syzbot


KASAN: slab-out-of-bounds Read in poly1305_update_arch

Status: upstream: reported C repro on 2024/05/06 14:58
Subsystems: bcachefs
[Documentation on labels]
Reported-by: syzbot+9375e47164f8e9588f17@syzkaller.appspotmail.com
First crash: 44d, last: 8d10h
Cause bisection: introduced by (bisect log) :
commit 03ef80b469d5d83530ce1ce15be78a40e5300f9b
Author: Kent Overstreet <kent.overstreet@linux.dev>
Date: Sat Sep 23 22:41:51 2023 +0000

  bcachefs: Ignore unknown mount options

Crash: KASAN: slab-out-of-bounds Read in poly1305_update_arch (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [crypto?] KASAN: slab-out-of-bounds Read in poly1305_update_arch 0 (1) 2024/05/06 14:58
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/06/08 05:28 17m retest repro upstream report log
2024/06/08 04:27 11m retest repro upstream report log

Sample crash report:
netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
loop0: detected capacity change from 0 to 32768
bcachefs (loop0): mounting version 1.7: mi_btree_bitmap opts=metadata_checksum=none,data_checksum=none,nojournal_transaction_names
bcachefs (loop0): recovering from clean shutdown, journal seq 10
==================================================================
BUG: KASAN: slab-out-of-bounds in poly1305_update_arch+0x259/0x7d0 arch/x86/crypto/poly1305_glue.c:198
Read of size 8 at addr ffff8880711a1790 by task syz-executor587/5067

CPU: 0 PID: 5067 Comm: syz-executor587 Not tainted 6.9.0-rc6-syzkaller-00234-g7367539ad4b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 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
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
 poly1305_update_arch+0x259/0x7d0 arch/x86/crypto/poly1305_glue.c:198
 crypto_poly1305_update+0x28/0x40 arch/x86/crypto/poly1305_glue.c:230
 bch2_checksum+0x5a9/0x730 fs/bcachefs/checksum.c:228
 bch2_btree_node_read_done+0x109a/0x5a40 fs/bcachefs/btree_io.c:1096
 btree_node_read_work+0x665/0x1300 fs/bcachefs/btree_io.c:1324
 bch2_btree_node_read+0x2b64/0x32c0
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1748 [inline]
 bch2_btree_root_read+0x61e/0x970 fs/bcachefs/btree_io.c:1772
 read_btree_roots+0x22d/0x7b0 fs/bcachefs/recovery.c:457
 bch2_fs_recovery+0x431c/0x6390 fs/bcachefs/recovery.c:785
 bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1043
 bch2_fs_open+0xa8d/0xdf0 fs/bcachefs/super.c:2102
 bch2_mount+0x71d/0x1320 fs/bcachefs/fs.c:1903
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2a0 fs/super.c:1779
 do_new_mount+0x2be/0xb40 fs/namespace.c:3352
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fed59dce66a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 1e 09 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:00007ffd6d591b08 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffd6d591b20 RCX: 00007fed59dce66a
RDX: 0000000020011a00 RSI: 0000000020011a40 RDI: 00007ffd6d591b20
RBP: 0000000000000004 R08: 00007ffd6d591b60 R09: 00000000000119f3
R10: 0000000001200014 R11: 0000000000000282 R12: 0000000001200014
R13: 00007ffd6d591b60 R14: 0000000000000003 R15: 0000000001000000
 </TASK>

Allocated by task 5066:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slub.c:3966 [inline]
 __kmalloc+0x233/0x4a0 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 security_inode_getattr+0xd8/0x130 security/security.c:2269
 vfs_getattr+0x45/0x430 fs/stat.c:173
 vfs_statx+0x1a5/0x4e0 fs/stat.c:248
 vfs_fstatat+0x135/0x190 fs/stat.c:304
 __do_sys_newfstatat fs/stat.c:468 [inline]
 __se_sys_newfstatat fs/stat.c:462 [inline]
 __x64_sys_newfstatat+0x117/0x190 fs/stat.c:462
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5066:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2106 [inline]
 slab_free mm/slub.c:4280 [inline]
 kfree+0x153/0x3a0 mm/slub.c:4390
 tomoyo_realpath_from_path+0x5a9/0x5e0 security/tomoyo/realpath.c:286
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 security_inode_getattr+0xd8/0x130 security/security.c:2269
 vfs_getattr+0x45/0x430 fs/stat.c:173
 vfs_statx+0x1a5/0x4e0 fs/stat.c:248
 vfs_fstatat+0x135/0x190 fs/stat.c:304
 __do_sys_newfstatat fs/stat.c:468 [inline]
 __se_sys_newfstatat fs/stat.c:462 [inline]
 __x64_sys_newfstatat+0x117/0x190 fs/stat.c:462
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880711a0000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1936 bytes to the right of
 allocated 4096-byte region [ffff8880711a0000, ffff8880711a1000)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x711a0
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888015042140 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
head: 00fff00000000840 ffff888015042140 dead000000000122 0000000000000000
head: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
head: 00fff00000000003 ffffea0001c46801 dead000000000122 00000000ffffffff
head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5066, tgid 536082784 (udevd), ts 5066, free_ts 15045477140
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page+0x5f/0x160 mm/slub.c:2175
 allocate_slab mm/slub.c:2338 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2391
 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525
 __slab_alloc mm/slub.c:3610 [inline]
 __slab_alloc_node mm/slub.c:3663 [inline]
 slab_alloc_node mm/slub.c:3835 [inline]
 __do_kmalloc_node mm/slub.c:3965 [inline]
 __kmalloc+0x2e5/0x4a0 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 security_inode_getattr+0xd8/0x130 security/security.c:2269
 vfs_getattr+0x45/0x430 fs/stat.c:173
 vfs_statx+0x1a5/0x4e0 fs/stat.c:248
 vfs_fstatat+0x135/0x190 fs/stat.c:304
 __do_sys_newfstatat fs/stat.c:468 [inline]
 __se_sys_newfstatat fs/stat.c:462 [inline]
 __x64_sys_newfstatat+0x117/0x190 fs/stat.c:462
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
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:1141 [inline]
 free_unref_page_prepare+0x97b/0xaa0 mm/page_alloc.c:2347
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
 free_contig_range+0x9e/0x160 mm/page_alloc.c:6572
 destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1036
 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1416
 do_one_initcall+0x248/0x880 init/main.c:1245
 do_initcall_level+0x157/0x210 init/main.c:1307
 do_initcalls+0x3f/0x80 init/main.c:1323
 kernel_init_freeable+0x435/0x5d0 init/main.c:1555
 kernel_init+0x1d/0x2b0 init/main.c:1444
 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:
 ffff8880711a1680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880711a1700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880711a1780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff8880711a1800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880711a1880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/05 01:01 upstream 7367539ad4b0 610f2a54 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs KASAN: slab-out-of-bounds Read in poly1305_update_arch
2024/05/04 22:19 upstream 7367539ad4b0 610f2a54 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root KASAN: use-after-free Read in poly1305_update_arch
2024/06/10 02:26 upstream 771ed66105de 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-out-of-bounds Read in poly1305_update_arch
2024/05/04 21:40 upstream 7367539ad4b0 610f2a54 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: slab-out-of-bounds Read in poly1305_update_arch
2024/05/25 03:50 upstream 02c438bbfffe a10a183e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in poly1305_update_arch
2024/05/23 04:08 upstream b6394d6f7159 4d098039 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in poly1305_update_arch
2024/05/09 05:39 linux-next e7b4ef8fffac 20bf80e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in poly1305_update_arch
* Struck through repros no longer work on HEAD.