From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f71.google.com (mail-io1-f71.google.com [209.85.166.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 048EB126BF6 for ; Sun, 22 Sep 2024 11:43:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.71 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727005385; cv=none; b=YAUPepH4QBdGR+47XKbBcQ/OyYwm7KDlHzukWCkC4JPh73w9EE0hbpt8C+0DWIvro6giErH/V8oqKXV05Pud4VG5SuVW6U5IKCbwRhT1Z8BeXvifGzoM9V5utXPzAaVH+d4v4eo/yUA5yGaMXn9IXff3PjogKFDPsiKO3QtYmwo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727005385; c=relaxed/simple; bh=EPf0nnywD0niFpTQOXAPIemPZxBmfJ1AMrM99RvGy4c=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=t3RmgZjMVAOVBr4oy/mzVUHGXgjspYTAjA9E8ubEbI1W8ceySf8VYQaNUdiadOrfwp5htbTQArE0qfobXVSfIiLklGs4fISIp2Stp2zvrWko/f4FAm1XO03EXa11HWlY4MFu0BxgzMC560JmBSQ7am1SQri3rmnQHdtBiyexEgo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.71 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f71.google.com with SMTP id ca18e2360f4ac-82cd9c20b2bso479883339f.1 for ; Sun, 22 Sep 2024 04:43:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1727005383; x=1727610183; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=aLi2ud1YrNOTbnPgH971uSVNjS9RgWm0J+mPsuQ1+ec=; b=oSrI/Z2iej1A1RtDuh+p2GcCbTUdNJS5a4/66w9ufudeq23mIsJGLbzqY4W+1lI4XU NA9ruR3jTkgWNtWuMglU2VipepQtRQR4fWsTnfyr010kc1v1LaxoX2VkwCzjAyIjgIhV VPJkPVdtJDBjHcua1UHtdr8rEoxHfX9yrZwU3mt6F7eLdV5TJHXPyIeHIAuq8dbCkDr8 b0TalkqYgZq1YDXO9g24AVSTF/bS/IMi4HkHxqHJ2CUm86Of/jrc3oQ1FmbsqKaa8swO 8ZmjkM6ZmcxbE0OSK7nDGqavqaEOE5fK9U6aHrpALsbv767D9Jl7J0dzc/SoBuMYYd8p L9ew== X-Forwarded-Encrypted: i=1; AJvYcCVsHBL9QJk7repDQP5IlcHUd373skFd0yhcg19KE7W4nwzsXoH240BD+ylzbhjwgyn078D7H4fFcZk2Suc=@vger.kernel.org X-Gm-Message-State: AOJu0YwzXpMkCN750zrwUgBjK2CeMPnPTpqRS8hoE5V7+dcHXUW7D1JF dL5z1qnongH8xAw8HTvnPSf2CGDPIwJ8hogpA9nlhNA5Hwb90PE/wbMMoupGBCA+VoFVB3Tq2s0 Mnd4+SQfhualFxPf1ugUd6A1fAHIESbwZQxfFiI6uT8LHXtZ8d5AOyow= X-Google-Smtp-Source: AGHT+IFM9ZEuGEIuZuX40SVqB5D8L7YbOd0D9A7KP1xYu9BCfF+DFyvYhUywTy5gw8yKDXxur34NDfiws80782ihXI+Y6OABNnb2 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1908:b0:3a0:911d:c277 with SMTP id e9e14a558f8ab-3a0c8c6a282mr78314455ab.5.1727005383062; Sun, 22 Sep 2024 04:43:03 -0700 (PDT) Date: Sun, 22 Sep 2024 04:43:03 -0700 In-Reply-To: X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <66f002c7.050a0220.1b7b75.0002.GAE@google.com> Subject: Re: [syzbot] [keyrings?] [lsm?] [ext4?] possible deadlock in keyring_clear (2) From: syzbot To: dhowells@redhat.com, eadavis@qq.com, jarkko@kernel.org, jmorris@namei.org, keyrings@vger.kernel.org, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, paul@paul-moore.com, serge@hallyn.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: possible deadlock in keyring_clear ====================================================== WARNING: possible circular locking dependency detected 6.11.0-syzkaller-08481-g88264981f208-dirty #0 Not tainted ------------------------------------------------------ kswapd0/79 is trying to acquire lock: ffff888000b01258 (&type->lock_class){+.+.}-{3:3}, at: keyring_clear+0xb2/0x350 security/keys/keyring.c:1655 but task is already holding lock: ffffffff8ea36740 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6844 [inline] ffffffff8ea36740 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3700 mm/vmscan.c:7226 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __fs_reclaim_acquire mm/page_alloc.c:3834 [inline] fs_reclaim_acquire+0x88/0x140 mm/page_alloc.c:3848 might_alloc include/linux/sched/mm.h:327 [inline] slab_pre_alloc_hook mm/slub.c:4037 [inline] slab_alloc_node mm/slub.c:4115 [inline] __kmalloc_cache_noprof+0x3d/0x2c0 mm/slub.c:4291 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] assoc_array_insert_in_empty_tree lib/assoc_array.c:457 [inline] assoc_array_insert+0x52c/0x33e0 lib/assoc_array.c:991 __key_link_begin+0xe5/0x1f0 security/keys/keyring.c:1314 __key_create_or_update+0x570/0xc70 