Message-ID: <000000000000f075b9061520cbbe@google.com>
Date: Tue, 02 Apr 2024 10:54:24 -0700
From: syzbot <syzbot+4139435cb1b34cf759c2@...kaller.appspotmail.com>
To: amir73il@...il.com, brauner@...nel.org, chuck.lever@...cle.com, 
	jack@...e.cz, jlayton@...nel.org, linux-fsdevel@...r.kernel.org, 
	linux-kernel@...r.kernel.org, linux-nfs@...r.kernel.org, 
	syzkaller-bugs@...glegroups.com, viro@...iv.linux.org.uk
Subject: [syzbot] [nfs?] KASAN: slab-out-of-bounds Write in do_handle_open

Hello,

syzbot found the following issue on:

HEAD commit:    c0b832517f62 Add linux-next specific files for 20240402
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=148b0003180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=afcaf46d374cec8c
dashboard link: https://syzkaller.appspot.com/bug?extid=4139435cb1b34cf759c2
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=1547f529180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11e22f0d180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0d36ec76edc7/disk-c0b83251.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6f9bb4e37dd0/vmlinux-c0b83251.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2349287b14b7/bzImage-c0b83251.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4139435cb1b34cf759c2@...kaller.appspotmail.com

==================================================================
BUG: KASAN: slab-out-of-bounds in instrument_copy_from_user_before include/linux/instrumented.h:129 [inline]
BUG: KASAN: slab-out-of-bounds in _copy_from_user+0x7b/0xe0 lib/usercopy.c:22
Write of size 36 at addr ffff8880203f2e88 by task syz-executor205/5086

CPU: 1 PID: 5086 Comm: syz-executor205 Not tainted 6.9.0-rc2-next-20240402-syzkaller #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
 instrument_copy_from_user_before include/linux/instrumented.h:129 [inline]
 _copy_from_user+0x7b/0xe0 lib/usercopy.c:22
 copy_from_user include/linux/uaccess.h:183 [inline]
 handle_to_path fs/fhandle.c:203 [inline]
 do_handle_open+0x204/0x660 fs/fhandle.c:226
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a
RIP: 0033:0x7f81f2e5f269
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 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:00007ffcde6f13c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000130
RAX: ffffffffffffffda RBX: 00007ffcde6f15a8 RCX: 00007f81f2e5f269
RDX: 0000000000000000 RSI: 00000000200091c0 RDI: 00000000ffffffff
RBP: 00007f81f2ed2610 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffcde6f1598 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Allocated by task 5086:
 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:4048 [inline]
 __kmalloc_noprof+0x200/0x410 mm/slub.c:4061
 kmalloc_noprof include/linux/slab.h:664 [inline]
 handle_to_path fs/fhandle.c:195 [inline]
 do_handle_open+0x162/0x660 fs/fhandle.c:226
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

The buggy address belongs to the object at ffff8880203f2e80
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 8 bytes inside of
 allocated 36-byte region [ffff8880203f2e80, ffff8880203f2ea4)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x203f2
ksm flags: 0xfff80000000000(node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffefff(slab)
raw: 00fff80000000000 ffff888015041640 ffffea0000869bc0 dead000000000003
raw: 0000000000000000 0000000080200020 00000001ffffefff 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 4542, tgid -909298647 (udevd), ts 4542, free_ts 33444169271
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1490
 prep_new_page mm/page_alloc.c:1498 [inline]
 get_page_from_freelist+0x2e7e/0x2f40 mm/page_alloc.c:3454
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4712
 __alloc_pages_node_noprof include/linux/gfp.h:244 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:271 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2249
 allocate_slab+0x5a/0x2e0 mm/slub.c:2412
 new_slab mm/slub.c:2465 [inline]
 ___slab_alloc+0xea8/0x1430 mm/slub.c:3599
 __slab_alloc+0x58/0xa0 mm/slub.c:3684
 __slab_alloc_node mm/slub.c:3737 [inline]
 slab_alloc_node mm/slub.c:3915 [inline]
 __do_kmalloc_node mm/slub.c:4047 [inline]
 __kmalloc_noprof+0x25e/0x410 mm/slub.c:4061
 kmalloc_noprof include/linux/slab.h:664 [inline]
 kzalloc_noprof include/linux/slab.h:775 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283
 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_fstat fs/stat.c:198 [inline]
 vfs_fstatat+0xd6/0x190 fs/stat.c:300
 __do_sys_newfstatat fs/stat.c:468 [inline]
 __se_sys_newfstatat fs/stat.c:462 [inline]
 __x64_sys_newfstatat+0x125/0x1b0 fs/stat.c:462
 do_syscall_64+0xfb/0x240
page last free pid 4548 tgid 4548 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1110 [inline]
 free_unref_page+0xd3c/0xec0 mm/page_alloc.c:2617
 __slab_free+0x31b/0x3d0 mm/slub.c:4274
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3867 [inline]
 slab_alloc_node mm/slub.c:3927 [inline]
 __do_kmalloc_node mm/slub.c:4047 [inline]
 __kmalloc_noprof+0x1a9/0x410 mm/slub.c:4061
 kmalloc_noprof include/linux/slab.h:664 [inline]
 tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path2_perm+0x3eb/0xbb0 security/tomoyo/file.c:923
 tomoyo_path_rename+0x198/0x1e0 security/tomoyo/tomoyo.c:300
 security_path_rename+0x179/0x220 security/security.c:1918
 do_renameat2+0x94a/0x13f0 fs/namei.c:5027
 __do_sys_rename fs/namei.c:5087 [inline]
 __se_sys_rename fs/namei.c:5085 [inline]
 __x64_sys_rename+0x86/0xa0 fs/namei.c:5085
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Memory state around the buggy address:
 ffff8880203f2d80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880203f2e00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff8880203f2e80: 00 00 00 00 04 fc fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff8880203f2f00: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
 ffff8880203f2f80: fa fb fb fb fb fb fb fb fc fc fc fc 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@...glegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

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

Powered by blists - more mailing lists