Linux-mtd Archive on lore.kernel.org
 help / color / Atom feed
From: syzbot <syzbot+0ce97ea45b008ba3b8bd@syzkaller.appspotmail.com>
To: linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org,
	 miquel.raynal@bootlin.com, richard@nod.at,
	syzkaller-bugs@googlegroups.com,  vigneshr@ti.com
Subject: KASAN: use-after-free Read in uif_close
Date: Fri, 22 May 2020 15:34:16 -0700
Message-ID: <000000000000ba47b705a6443a0d@google.com> (raw)

Hello,

syzbot found the following crash on:

HEAD commit:    c11d28ab Add linux-next specific files for 20200522
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1089b706100000
kernel config:  https://syzkaller.appspot.com/x/.config?x=3f6dbdea4159fb66
dashboard link: https://syzkaller.appspot.com/bug?extid=0ce97ea45b008ba3b8bd
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15044ee2100000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+0ce97ea45b008ba3b8bd@syzkaller.appspotmail.com

ubi0: attaching mtd0
ubi0: scanning is finished
ubi0: empty MTD device detected
ubi0 error: ubi_attach_mtd_dev: cannot spawn "ubi_bgt0d", error -4
==================================================================
BUG: KASAN: use-after-free in uif_close+0x15e/0x190 drivers/mtd/ubi/build.c:502
Read of size 4 at addr ffff888097fe49e8 by task syz-executor.0/7033

CPU: 0 PID: 7033 Comm: syz-executor.0 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0
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+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 uif_close+0x15e/0x190 drivers/mtd/ubi/build.c:502
 ubi_attach_mtd_dev+0x157e/0x27c0 drivers/mtd/ubi/build.c:1036
 ctrl_cdev_ioctl+0x229/0x2b0 drivers/mtd/ubi/cdev.c:1043
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca29
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fd94dd97c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004e1080 RCX: 000000000045ca29
RDX: 0000000000742508 RSI: 0000000040186f40 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000209 R14: 00000000004c44c1 R15: 00007fd94dd986d4

Allocated by task 7033:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc mm/kasan/common.c:494 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 ubi_attach_mtd_dev+0x2e7/0x27c0 drivers/mtd/ubi/build.c:901
 ctrl_cdev_ioctl+0x229/0x2b0 drivers/mtd/ubi/cdev.c:1043
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 7033:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 kasan_set_free_info mm/kasan/common.c:316 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 device_release+0x71/0x200 drivers/base/core.c:1541
 kobject_cleanup lib/kobject.c:701 [inline]
 kobject_release lib/kobject.c:732 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1c8/0x2f0 lib/kobject.c:749
 cdev_device_del+0x69/0x80 fs/char_dev.c:575
 uif_close+0xea/0x190 drivers/mtd/ubi/build.c:501
 ubi_attach_mtd_dev+0x157e/0x27c0 drivers/mtd/ubi/build.c:1036
 ctrl_cdev_ioctl+0x229/0x2b0 drivers/mtd/ubi/cdev.c:1043
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

The buggy address belongs to the object at ffff888097fe4000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 2536 bytes inside of
 8192-byte region [ffff888097fe4000, ffff888097fe6000)
The buggy address belongs to the page:
page:ffffea00025ff900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea00025ff900 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea000267f108 ffffea0002460708 ffff8880aa0021c0
raw: 0000000000000000 ffff888097fe4000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888097fe4880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888097fe4900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888097fe4980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff888097fe4a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888097fe4a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

             reply index

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-22 22:34 syzbot [this message]
2020-05-23 14:37 ` syzbot
2020-05-24  6:03 ` syzbot
2020-05-24  8:09   ` Richard Weinberger
2020-05-24 11:14     ` Arnd Bergmann

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=000000000000ba47b705a6443a0d@google.com \
    --to=syzbot+0ce97ea45b008ba3b8bd@syzkaller.appspotmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mtd@lists.infradead.org \
    --cc=miquel.raynal@bootlin.com \
    --cc=richard@nod.at \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=vigneshr@ti.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

Linux-mtd Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-mtd/0 linux-mtd/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-mtd linux-mtd/ https://lore.kernel.org/linux-mtd \
		linux-mtd@lists.infradead.org
	public-inbox-index linux-mtd

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-mtd


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git