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 E0A161ED38 for ; Tue, 25 Jul 2023 11:08:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 639B2C433C8; Tue, 25 Jul 2023 11:08:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690283327; bh=b5DAxg33cj2tHPTxN31GKwPM82ZUFVAQXamkAOWTxKc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zA3iXncDjKzMMglIocWdk1dCyTbc+lmPf3Fj4X5t6+K35vN5b3xcEPrzFBVdv/TGB sozD1ae9f/cCLDTzU2grQtSbQySNj6Pk20JNCXZT1/l756B0BI79GFyLY5BcBPEyz6 km+dTRTPapiVbZQ3eN6+6sQ1s1bohPcDHsT+l+eI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Immad Mir , Dave Kleikamp , Sasha Levin Subject: [PATCH 5.15 37/78] [PATCH AUTOSEL 4.14 9/9] FS: JFS: Check for read-only mounted filesystem in txBegin Date: Tue, 25 Jul 2023 12:46:28 +0200 Message-ID: <20230725104452.740868338@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104451.275227789@linuxfoundation.org> References: <20230725104451.275227789@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 95e2b352c03b0a86c5717ba1d24ea20969abcacc ] This patch adds a check for read-only mounted filesystem in txBegin before starting a transaction potentially saving from NULL pointer deref. Signed-off-by: Immad Mir Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin --- fs/jfs/jfs_txnmgr.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/fs/jfs/jfs_txnmgr.c +++ b/fs/jfs/jfs_txnmgr.c @@ -354,6 +354,11 @@ tid_t txBegin(struct super_block *sb, in jfs_info("txBegin: flag = 0x%x", flag); log = JFS_SBI(sb)->log; + if (!log) { + jfs_error(sb, "read-only filesystem\n"); + return 0; + } + TXN_LOCK(); INCREMENT(TxStat.txBegin);