mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: syzbot <syzbot+b214edc6e43f8da65554@syzkaller.appspotmail.com>
To: akpm@linux-foundation.org, ebiederm@xmission.com,
	legion@kernel.org, linux-kernel@vger.kernel.org,
	linux@rasmusvillemoes.dk, syzkaller-bugs@googlegroups.com,
	yangyingliang@huawei.com
Subject: [syzbot] memory leak in prepare_kernel_cred
Date: Mon, 20 Sep 2021 08:42:36 -0700	[thread overview]
Message-ID: <00000000000059730805cc6f2138@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    4357f03d6611 Merge tag 'pm-5.15-rc2' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16260b9b300000
kernel config:  https://syzkaller.appspot.com/x/.config?x=84e947373389eef5
dashboard link: https://syzkaller.appspot.com/bug?extid=b214edc6e43f8da65554
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17a7cb3b300000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=103f8f2d300000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b214edc6e43f8da65554@syzkaller.appspotmail.com

write to /proc/sys/kernel/hung_task_check_interval_secs failed: No such file or directory
write to /proc/sys/kernel/softlockup_all_cpu_backtrace failed: No such file or directory
BUG: memory leak
unreferenced object 0xffff8881046d5480 (size 176):
  comm "kworker/u4:0", pid 6631, jiffies 4294994696 (age 35.750s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81275931>] prepare_kernel_cred+0x21/0x2e0 kernel/cred.c:724
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

BUG: memory leak
unreferenced object 0xffff888102054040 (size 32):
  comm "kworker/u4:0", pid 6631, jiffies 4294994696 (age 35.750s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 b0 12 05 40 81 88 ff ff  ...........@....
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff8213e79f>] lsm_cred_alloc security/security.c:537 [inline]
    [<ffffffff8213e79f>] security_prepare_creds+0x9f/0xc0 security/security.c:1691
    [<ffffffff81275ab5>] prepare_kernel_cred+0x1a5/0x2e0 kernel/cred.c:760
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

BUG: memory leak
unreferenced object 0xffff8881046d50c0 (size 176):
  comm "kworker/u4:0", pid 6633, jiffies 4294994696 (age 35.750s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81275931>] prepare_kernel_cred+0x21/0x2e0 kernel/cred.c:724
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

BUG: memory leak
unreferenced object 0xffff88810493f6c0 (size 176):
  comm "kworker/u4:0", pid 6634, jiffies 4294994696 (age 35.750s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81275931>] prepare_kernel_cred+0x21/0x2e0 kernel/cred.c:724
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

BUG: memory leak
unreferenced object 0xffff888104cec5e0 (size 32):
  comm "kworker/u4:0", pid 6634, jiffies 4294994696 (age 35.750s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 b0 12 05 40 81 88 ff ff  ...........@....
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff8213e79f>] lsm_cred_alloc security/security.c:537 [inline]
    [<ffffffff8213e79f>] security_prepare_creds+0x9f/0xc0 security/security.c:1691
    [<ffffffff81275ab5>] prepare_kernel_cred+0x1a5/0x2e0 kernel/cred.c:760
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

BUG: memory leak
unreferenced object 0xffff88810382b780 (size 176):
  comm "kworker/u4:0", pid 6637, jiffies 4294994700 (age 35.710s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81275931>] prepare_kernel_cred+0x21/0x2e0 kernel/cred.c:724
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

BUG: memory leak
unreferenced object 0xffff888102054060 (size 32):
  comm "kworker/u4:0", pid 6637, jiffies 4294994700 (age 35.710s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 b0 12 05 40 81 88 ff ff  ...........@....
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff8213e79f>] lsm_cred_alloc security/security.c:537 [inline]
    [<ffffffff8213e79f>] security_prepare_creds+0x9f/0xc0 security/security.c:1691
    [<ffffffff81275ab5>] prepare_kernel_cred+0x1a5/0x2e0 kernel/cred.c:760
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

BUG: memory leak
unreferenced object 0xffff888104c0a780 (size 176):
  comm "kworker/u4:0", pid 6630, jiffies 4294994702 (age 35.690s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81275931>] prepare_kernel_cred+0x21/0x2e0 kernel/cred.c:724
    [<ffffffff8125fc6d>] call_usermodehelper_exec_async+0x5d/0x1c0 kernel/umh.c:91
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295



---
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.
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

                 reply	other threads:[~2021-09-20 15:42 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=00000000000059730805cc6f2138@google.com \
    --to=syzbot+b214edc6e43f8da65554@syzkaller.appspotmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=ebiederm@xmission.com \
    --cc=legion@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@rasmusvillemoes.dk \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=yangyingliang@huawei.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome