x8b0 fs/read_write.c:428
 integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
 process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3624 [inline]
 path_openat+0x2893/0x3280 fs/namei.c:3779
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f7b9dc7cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007f7b9e9ea0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f7b9dd9bf80 RCX: 00007f7b9dc7cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 00007f7b9dcc847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7b9dd9bf80 R15: 00007fff0acb6118
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:squashfs_page_actor_init_special+0x20e/0x4c0 fs/squashfs/page_actor.c:128
Code: 00 00 00 49 8d 6c 24 48 48 89 e8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 32 02 00 00 c7 45 00 00 00 00 00 4c 89 f8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ff e8 93 34 8c ff 49 8b 2f 48 83 c5 20
RSP: 0018:ffffc90004fce4f8 EFLAGS: 00010202
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffff888015ad3b80
RDX: ffff888015ad3b80 RSI: 0000000000000000 RDI: ffff888027646840
RBP: ffff888027646848 R08: ffffffff825ea873 R09: 1ffffffff21ba48f
R10: dffffc0000000000 R11: fffffbfff21ba490 R12: ffff888027646800
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000010
FS:  00007f7b9e9ea6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555d54061950 CR3: 0000000020cfe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 49 8d             	add    %cl,-0x73(%rcx)
   5:	6c                   	insb   (%dx),%es:(%rdi)
   6:	24 48                	and    $0x48,%al
   8:	48 89 e8             	mov    %rbp,%rax
   b:	48 c1 e8 03          	shr    $0x3,%rax
   f:	42 0f b6 04 30       	movzbl (%rax,%r14,1),%eax
  14:	84 c0                	test   %al,%al
  16:	0f 85 32 02 00 00    	jne    0x24e
  1c:	c7 45 00 00 00 00 00 	movl   $0x0,0x0(%rbp)
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ff             	mov    %r15,%rdi
  34:	e8 93 34 8c ff       	call   0xff8c34cc
  39:	49 8b 2f             	mov    (%r15),%rbp
  3c:	48 83 c5 20          	add    $0x20,%rbp


Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=10ed2f97680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=17f132ff680000

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in squashfs_page_actor_init_special

SQUASHFS error: Failed to read block 0x6fc: -5
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
SQUASHFS error: Unable to read metadata cache entry [6fa]
general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 1 PID: 5484 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-15156-g13d88ac54ddd-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:squashfs_page_actor_init_special+0x20e/0x4c0 fs/squashfs/page_actor.c:128
Code: 00 00 00 49 8d 6c 24 48 48 89 e8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 32 02 00 00 c7 45 00 00 00 00 00 4c 89 f8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ff e8 73 34 8c ff 49 8b 2f 48 83 c5 20
RSP: 0018:ffffc9000504e4f8 EFLAGS: 00010202
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffff888023400000
RDX: ffff888023400000 RSI: 0000000000000000 RDI: ffff88801d0c0f40
RBP: ffff88801d0c0f48 R08: ffffffff825ea893 R09: 1ffffffff21ba48f
R10: dffffc0000000000 R11: fffffbfff21ba490 R12: ffff88801d0c0f00
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000010
FS:  00007f371f1fe6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562a2771d950 CR3: 0000000023dac000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 squashfs_readpage_block+0x659/0xf90 fs/squashfs/file_direct.c:73
 squashfs_read_folio+0x569/0xed0 fs/squashfs/file.c:479
 filemap_read_folio+0x19c/0x770 mm/filemap.c:2323
 filemap_create_folio mm/filemap.c:2451 [inline]
 filemap_get_pages+0xdf7/0x2080 mm/filemap.c:2504
 filemap_read+0x42b/0x10b0 mm/filemap.c:2593
 __kernel_read+0x425/0x8b0 fs/read_write.c:428
 integrity_kernel_read+0xb0/0xf0 security/integrity/iint.c:221
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline]
 ima_calc_file_hash+0xad1/0x1b30 security/integrity/ima/ima_crypto.c:573
 ima_collect_measurement+0x554/0xb30 security/integrity/ima/ima_api.c:290
 process_measurement+0x1373/0x21c0 security/integrity/ima/ima_main.c:359
 ima_file_check+0xf1/0x170 security/integrity/ima/ima_main.c:557
 do_open fs/namei.c:3624 [inline]
 path_openat+0x2893/0x3280 fs/namei.c:3779
 do_filp_open+0x234/0x490 fs/namei.c:3809
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440
 do_sys_open fs/open.c:1455 [inline]
 __do_sys_open fs/open.c:1463 [inline]
 __se_sys_open fs/open.c:1459 [inline]
 __x64_sys_open+0x225/0x270 fs/open.c:1459
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f371fe7cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007f371f1fe0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f371ff9bf80 RCX: 00007f371fe7cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 00007f371fec847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f371ff9bf80 R15: 00007fff173cbda8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:squashfs_page_actor_init_special+0x20e/0x4c0 fs/squashfs/page_actor.c:128
Code: 00 00 00 49 8d 6c 24 48 48 89 e8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 32 02 00 00 c7 45 00 00 00 00 00 4c 89 f8 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 ff e8 73 34 8c ff 49 8b 2f 48 83 c5 20
RSP: 0018:ffffc9000504e4f8 EFLAGS: 00010202
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffff888023400000
RDX: ffff888023400000 RSI: 0000000000000000 RDI: ffff88801d0c0f40
RBP: ffff88801d0c0f48 R08: ffffffff825ea893 R09: 1ffffffff21ba48f
R10: dffffc0000000000 R11: fffffbfff21ba490 R12: ffff88801d0c0f00
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000010
FS:  00007f371f1fe6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562a2771d950 CR3: 0000000023dac000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 49 8d             	add    %cl,-0x73(%rcx)
   5:	6c                   	insb   (%dx),%es:(%rdi)
   6:	24 48                	and    $0x48,%al
   8:	48 89 e8             	mov    %rbp,%rax
   b:	48 c1 e8 03          	shr    $0x3,%rax
   f:	42 0f b6 04 30       	movzbl (%rax,%r14,1),%eax
  14:	84 c0                	test   %al,%al
  16:	0f 85 32 02 00 00    	jne    0x24e
  1c:	c7 45 00 00 00 00 00 	movl   $0x0,0x0(%rbp)
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ff             	mov    %r15,%rdi
  34:	e8 73 34 8c ff       	call   0xff8c34ac
  39:	49 8b 2f             	mov    (%r15),%rbp
  3c:	48 83 c5 20          	add    $0x20,%rbp


Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1637eba8e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1139bf88e80000

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com

Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=150f2170e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12214020e80000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

fs/squashfs/inode.c:128:60: error: use of undeclared identifier 'sqsh_ino'


Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1566c75b680000

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com

Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=16f91eff680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10923b0f680000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com

Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=12dbf797680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=15986fdf680000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com

Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=137b0270e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1142f82f680000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com

Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=16dd2f97680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1258c947680000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [squashfs?] KASAN: slab-out-of-bounds Write in squashfs_readahead (2)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+604424eb051c2f696163@syzkaller.appspotmail.com

Tested on:

commit:         13d88ac5 Merge tag 'vfs-6.7.fsid' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1639ea50e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=604424eb051c2f696163
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10560014e80000

Note: testing is done by a robot and is best-effort only.