From: Ye Bin <yebin10@xxxxxxxxxx>
commit ac2f7ca51b0929461ea49918f27c11b680f28995 upstream.
Before commit 014c9caa29d3 ("ext4: make ext4_abort() use
__ext4_error()"), the following series of commands would trigger a
panic:
1. mount /dev/sda -o ro,errors=panic test
2. mount /dev/sda -o remount,abort test
After commit 014c9caa29d3, remounting a file system using the test
mount option "abort" will no longer trigger a panic. This commit will
restore the behaviour immediately before commit 014c9caa29d3.
(However, note that the Linux kernel's behavior has not been
consistent; some previous kernel versions, including 5.4 and 4.19
similarly did not panic after using the mount option "abort".)
This also makes a change to long-standing behaviour; namely, the
following series commands will now cause a panic, when previously it
did not:
1. mount /dev/sda -o ro,errors=panic test
2. echo test > /sys/fs/ext4/sda/trigger_fs_error
However, this makes ext4's behaviour much more consistent, so this is
a good thing.
Cc: stable@xxxxxxxxxx
Fixes: 014c9caa29d3 ("ext4: make ext4_abort() use __ext4_error()")
Signed-off-by: Ye Bin <yebin10@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210401081903.3421208-1-yebin10@xxxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ext4/super.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -667,9 +667,6 @@ static void ext4_handle_error(struct sup
ext4_commit_super(sb);
}
- if (sb_rdonly(sb) || continue_fs)
- return;
-
/*
* We force ERRORS_RO behavior when system is rebooting. Otherwise we
* could panic during 'reboot -f' as the underlying device got already
@@ -679,6 +676,10 @@ static void ext4_handle_error(struct sup
panic("EXT4-fs (device %s): panic forced after error\n",
sb->s_id);
}
+
+ if (sb_rdonly(sb) || continue_fs)
+ return;
+
ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
/*
* Make sure updated value of ->s_mount_flags will be visible before
