linux-ext4 - [PATCH 18/16] fuse2fs: make norecovery behavior consistent with the kernel

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251020202651.GN6170@frogsfrogsfrogs>
Date: Mon, 20 Oct 2025 13:26:51 -0700
From: "Darrick J. Wong" <djwong@...nel.org>
To: tytso@....edu
Cc: linux-ext4@...r.kernel.org
Subject: [PATCH 18/16] fuse2fs: make norecovery behavior consistent with the
 kernel

From: Darrick J. Wong <djwong@...nel.org>

Amazingly, norecovery/noload on the kernel ext4 driver allows a
read-write mount even for journalled filesystems.  The one case where
mounting fails is if there's a journal and it's dirty AND you didn't
specify norecovery.  Make the fuse2fs option behave the same as the
kernel.

Also, ext2fs_run_ext3_journal doesn't explicitly check EXT2_FILE_RW
state, which means fuse2fs must do that.

Found via ext4/271.

Cc: <linux-ext4@...r.kernel.org> # v1.43
Fixes: 81cbf1ef4f5dab ("misc: add fuse2fs, a FUSE server for e2fsprogs")
Signed-off-by: "Darrick J. Wong" <djwong@...nel.org>
---
 misc/fuse2fs.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c
index 931e60f61e85b6..9922747728a438 100644
--- a/misc/fuse2fs.c
+++ b/misc/fuse2fs.c
@@ -4818,6 +4818,11 @@ int main(int argc, char *argv[])
  _("Mounting read-only without recovering journal."));
 			fctx.ro = 1;
 			global_fs->flags &= ~EXT2_FLAG_RW;
+		} else if (!(global_fs->flags & EXT2_FLAG_RW)) {
+			err_printf(&fctx, "%s\n",
+ _("Cannot replay journal on read-only device."));
+			ret = 32;
+			goto out;
 		} else {
 			log_printf(&fctx, "%s\n", _("Recovering journal."));
 			err = ext2fs_run_ext3_journal(&global_fs);