2008-03-17 23:54:29

by Andrew Morton

[permalink] [raw]
Subject: + jbd2-correctly-unescape-journal-data-blocks.patch added to -mm tree


The patch titled
jbd2: correctly unescape journal data blocks
has been added to the -mm tree. Its filename is
jbd2-correctly-unescape-journal-data-blocks.patch

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b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
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*** Remember to use Documentation/SubmitChecklist when testing your code ***

See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

------------------------------------------------------
Subject: jbd2: correctly unescape journal data blocks
From: "Duane Griffin" <[email protected]>

Fix a long-standing typo (predating git) that will cause data corruption if a
journal data block needs unescaping. At the moment the wrong buffer head's
data is being unescaped.

To test this case mount a filesystem with data=journal, start creating and
deleting a bunch of files containing only JBD2_MAGIC_NUMBER (0xc03b3998), then
pull the plug on the device. Without this patch the files will contain zeros
instead of the correct data after recovery.

Signed-off-by: Duane Griffin <[email protected]>
Acked-by: Jan Kara <[email protected]>
Cc: <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

fs/jbd2/recovery.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN fs/jbd2/recovery.c~jbd2-correctly-unescape-journal-data-blocks fs/jbd2/recovery.c
--- a/fs/jbd2/recovery.c~jbd2-correctly-unescape-journal-data-blocks
+++ a/fs/jbd2/recovery.c
@@ -535,7 +535,7 @@ static int do_one_pass(journal_t *journa
memcpy(nbh->b_data, obh->b_data,
journal->j_blocksize);
if (flags & JBD2_FLAG_ESCAPE) {
- *((__be32 *)bh->b_data) =
+ *((__be32 *)nbh->b_data) =
cpu_to_be32(JBD2_MAGIC_NUMBER);
}

_

Patches currently in -mm which might be from [email protected] are

jbd-correctly-unescape-journal-data-blocks.patch
jbd2-correctly-unescape-journal-data-blocks.patch
jbd2-only-create-debugfs-and-stats-entries-if-cache-initialisation-is-successful.patch