From: syzbot <syzbot+2c49971e251e36216d1f@syzkaller.appspotmail.com>
To: akpm@linux-foundation.org, cai@lca.pw, crecklin@redhat.com,
keescook@chromium.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, syzkaller-bugs@googlegroups.com
Subject: WARNING: bad usercopy in fanotify_read
Date: Mon, 11 Mar 2019 13:42:06 -0700 [thread overview]
Message-ID: <00000000000016f7d40583d79bd9@google.com> (raw)
Hello,
syzbot found the following crash on:
HEAD commit: 12ad143e Merge branch 'perf-urgent-for-linus' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12776f57200000
kernel config: https://syzkaller.appspot.com/x/.config?x=e9d91b7192a5e96e
dashboard link: https://syzkaller.appspot.com/bug?extid=2c49971e251e36216d1f
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
userspace arch: amd64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1287516f200000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17ee410b200000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+2c49971e251e36216d1f@syzkaller.appspotmail.com
------------[ cut here ]------------
Bad or missing usercopy whitelist? Kernel memory exposure attempt detected
from SLAB object 'fanotify_event' (offset 40, size 8)!
WARNING: CPU: 1 PID: 7649 at mm/usercopy.c:78 usercopy_warn+0xeb/0x110
mm/usercopy.c:78
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 7649 Comm: syz-executor381 Not tainted 5.0.0+ #17
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
panic+0x2cb/0x65c kernel/panic.c:214
__warn.cold+0x20/0x45 kernel/panic.c:571
report_bug+0x263/0x2b0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:179 [inline]
fixup_bug arch/x86/kernel/traps.c:174 [inline]
do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:usercopy_warn+0xeb/0x110 mm/usercopy.c:78
Code: c8 e8 d9 88 c0 ff 4c 8b 45 c0 4d 89 e9 4c 89 e1 48 8b 55 c8 41 57 48
89 de 48 c7 c7 e0 dc 74 87 ff 75 d0 41 56 e8 03 4b 93 ff <0f> 0b 48 83 c4
18 e9 46 ff ff ff 49 c7 c5 e0 da 74 87 4d 89 ee 4d
RSP: 0018:ffff8880a417fb18 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffff8774dca0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815ad7b6 RDI: ffffed101482ff55
RBP: ffff8880a417fb70 R08: ffff888088d78580 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8859408d
R13: ffffffff8775d500 R14: ffffffff8774db20 R15: 0000000000000008
__check_heap_object+0x88/0xb3 mm/slab.c:4453
check_heap_object mm/usercopy.c:238 [inline]
__check_object_size mm/usercopy.c:284 [inline]
__check_object_size+0x342/0x42f mm/usercopy.c:254
check_object_size include/linux/thread_info.h:119 [inline]
check_copy_size include/linux/thread_info.h:150 [inline]
copy_to_user include/linux/uaccess.h:151 [inline]
copy_fid_to_user fs/notify/fanotify/fanotify_user.c:236 [inline]
copy_event_to_user fs/notify/fanotify/fanotify_user.c:294 [inline]
fanotify_read+0xde0/0x1430 fs/notify/fanotify/fanotify_user.c:362
__vfs_read+0x8d/0x110 fs/read_write.c:416
vfs_read+0x194/0x3e0 fs/read_write.c:452
ksys_read+0xea/0x1f0 fs/read_write.c:578
__do_sys_read fs/read_write.c:588 [inline]
__se_sys_read fs/read_write.c:586 [inline]
__x64_sys_read+0x73/0xb0 fs/read_write.c:586
do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4456b9
Code: e8 6c b6 02 00 48 83 c4 18 c3 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 0f 83 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb296f31db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 00000000004456b9
RDX: 000000000000006b RSI: 0000000020000000 RDI: 0000000000000004
RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac2c
R13: 00007ffd8eb3d16f R14: 00007fb296f329c0 R15: 20c49ba5e353f7cf
Kernel Offset: disabled
Rebooting in 86400 seconds..
---
This bug 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 bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with
syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches
next reply other threads:[~2019-03-11 20:42 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-11 20:42 syzbot [this message]
2019-03-13 6:26 ` WARNING: bad usercopy in fanotify_read Kees Cook
2019-03-13 6:42 ` Amir Goldstein
2019-03-13 14:35 ` Jan Kara
2019-03-13 15:35 ` Kees Cook
2019-03-13 15:47 ` Jan Kara
2019-03-18 18:27 ` Kees Cook
2019-03-19 8:32 ` Jan Kara
2019-03-16 14:49 ` syzbot
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=00000000000016f7d40583d79bd9@google.com \
--to=syzbot+2c49971e251e36216d1f@syzkaller.appspotmail.com \
--cc=akpm@linux-foundation.org \
--cc=cai@lca.pw \
--cc=crecklin@redhat.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=syzkaller-bugs@googlegroups.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.