From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 28467C4332F for ; Fri, 14 Jan 2022 10:18:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=6f1GiXdbNyQO4zrYVyxlwPBuxnFb5BUBryFuzohZKGk=; b=dqiYgah7syDaeD wviWRrjOVtDob9nxlTC5bRzU/UzMzzqIlReUgz5zU2cTazL9GWhfOLa6YYjkgQUTc+Ep/z6dLC85C N/bWP0uBmQ3ehSngkgynoSxlyauvxZfVHsPe04EQ2s1BdBjKDevyYysoZs92l2W3AYCz5q02GTA6o LjdHLpMMwSTFjaZgBfSkNXkqG7cGsiL790FZg7uS9Skc2jsMevdK+j5GdbdM7DVNTxOE7f7HQePEx zMchC46DOwdOQDlG9IEqw4r1/snIfStUbhKLrRDxylVnpCx5vkrgyyGN18iXNF1yhyty+FMsO3SDN L7lbQwQqvAxcTS8K372w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n8Jev-008fYi-3r; Fri, 14 Jan 2022 10:18:13 +0000 Received: from szxga02-in.huawei.com ([45.249.212.188]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1n8Jee-008fRh-VD for linux-mtd@lists.infradead.org; Fri, 14 Jan 2022 10:17:58 +0000 Received: from dggpeml500020.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4JZxzb1tNWz9sFc; Fri, 14 Jan 2022 18:16:43 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500020.china.huawei.com (7.185.36.88) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Fri, 14 Jan 2022 18:17:52 +0800 From: Baokun Li To: , , , CC: , , Subject: [PATCH -next v3 2/2] jffs2: fix memory leak in jffs2_scan_medium Date: Fri, 14 Jan 2022 18:28:54 +0800 Message-ID: <20220114102854.3399585-3-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220114102854.3399585-1-libaokun1@huawei.com> References: <20220114102854.3399585-1-libaokun1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpeml500020.china.huawei.com (7.185.36.88) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220114_021757_390333_FCC12479 X-CRM114-Status: UNSURE ( 9.73 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org If an error is returned in jffs2_scan_eraseblock() and some memory has been added to the jffs2_summary *s, we can observe the following kmemleak report: -------------------------------------------- unreferenced object 0xffff88812b889c40 (size 64): comm "mount", pid 692, jiffies 4294838325 (age 34.288s) hex dump (first 32 bytes): 40 48 b5 14 81 88 ff ff 01 e0 31 00 00 00 50 00 @H........1...P. 00 00 01 00 00 00 01 00 00 00 02 00 00 00 09 08 ................ backtrace: [] __kmalloc+0x613/0x910 [] jffs2_sum_add_dirent_mem+0x5c/0xa0 [] jffs2_scan_medium.cold+0x36e5/0x4794 [] jffs2_do_mount_fs.cold+0xa7/0x2267 [] jffs2_do_fill_super+0x383/0xc30 [] jffs2_fill_super+0x2ea/0x4c0 [] mtd_get_sb+0x254/0x400 [] mtd_get_sb_by_nr+0x4f/0xd0 [] get_tree_mtd+0x498/0x840 [] jffs2_get_tree+0x25/0x30 [] vfs_get_tree+0x8d/0x2e0 [] path_mount+0x50f/0x1e50 [] do_mount+0x107/0x130 [] __se_sys_mount+0x1c5/0x2f0 [] __x64_sys_mount+0xc7/0x160 [] do_syscall_64+0x45/0x70 unreferenced object 0xffff888114b54840 (size 32): comm "mount", pid 692, jiffies 4294838325 (age 34.288s) hex dump (first 32 bytes): c0 75 b5 14 81 88 ff ff 02 e0 02 00 00 00 02 00 .u.............. 00 00 84 00 00 00 44 00 00 00 6b 6b 6b 6b 6b a5 ......D...kkkkk. backtrace: [] kmem_cache_alloc_trace+0x584/0x880 [] jffs2_sum_add_inode_mem+0x54/0x90 [] jffs2_scan_medium.cold+0x4481/0x4794 [...] unreferenced object 0xffff888114b57280 (size 32): comm "mount", pid 692, jiffies 4294838393 (age 34.357s) hex dump (first 32 bytes): 10 d5 6c 11 81 88 ff ff 08 e0 05 00 00 00 01 00 ..l............. 00 00 38 02 00 00 28 00 00 00 6b 6b 6b 6b 6b a5 ..8...(...kkkkk. backtrace: [] kmem_cache_alloc_trace+0x584/0x880 [] jffs2_sum_add_xattr_mem+0x54/0x90 [] jffs2_scan_medium.cold+0x298c/0x4794 [...] unreferenced object 0xffff8881116cd510 (size 16): comm "mount", pid 692, jiffies 4294838395 (age 34.355s) hex dump (first 16 bytes): 00 00 00 00 00 00 00 00 09 e0 60 02 00 00 6b a5 ..........`...k. backtrace: [] kmem_cache_alloc_trace+0x584/0x880 [] jffs2_sum_add_xref_mem+0x54/0x90 [] jffs2_scan_medium.cold+0x3a20/0x4794 [...] -------------------------------------------- Therefore, we should call jffs2_sum_reset_collected(s) on exit to release the memory added in s. In addition, a new tag "out_buf" is added to prevent the NULL pointer reference caused by s being NULL. (thanks to Zhang Yi for this analysis) Fixes: e631ddba5887 ("[JFFS2] Add erase block summary support (mount time improvement)") Cc: stable@vger.kernel.org Co-developed-with: Zhihao Cheng Signed-off-by: Baokun Li --- fs/jffs2/scan.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c index b676056826be..29671e33a171 100644 --- a/fs/jffs2/scan.c +++ b/fs/jffs2/scan.c @@ -136,7 +136,7 @@ int jffs2_scan_medium(struct jffs2_sb_info *c) if (!s) { JFFS2_WARNING("Can't allocate memory for summary\n"); ret = -ENOMEM; - goto out; + goto out_buf; } } @@ -275,13 +275,15 @@ int jffs2_scan_medium(struct jffs2_sb_info *c) } ret = 0; out: + jffs2_sum_reset_collected(s); + kfree(s); + out_buf: if (buf_size) kfree(flashbuf); #ifndef __ECOS else mtd_unpoint(c->mtd, 0, c->mtd->size); #endif - kfree(s); return ret; } -- 2.31.1 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/