From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C47B25EF9C; Tue, 11 Mar 2025 15:06:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741705573; cv=none; b=vBY6o+acnZHEopxOu+1+qvdrmm59018xLguepH2LtVpsCiuH7ATFFfnv4ElJJQrGNTiBNfFAt+u7Emd/5TXumaxG22RRwkY1+ssXWSgD+MkBAknHfN3JKBkRinwfCr89XHM5xjSMoLoZ23DTf7gFBpA0kRIkojpreF7jMo30FnQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741705573; c=relaxed/simple; bh=ITeZpcRnXKBv+e1yOy/V48DD+O/KmV7IWyUUmRoVkbI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WDHLPZVVWUr1J1j0uiYQbo5r1dN2vdwLTsBt88vzs0fWL2JcLLN73Z4pE5XouzALjR5qIJhk/XS8k/lg1wr+NKr6YIbDBCDyvtk7tHbJSU3zUNlcp/jOXQGGuryCnpGfNcZ9RctFqs8rHHnCVdEFxb8oT2225yJIFeeIqHPJe00= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=g0LH6zlI; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="g0LH6zlI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D08FAC4CEED; Tue, 11 Mar 2025 15:06:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741705573; bh=ITeZpcRnXKBv+e1yOy/V48DD+O/KmV7IWyUUmRoVkbI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g0LH6zlIwLklMQ7MGOWOBHGjrnzoBubvYU6GH7Lex3XXdPn+KiunBUyBr6f2eb1/v 8BAjClkiuQP6w7Ja8IT7xa1TztbPO5Jqj6uYF5GGlptrD3L4bz5KgKbYGzAAr1sBZB +ln3KwQfqwGsjhFyIrV4Kn9xQS5fI63VSuDB5ZqY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, pangliyuan , Zhihao Cheng , Richard Weinberger , Sasha Levin Subject: [PATCH 5.4 062/328] ubifs: skip dumping tnc tree when zroot is null Date: Tue, 11 Mar 2025 15:57:12 +0100 Message-ID: <20250311145717.358450672@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250311145714.865727435@linuxfoundation.org> References: <20250311145714.865727435@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: pangliyuan [ Upstream commit bdb0ca39e0acccf6771db49c3f94ed787d05f2d7 ] Clearing slab cache will free all znode in memory and make c->zroot.znode = NULL, then dumping tnc tree will access c->zroot.znode which cause null pointer dereference. Link: https://bugzilla.kernel.org/show_bug.cgi?id=219624#c0 Fixes: 1e51764a3c2a ("UBIFS: add new flash file system") Signed-off-by: pangliyuan Reviewed-by: Zhihao Cheng Signed-off-by: Richard Weinberger Signed-off-by: Sasha Levin --- fs/ubifs/debug.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c index 992b74f9c9414..b5efbaf7eac2b 100644 --- a/fs/ubifs/debug.c +++ b/fs/ubifs/debug.c @@ -925,16 +925,20 @@ void ubifs_dump_tnc(struct ubifs_info *c) pr_err("\n"); pr_err("(pid %d) start dumping TNC tree\n", current->pid); - znode = ubifs_tnc_levelorder_next(c, c->zroot.znode, NULL); - level = znode->level; - pr_err("== Level %d ==\n", level); - while (znode) { - if (level != znode->level) { - level = znode->level; - pr_err("== Level %d ==\n", level); + if (c->zroot.znode) { + znode = ubifs_tnc_levelorder_next(c, c->zroot.znode, NULL); + level = znode->level; + pr_err("== Level %d ==\n", level); + while (znode) { + if (level != znode->level) { + level = znode->level; + pr_err("== Level %d ==\n", level); + } + ubifs_dump_znode(c, znode); + znode = ubifs_tnc_levelorder_next(c, c->zroot.znode, znode); } - ubifs_dump_znode(c, znode); - znode = ubifs_tnc_levelorder_next(c, c->zroot.znode, znode); + } else { + pr_err("empty TNC tree in memory\n"); } pr_err("(pid %d) finish dumping TNC tree\n", current->pid); } -- 2.39.5