ACK+Cmnt: [SRU][B][PATCH 1/2] f2fs: fix wrong total_sections check and fsmeta check

[Luke Nowakowski-Krijger]

Hey Thadeu,

It looks like the git cherry-pick happened to auto merge it in the correct
way and I did not question it :)

Thanks for the review,

- Luke

On Thu, Sep 30, 2021 at 12:06 PM Thadeu Lima de Souza Cascardo <
cascardo at canonical.com> wrote:

> On Thu, Sep 30, 2021 at 11:28:46AM -0700, Luke Nowakowski-Krijger wrote:
> > From: Wang Xiaojun <wangxiaojun11 at huawei.com>
> >
> > Meta area is not included in section_count computation.
> > So the minimum number of total_sections is 1 meanwhile it cannot be
> > greater than segment_count_main.
> >
> > The minimum number of meta segments is 8 (SB + 2 (CP + SIT + NAT) + SSA).
> >
> > Signed-off-by: Wang Xiaojun <wangxiaojun11 at huawei.com>
> > Reviewed-by: Chao Yu <yuchao0 at huawei.com>
> > Signed-off-by: Jaegeuk Kim <jaegeuk at kernel.org>
> > (cherry-picked from f99ba9add67ce63eca3fe68a3d5e9996cd2c33b5)
> > CVE-2019-19449
>
> Hey, Luke.
>
> Didn't this commit require a conflict fix due to f2fs_msg vs
> f2fs_info/f2fs_err
> as well? It looks like it didn't, as I just tested it.
>
> Again, thanks for the work.
>
> Acked-by: Thadeu Lima de Souza Cascardo <cascardo at canonical.com>
>
> > Signed-off-by: Luke Nowakowski-Krijger <
> luke.nowakowskikrijger at canonical.com>
> > ---
> >  fs/f2fs/segment.h | 1 +
> >  fs/f2fs/super.c   | 8 ++++----
> >  2 files changed, 5 insertions(+), 4 deletions(-)
> >
> > diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
> > index 135e14f9bfbd..dbc9549ef0a4 100644
> > --- a/fs/f2fs/segment.h
> > +++ b/fs/f2fs/segment.h
> > @@ -19,6 +19,7 @@
> >  #define DEF_MAX_RECLAIM_PREFREE_SEGMENTS     4096    /* 8GB in maximum
> */
> >
> >  #define F2FS_MIN_SEGMENTS    9 /* SB + 2 (CP + SIT + NAT) + SSA + MAIN
> */
> > +#define F2FS_MIN_META_SEGMENTS       8 /* SB + 2 (CP + SIT + NAT) + SSA
> */
> >
> >  /* L: Logical segment # in volume, R: Relative segment # in main area */
> >  #define GET_L2R_SEGNO(free_i, segno) ((segno) - (free_i)->start_segno)
> > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> > index d51f78df2c57..9eba35db374c 100644
> > --- a/fs/f2fs/super.c
> > +++ b/fs/f2fs/super.c
> > @@ -1970,7 +1970,7 @@ static inline bool
> sanity_check_area_boundary(struct f2fs_sb_info *sbi,
> >  static int sanity_check_raw_super(struct f2fs_sb_info *sbi,
> >                               struct buffer_head *bh)
> >  {
> > -     block_t segment_count, segs_per_sec, secs_per_zone;
> > +     block_t segment_count, segs_per_sec, secs_per_zone,
> segment_count_main;
> >       block_t total_sections, blocks_per_seg;
> >       struct f2fs_super_block *raw_super = (struct f2fs_super_block *)
> >                                       (bh->b_data + F2FS_SUPER_OFFSET);
> > @@ -2029,6 +2029,7 @@ static int sanity_check_raw_super(struct
> f2fs_sb_info *sbi,
> >       }
> >
> >       segment_count = le32_to_cpu(raw_super->segment_count);
> > +     segment_count_main = le32_to_cpu(raw_super->segment_count_main);
> >       segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
> >       secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
> >       total_sections = le32_to_cpu(raw_super->section_count);
> > @@ -2044,8 +2045,7 @@ static int sanity_check_raw_super(struct
> f2fs_sb_info *sbi,
> >               return -EFSCORRUPTED;
> >       }
> >
> > -     if (total_sections > segment_count ||
> > -                     total_sections < F2FS_MIN_SEGMENTS ||
> > +     if (total_sections > segment_count_main || total_sections < 1 ||
> >                       segs_per_sec > segment_count || !segs_per_sec) {
> >               f2fs_msg(sb, KERN_INFO,
> >                       "Invalid segment/section count (%u, %u x %u)",
> > @@ -2139,7 +2139,7 @@ int sanity_check_ckpt(struct f2fs_sb_info *sbi)
> >       ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
> >       reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
> >
> > -     if (unlikely(fsmeta < F2FS_MIN_SEGMENTS ||
> > +     if (unlikely(fsmeta < F2FS_MIN_META_SEGMENTS ||
> >                       ovp_segments == 0 || reserved_segments == 0)) {
> >               f2fs_msg(sbi->sb, KERN_ERR,
> >                       "Wrong layout: check mkfs.f2fs version");
> > --
> > 2.30.2
> >
> >
> > --
> > kernel-team mailing list
> > kernel-team at lists.ubuntu.com
> > https://lists.ubuntu.com/mailman/listinfo/kernel-team
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.ubuntu.com/archives/kernel-team/attachments/20210930/b25303de/attachment.html>