security/keys/key.c:874 key_create_or_update+0x42/0x60 security/keys/key.c:1018 x509_load_certificate_list+0x149/0x270 crypto/asymmetric_keys/x509_loader.c:31 do_one_initcall+0x248/0x880 init/main.c:1269 do_initcall_level+0x157/0x210 init/main.c:1331 do_initcalls+0x3f/0x80 init/main.c:1347 kernel_init_freeable+0x435/0x5d0 init/main.c:1580 kernel_init+0x1d/0x2b0 init/main.c:1469 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (&type->lock_class){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3158 [inline] check_prevs_add kernel/locking/lockdep.c:3277 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_write+0x99/0x220 kernel/locking/rwsem.c:1579 keyring_clear+0xb2/0x350 security/keys/keyring.c:1655 fscrypt_put_master_key+0xc8/0x190 fs/crypto/keyring.c:79 put_crypt_info+0x275/0x320 fs/crypto/keysetup.c:548 fscrypt_put_encryption_info+0x40/0x60 fs/crypto/keysetup.c:753 ext4_clear_inode+0x15b/0x1c0 fs/ext4/super.c:1525 ext4_evict_inode+0xabc/0xf50 fs/ext4/inode.c:323 evict+0x4e8/0x9b0 fs/inode.c:731 __dentry_kill+0x20d/0x630 fs/dcache.c:615 shrink_kill+0xa9/0x2c0 fs/dcache.c:1060 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1087 prune_dcache_sb+0x10f/0x180 fs/dcache.c:1168 super_cache_scan+0x34f/0x4b0 fs/super.c:221 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0x878/0x14d0 mm/shrinker.c:626 shrink_one+0x43b/0x850 mm/vmscan.c:4818 shrink_many mm/vmscan.c:4879 [inline] lru_gen_shrink_node mm/vmscan.c:4957 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5937 kswapd_shrink_node mm/vmscan.c:6765 [inline] balance_pgdat mm/vmscan.c:6957 [inline] kswapd+0x1ca3/0x3700 mm/vmscan.c:7226 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&type->lock_class); lock(fs_reclaim); lock(&type->lock_class); *** DEADLOCK *** 2 locks held by kswapd0/79: #0: ffffffff8ea36740 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6844 [inline] #0: ffffffff8ea36740 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3700 mm/vmscan.c:7226 #1: ffff888035f440e0 (&type->s_umount_key#32){++++}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff888035f440e0 (&type->s_umount_key#32){++++}-{3:3}, at: super_cache_scan+0x94/0x4b0 fs/super.c:196 stack backtrace: CPU: 0 UID: 0 PID: 79 Comm: kswapd0 Not tainted 6.11.0-syzkaller-08481-g88264981f208-dirty #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2203 check_prev_add kernel/locking/lockdep.c:3158 [inline] check_prevs_add kernel/locking/lockdep.c:3277 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_write+0x99/0x220 kernel/locking/rwsem.c:1579 keyring_clear+0xb2/0x350 security/keys/keyring.c:1655 fscrypt_put_master_key+0xc8/0x190 fs/crypto/keyring.c:79 put_crypt_info+0x275/0x320 fs/crypto/keysetup.c:548 fscrypt_put_encryption_info+0x40/0x60 fs/crypto/keysetup.c:753 ext4_clear_inode+0x15b/0x1c0 fs/ext4/super.c:1525 ext4_evict_inode+0xabc/0xf50 fs/ext4/inode.c:323 evict+0x4e8/0x9b0 fs/inode.c:731 __dentry_kill+0x20d/0x630 fs/dcache.c:615 shrink_kill+0xa9/0x2c0 fs/dcache.c:1060 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1087 prune_dcache_sb+0x10f/0x180 fs/dcache.c:1168 super_cache_scan+0x34f/0x4b0 fs/super.c:221 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0x878/0x14d0 mm/shrinker.c:626 shrink_one+0x43b/0x850 mm/vmscan.c:4818 shrink_many mm/vmscan.c:4879 [inline] lru_gen_shrink_node mm/vmscan.c:4957 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5937 kswapd_shrink_node mm/vmscan.c:6765 [inline] balance_pgdat mm/vmscan.c:6957 [inline] kswapd+0x1ca3/0x3700 mm/vmscan.c:7226 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Tested on: commit: 88264981 Merge tag 'sched_ext-for-6.12' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14ee4e07980000 kernel config: https://syzkaller.appspot.com/x/.config?x=e851828834875d6f dashboard link: https://syzkaller.appspot.com/bug?extid=1b2d1134e0b675176a15 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 patch: https://syzkaller.appspot.com/x/patch.diff?x=174eec27980000