From 5c094ca994824e038b6a97835ded4e5d1d808504 Mon Sep 17 00:00:00 2001 From: Immad Mir Date: Fri, 23 Jun 2023 19:17:08 +0530 Subject: FS: JFS: Check for read-only mounted filesystem in txBegin [ 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(+) (limited to 'fs/jfs') diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c index c8ce7f1bc594..6f6a5b9203d3 100644 --- a/fs/jfs/jfs_txnmgr.c +++ b/fs/jfs/jfs_txnmgr.c @@ -354,6 +354,11 @@ tid_t txBegin(struct super_block *sb, int flag) 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); -- cgit v1.2.3