Hello,
I have been experimenting this issue: https://www.spinics.net/lists/linux-ext4/msg86259.html, on a 5.15 kernel.
This issue caused by 5c48a7df9149 ("ext4: fix an use-after-free issue about data=journal writeback mode") is affecting ext4 users with data=journal on all stable kernels.
Jan proposed a fix here https://www.spinics.net/lists/linux-ext4/msg87054.html which solves the situation for me.
Now this fix is not upstream because the data journaling support has been rewritten. As suggested by Jan, that would mean that we could either backport the following patches from upstream:
bd159398a2d2 ("jdb2: Don't refuse invalidation of already invalidated buffers") d84c9ebdac1e ("ext4: Mark pages with journalled data dirty") 265e72efa99f ("ext4: Keep pages with journalled data dirty") 5e1bdea6391d ("ext4: Clear dirty bit from pages without data to write") 1f1a55f0bf06 ("ext4: Commit transaction before writing back pages in data=journal mode") e360c6ed7274 ("ext4: Drop special handling of journalled data from ext4_sync_file()") c000dfec7e88 ("ext4: Drop special handling of journalled data from extent shifting operations") 783ae448b7a2 ("ext4: Fix special handling of journalled data from extent zeroing") 56c2a0e3d90d ("ext4: Drop special handling of journalled data from ext4_evict_inode()") 7c375870fdc5 ("ext4: Drop special handling of journalled data from ext4_quota_on()") 951cafa6b80e ("ext4: Simplify handling of journalled data in ext4_bmap()") ab382539adcb ("ext4: Update comment in mpage_prepare_extent_to_map()") d0ab8368c175 ("Revert "ext4: Fix warnings when freezing filesystem with journaled data"") 1077b2d53ef5 ("ext4: fix fsync for non-directories")
Or apply the proposed, attached patch. Do you think that would be an option?
Thanks,
Mathieu
On Wed, Oct 04, 2023 at 11:37:22AM +0200, Mathieu Othacehe wrote:
Hello,
I have been experimenting this issue: https://www.spinics.net/lists/linux-ext4/msg86259.html, on a 5.15 kernel.
This issue caused by 5c48a7df9149 ("ext4: fix an use-after-free issue about data=journal writeback mode") is affecting ext4 users with data=journal on all stable kernels.
Jan proposed a fix here https://www.spinics.net/lists/linux-ext4/msg87054.html which solves the situation for me.
Now this fix is not upstream because the data journaling support has been rewritten. As suggested by Jan, that would mean that we could either backport the following patches from upstream:
bd159398a2d2 ("jdb2: Don't refuse invalidation of already invalidated buffers") d84c9ebdac1e ("ext4: Mark pages with journalled data dirty") 265e72efa99f ("ext4: Keep pages with journalled data dirty") 5e1bdea6391d ("ext4: Clear dirty bit from pages without data to write") 1f1a55f0bf06 ("ext4: Commit transaction before writing back pages in data=journal mode") e360c6ed7274 ("ext4: Drop special handling of journalled data from ext4_sync_file()") c000dfec7e88 ("ext4: Drop special handling of journalled data from extent shifting operations") 783ae448b7a2 ("ext4: Fix special handling of journalled data from extent zeroing") 56c2a0e3d90d ("ext4: Drop special handling of journalled data from ext4_evict_inode()") 7c375870fdc5 ("ext4: Drop special handling of journalled data from ext4_quota_on()") 951cafa6b80e ("ext4: Simplify handling of journalled data in ext4_bmap()") ab382539adcb ("ext4: Update comment in mpage_prepare_extent_to_map()") d0ab8368c175 ("Revert "ext4: Fix warnings when freezing filesystem with journaled data"") 1077b2d53ef5 ("ext4: fix fsync for non-directories")
Or apply the proposed, attached patch. Do you think that would be an option?
Backporting the series would be ideal. Is this only for the 5.15 kernel?
On Wed, Oct 04, 2023 at 06:10:16AM -0400, Sasha Levin wrote:
On Wed, Oct 04, 2023 at 11:37:22AM +0200, Mathieu Othacehe wrote:
bd159398a2d2 ("jdb2: Don't refuse invalidation of already invalidated buffers") d84c9ebdac1e ("ext4: Mark pages with journalled data dirty") 265e72efa99f ("ext4: Keep pages with journalled data dirty") 5e1bdea6391d ("ext4: Clear dirty bit from pages without data to write") 1f1a55f0bf06 ("ext4: Commit transaction before writing back pages in data=journal mode") e360c6ed7274 ("ext4: Drop special handling of journalled data from ext4_sync_file()") c000dfec7e88 ("ext4: Drop special handling of journalled data from extent shifting operations") 783ae448b7a2 ("ext4: Fix special handling of journalled data from extent zeroing") 56c2a0e3d90d ("ext4: Drop special handling of journalled data from ext4_evict_inode()") 7c375870fdc5 ("ext4: Drop special handling of journalled data from ext4_quota_on()") 951cafa6b80e ("ext4: Simplify handling of journalled data in ext4_bmap()") ab382539adcb ("ext4: Update comment in mpage_prepare_extent_to_map()") d0ab8368c175 ("Revert "ext4: Fix warnings when freezing filesystem with journaled data"") 1077b2d53ef5 ("ext4: fix fsync for non-directories")
Or apply the proposed, attached patch. Do you think that would be an option?
Backporting the series would be ideal. Is this only for the 5.15 kernel?
If we're going to backport all of these patches, I'd really would like to see a full regression test run, using something like:
gce-xfstests ltm -c ext4/all -g auto
before and after applying all of these patches, to make sure there are no regression.
(or you can "kvm-xfstests -c ext4/all -g auto" but be prepared for it to take over 24 hours of run time. With gce-xfstesets we start a dozen VM's in parallel so it finishes in about 2.5 hours. See https://thunk.org/gce-xfstests for more information.)
If you someone who does the backports can send me a pointer to a git branch, I can run the tests for you, if that would be helpful.
Thanks!!
- Ted
Hello!
On Thu 05-10-23 09:08:50, Mathieu Othacehe wrote:
Backporting the series would be ideal. Is this only for the 5.15 kernel?
OK. I spotted it on a 5.15 but as far as I understand, this affects all stables with 5c48a7df9149, i.e all stables. Is that correct Jan?
Yes, that is correct. Also I have realized that before patches I've already mentioned are applicable, you will also need to pick up:
9462f770eda8 ("ext4: Update stale comment about write constraints") c8e8e16dbbf0 ("ext4: Use nr_to_write directly in mpage_prepare_extent_to_map()") 3f5d30636d2a ("ext4: Mark page for delayed dirtying only if it is pinned") f1496362e9d7 ("ext4: Don't unlock page in ext4_bio_write_page()") eaf2ca10ca4b ("ext4: Move page unlocking out of mpage_submit_page()") d8be7607de03 ("ext4: Move mpage_page_done() calls after error handling") 3f079114bf52 ("ext4: Convert data=journal writeback to use ext4_writepages()") e6c28a26b799 ("ext4: Fix warnings when freezing filesystem with journaled data") This commit actually gets reverted in the series of patches I have already mentioned.
So sadly the backport is even larger than what I originally thought.
Honza
linux-stable-mirror@lists.linaro.org
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Jan Kara -
Mathieu Othacehe -
Sasha Levin -
Theodore Ts'o