The patch titled Subject: nilfs2: fix kernel bug due to missing clearing of checked flag has been added to the -mm mm-hotfixes-unstable branch. Its filename is nilfs2-fix-kernel-bug-due-to-missing-clearing-of-checked-flag.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nilfs2-fix-kernel-bug-due-to-missing-clearing-of-checked-flag.patch This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx> Subject: nilfs2: fix kernel bug due to missing clearing of checked flag Date: Fri, 18 Oct 2024 04:33:10 +0900 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. Link: https://lkml.kernel.org/r/20241017193359.5051-1-konishi.ryusuke@xxxxxxxxx Fixes: 8c26c4e2694a ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption") Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx> Reported-by: syzbot+d6ca2daf692c7a82f959@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=d6ca2daf692c7a82f959 Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/nilfs2/page.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/nilfs2/page.c~nilfs2-fix-kernel-bug-due-to-missing-clearing-of-checked-flag +++ a/fs/nilfs2/page.c @@ -401,6 +401,7 @@ void nilfs_clear_folio_dirty(struct foli folio_clear_uptodate(folio); folio_clear_mappedtodisk(folio); + folio_clear_checked(folio); head = folio_buffers(folio); if (head) { _ Patches currently in -mm which might be from konishi.ryusuke@xxxxxxxxx are nilfs2-fix-kernel-bug-due-to-missing-clearing-of-buffer-delay-flag.patch nilfs2-fix-kernel-bug-due-to-missing-clearing-of-checked-flag.patch