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FAILED: Patch "nilfs2: fix kernel bug due to missing clearing of checked flag" failed to apply to v6.6-stable tree

PATCH Sasha Levin 3 participants 3 messages Nov 6, 2024

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Sasha Levin

author maintainer
#0 lore raw

The patch below does not apply to the v6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 41e192ad2779cae0102879612dfe46726e4396aa Mon Sep 17 00:00:00 2001
From: Ryusuke Konishi <[email protected]>
Date: Fri, 18 Oct 2024 04:33:10 +0900
Subject: [PATCH] nilfs2: fix kernel bug due to missing clearing of checked
flag

Syzbot reported that in directory operations after nilfs2 detects filesystem corruption and degrades to read-only, __block_write_begin_int(), which is called to prepare block writes, may fail the BUG_ON check for accesses exceeding the folio/page size, triggering a kernel bug.

This was found to be because the "checked" flag of a page/folio was not cleared when it was discarded by nilfs2's own routine, which causes the sanity check of directory entries to be skipped when the directory page/folio is reloaded. So, fix that.

This was necessary when the use of nilfs2's own page discard routine was applied to more than just metadata files.

Fixes 8c26c4e2694a ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption")
Reported-by [email protected]
---
 fs/nilfs2/page.c | 1 +
 1 file changed, 1 insertion(+)
fs/nilfs2/page.c +1 -0
index 5436eb0424bd1..10def4b559956 100644
@@ -401,6 +401,7 @@ void nilfs_clear_folio_dirty(struct folio *folio)
 
 	folio_clear_uptodate(folio);
 	folio_clear_mappedtodisk(folio);
+	folio_clear_checked(folio);
 
 	head = folio_buffers(folio);
 	if (head) {
Signature · 1 line
2.43.0
maintainer
#1 lore raw

Hi Sasha

About 6 hours ago, I posted an adjusted patch to the list (and to Greg) that allows for backporting of this patch to 6.6-stable and earlier.

The patch is titled "[PATCH 4.19 5.4 5.10 5.15 6.1 6.6] nilfs2: fix kernel bug due to missing clearing of checked flag".

(or https://lkml.kernel.org/r/[email protected] )

Normally, Greg would pick up the adjusted patch and apply it, and it would be backported without any problems, but if the backport of the adjusted patch I requested has been rejected, I would like to ask for your confirmation.

If it is a misunderstanding, I will wait for Greg's work, but is the process different from usual?

Thank you in advance.

Ryusuke Konishi

Quoted 60 lines · Sasha Levin

The patch below does not apply to the v6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 41e192ad2779cae0102879612dfe46726e4396aa Mon Sep 17 00:00:00 2001
From: Ryusuke Konishi <[email protected]>
Date: Fri, 18 Oct 2024 04:33:10 +0900
Subject: [PATCH] nilfs2: fix kernel bug due to missing clearing of checked
flag

Syzbot reported that in directory operations after nilfs2 detects filesystem corruption and degrades to read-only, __block_write_begin_int(), which is called to prepare block writes, may fail the BUG_ON check for accesses exceeding the folio/page size, triggering a kernel bug.

This was found to be because the "checked" flag of a page/folio was not cleared when it was discarded by nilfs2's own routine, which causes the sanity check of directory entries to be skipped when the directory page/folio is reloaded. So, fix that.

This was necessary when the use of nilfs2's own page discard routine was applied to more than just metadata files.

Fixes 8c26c4e2694a ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption")
Reported-by [email protected]
---
 fs/nilfs2/page.c | 1 +
 1 file changed, 1 insertion(+)
fs/nilfs2/page.c +1 -1
index 5436eb0424bd1..10def4b559956 100644
@@ -401,6 +401,7 @@ void nilfs_clear_folio_dirty(struct folio *folio)
 
        folio_clear_uptodate(folio);
        folio_clear_mappedtodisk(folio);
+       folio_clear_checked(folio);
 
        head = folio_buffers(folio);
        if (head) {
--

2.43.0

#2 lore raw
Quoted 11 lines · Ryusuke Konishi

Hi Sasha

About 6 hours ago, I posted an adjusted patch to the list (and to Greg) that allows for backporting of this patch to 6.6-stable and earlier.

The patch is titled "[PATCH 4.19 5.4 5.10 5.15 6.1 6.6] nilfs2: fix kernel bug due to missing clearing of checked flag".

(or https://lkml.kernel.org/r/[email protected] )

Quoted 7 lines

Normally, Greg would pick up the adjusted patch and apply it, and it would be backported without any problems, but if the backport of the adjusted patch I requested has been rejected, I would like to ask for your confirmation.

If it is a misunderstanding, I will wait for Greg's work, but is the process different from usual?

I got it now, thanks!

greg k-h