From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x226Fzb4L+CO820Xug+ubajs4mvhEH9WmDb9BG6hBvcoKJ290FtRYsB1DgJQK2wiflXuNIGEF ARC-Seal: i=1; a=rsa-sha256; t=1519218705; cv=none; d=google.com; s=arc-20160816; b=oVw2Z9il9X7si5PwZhXz2PdtmNqFKsxQFhnBM9pDBLp75C8lrU2sN9OYu9bB3mIxHr yo1OYQO+zt2IKr3tX9tSREP0Fe5PQbdgIPQQYvpCHetBYaqYV91u+yDkHLR1nh9x5Ens rbJBJnBSXdv9SL4SALhzqUsjnbfhqUN2ePJDqLUxkQVtA67vIO0w1aJpiDyUEDyXbhUE nl/pKmwtDyA4kIURGqbE39lJZrDu83gsAWwpdwYCl6oJ7MgTYWyPE8j1+m4jXVI5Ms/5 ruSPg3NdMeL4SvszOVu46n2JvfaH7Rj7x/pxnDUp+zdgQjPlD42nZ88vgFrThMY29zRY A0Yw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=yaDIxE3oYVTOJIfJOXf2bs2/2DYqMxO84IxCRS17yhU=; b=m8MF+htGRrjEwO1yUzde+gLGEYVdBdonkZcysSEyWQfoX8oyyj/ikcoOlPkF3jxedd WYIIbaydm1WwRRa7pE783iiRg/Yb+8CddOpLCafkl+ADlBRYn8+4OEF4mPvwtD7p54Xh jOmKpLlLCSZQj6erFO4ZRHSjWjryAXQDqhRdEM4J9x2VRzxdRkXZQteWitszeQKnAo2B ExeHFg/+6N/lg+7nJCm3w0MlTTmPCwMCnr5gUuPBlzewIFAQ2dwln5M3abYlv9Mif5fF CXtpdLH8aMv6lHVjWEbkzv/lZpMtb8s9jiWW4DrhYeR3jWnCcWBYF6JKguoFOesxTtI5 WM4w== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Potapenko , Eric Biggers Subject: [PATCH 4.15 100/163] mbcache: initialize entry->e_referenced in mb_cache_entry_create() Date: Wed, 21 Feb 2018 13:48:49 +0100 Message-Id: <20180221124535.820576980@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180221124529.931834518@linuxfoundation.org> References: <20180221124529.931834518@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1593015301228685105?= X-GMAIL-MSGID: =?utf-8?q?1593016273756488531?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexander Potapenko commit 3876bbe27d04b848750d5310a37d6b76b593f648 upstream. KMSAN reported use of uninitialized |entry->e_referenced| in a condition in mb_cache_shrink(): ================================================================== BUG: KMSAN: use of uninitialized memory in mb_cache_shrink+0x3b4/0xc50 fs/mbcache.c:287 CPU: 2 PID: 816 Comm: kswapd1 Not tainted 4.11.0-rc5+ #2877 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x172/0x1c0 lib/dump_stack.c:52 kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:927 __msan_warning_32+0x61/0xb0 mm/kmsan/kmsan_instr.c:469 mb_cache_shrink+0x3b4/0xc50 fs/mbcache.c:287 mb_cache_scan+0x67/0x80 fs/mbcache.c:321 do_shrink_slab mm/vmscan.c:397 [inline] shrink_slab+0xc3d/0x12d0 mm/vmscan.c:500 shrink_node+0x208f/0x2fd0 mm/vmscan.c:2603 kswapd_shrink_node mm/vmscan.c:3172 [inline] balance_pgdat mm/vmscan.c:3289 [inline] kswapd+0x160f/0x2850 mm/vmscan.c:3478 kthread+0x46c/0x5f0 kernel/kthread.c:230 ret_from_fork+0x29/0x40 arch/x86/entry/entry_64.S:430 chained origin: save_stack_trace+0x37/0x40 arch/x86/kernel/stacktrace.c:59 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:302 [inline] kmsan_save_stack mm/kmsan/kmsan.c:317 [inline] kmsan_internal_chain_origin+0x12a/0x1f0 mm/kmsan/kmsan.c:547 __msan_store_shadow_origin_1+0xac/0x110 mm/kmsan/kmsan_instr.c:257 mb_cache_entry_create+0x3b3/0xc60 fs/mbcache.c:95 ext4_xattr_cache_insert fs/ext4/xattr.c:1647 [inline] ext4_xattr_block_set+0x4c82/0x5530 fs/ext4/xattr.c:1022 ext4_xattr_set_handle+0x1332/0x20a0 fs/ext4/xattr.c:1252 ext4_xattr_set+0x4d2/0x680 fs/ext4/xattr.c:1306 ext4_xattr_trusted_set+0x8d/0xa0 fs/ext4/xattr_trusted.c:36 __vfs_setxattr+0x703/0x790 fs/xattr.c:149 __vfs_setxattr_noperm+0x27a/0x6f0 fs/xattr.c:180 vfs_setxattr fs/xattr.c:223 [inline] setxattr+0x6ae/0x790 fs/xattr.c:449 path_setxattr+0x1eb/0x380 fs/xattr.c:468 SYSC_lsetxattr+0x8d/0xb0 fs/xattr.c:490 SyS_lsetxattr+0x77/0xa0 fs/xattr.c:486 entry_SYSCALL_64_fastpath+0x13/0x94 origin: save_stack_trace+0x37/0x40 arch/x86/kernel/stacktrace.c:59 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:302 [inline] kmsan_internal_poison_shadow+0xb1/0x1a0 mm/kmsan/kmsan.c:198 kmsan_kmalloc+0x7f/0xe0 mm/kmsan/kmsan.c:337 kmem_cache_alloc+0x1c2/0x1e0 mm/slub.c:2766 mb_cache_entry_create+0x283/0xc60 fs/mbcache.c:86 ext4_xattr_cache_insert fs/ext4/xattr.c:1647 [inline] ext4_xattr_block_set+0x4c82/0x5530 fs/ext4/xattr.c:1022 ext4_xattr_set_handle+0x1332/0x20a0 fs/ext4/xattr.c:1252 ext4_xattr_set+0x4d2/0x680 fs/ext4/xattr.c:1306 ext4_xattr_trusted_set+0x8d/0xa0 fs/ext4/xattr_trusted.c:36 __vfs_setxattr+0x703/0x790 fs/xattr.c:149 __vfs_setxattr_noperm+0x27a/0x6f0 fs/xattr.c:180 vfs_setxattr fs/xattr.c:223 [inline] setxattr+0x6ae/0x790 fs/xattr.c:449 path_setxattr+0x1eb/0x380 fs/xattr.c:468 SYSC_lsetxattr+0x8d/0xb0 fs/xattr.c:490 SyS_lsetxattr+0x77/0xa0 fs/xattr.c:486 entry_SYSCALL_64_fastpath+0x13/0x94 ================================================================== Signed-off-by: Alexander Potapenko Signed-off-by: Eric Biggers Cc: stable@vger.kernel.org # v4.6 Signed-off-by: Greg Kroah-Hartman --- fs/mbcache.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/mbcache.c +++ b/fs/mbcache.c @@ -94,6 +94,7 @@ int mb_cache_entry_create(struct mb_cach entry->e_key = key; entry->e_value = value; entry->e_reusable = reusable; + entry->e_referenced = 0; head = mb_cache_entry_head(cache, key); hlist_bl_lock(head); hlist_bl_for_each_entry(dup, dup_node, head, e_hash_list) {