ACK: [SRU][Jammy/Lunar][PATCH 0/1] CVE-2023-2898

[Tim Gardner]

On 8/1/23 4:08 PM, Yuxuan Luo wrote:
> [Impact]
> There is a null-pointer-dereference flaw found in f2fs_write_end_io in
> fs/f2fs/data.c in the Linux kernel. This flaw allows a local privileged
> user to cause a denial of service problem.
> 
> [Backport]
> It is a clean cherry pick for Lunar.
> For Jammy, conflicts in `gc.c` requires e4544b63a7ee (“f2fs: move f2fs to use
> reader-unfair rwsems”); however, since the part related to the fix
> commit is merely renaming, it is possible to ignore this commit.
> 
> [Test]
> Smoke tested on Lunar.
> 
> ```bash
> # apt-get install f2fs-tools -y
> # modprobe f2fs
> # modprobe null_blk gb=2 memory_backed=1 discard=1 # discard option is
> 						   # not available in Jammy
> # mkdir /mnt/f2fs
> # mkfs.f2fs -l label /dev/nullb0
> # mount -t f2fs /dev/nullb0 /mnt/f2fs
> # echo "hello" | sudo tee /mnt/f2fs/test
> $ cat /mnt/f2fs/test
> ```
> 
> Compile and boot tested on Jammy.
> 
> [Potential Regression]
> Expect low regression potential.
> 
> Chao Yu (1):
>    f2fs: fix to avoid NULL pointer dereference f2fs_write_end_io()
> 
>   fs/f2fs/f2fs.h |  2 +-
>   fs/f2fs/file.c |  2 +-
>   fs/f2fs/gc.c   | 21 ++++++++++++++++++---
>   3 files changed, 20 insertions(+), 5 deletions(-)
> 
Acked-by: Tim Gardner <tim.gardner at canonical.com>
-- 
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Tim Gardner
Canonical, Inc