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Date: Mon, 14 Dec 2015 16:55:38 -0800
From: Jaegeuk Kim <jaegeuk@...nel.org>
To: Chao Yu <chao2.yu@...sung.com>
Cc: linux-f2fs-devel@...ts.sourceforge.net,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] f2fs: do more integrity verification for superblock
Hi Chao,
I also got superblock failure.
It seems that your patch doesn't handle correctly if segment0_blkaddr is not
zero.
Please see below.
On Fri, Dec 11, 2015 at 04:09:23PM +0800, Chao Yu wrote:
> Do more sanity check for superblock during ->mount.
>
> Signed-off-by: Chao Yu <chao2.yu@...sung.com>
> ---
> fs/f2fs/super.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 98 insertions(+)
>
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 5434186..624fc2c 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -926,6 +926,79 @@ static loff_t max_file_size(unsigned bits)
> return result;
> }
>
> +static inline bool sanity_check_area_boundary(struct super_block *sb,
> + struct f2fs_super_block *raw_super)
> +{
> + u32 segment0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
> + u32 cp_blkaddr = le32_to_cpu(raw_super->cp_blkaddr);
> + u32 sit_blkaddr = le32_to_cpu(raw_super->sit_blkaddr);
> + u32 nat_blkaddr = le32_to_cpu(raw_super->nat_blkaddr);
> + u32 ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
> + u32 main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
> + u32 segment_count_ckpt = le32_to_cpu(raw_super->segment_count_ckpt);
> + u32 segment_count_sit = le32_to_cpu(raw_super->segment_count_sit);
> + u32 segment_count_nat = le32_to_cpu(raw_super->segment_count_nat);
> + u32 segment_count_ssa = le32_to_cpu(raw_super->segment_count_ssa);
> + u32 segment_count_main = le32_to_cpu(raw_super->segment_count_main);
> + u32 segment_count = le32_to_cpu(raw_super->segment_count);
> + u32 log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
> +
> + if (segment0_blkaddr != cp_blkaddr) {
> + f2fs_msg(sb, KERN_INFO,
> + "Mismatch start address, segment0(%u) cp_blkaddr(%u)",
> + segment0_blkaddr, cp_blkaddr);
> + return true;
> + }
> +
> + if (cp_blkaddr + (segment_count_ckpt << log_blocks_per_seg) !=
> + sit_blkaddr) {
> + f2fs_msg(sb, KERN_INFO,
> + "Wrong CP boundary, start(%u) end(%u) blocks(%u)",
> + cp_blkaddr, sit_blkaddr,
> + segment_count_ckpt << log_blocks_per_seg);
> + return true;
> + }
> +
> + if (sit_blkaddr + (segment_count_sit << log_blocks_per_seg) !=
> + nat_blkaddr) {
> + f2fs_msg(sb, KERN_INFO,
> + "Wrong SIT boundary, start(%u) end(%u) blocks(%u)",
> + sit_blkaddr, nat_blkaddr,
> + segment_count_sit << log_blocks_per_seg);
> + return true;
> + }
> +
> + if (nat_blkaddr + (segment_count_nat << log_blocks_per_seg) !=
> + ssa_blkaddr) {
> + f2fs_msg(sb, KERN_INFO,
> + "Wrong NAT boundary, start(%u) end(%u) blocks(%u)",
> + nat_blkaddr, ssa_blkaddr,
> + segment_count_nat << log_blocks_per_seg);
> + return true;
> + }
> +
> + if (ssa_blkaddr + (segment_count_ssa << log_blocks_per_seg) !=
> + main_blkaddr) {
> + f2fs_msg(sb, KERN_INFO,
> + "Wrong SSA boundary, start(%u) end(%u) blocks(%u)",
> + ssa_blkaddr, main_blkaddr,
> + segment_count_ssa << log_blocks_per_seg);
> + return true;
> + }
> +
> + if (main_blkaddr + (segment_count_main << log_blocks_per_seg) !=
> + (segment_count + 1) << log_blocks_per_seg) {
This should be
segment_count << log_blocks_per_seg + segment0_blkaddr) {
=========================================================================
'- main_blkaddr
`- segment0_blkaddr
|-------------- segment_count_main ----------|
|-------------------------- segment_count --------------------------|
Thanks,
> + f2fs_msg(sb, KERN_INFO,
> + "Wrong MAIN_AREA boundary, start(%u) end(%u) blocks(%u)",
> + main_blkaddr,
> + (segment_count + 1) << log_blocks_per_seg,
> + segment_count_main << log_blocks_per_seg);
> + return true;
> + }
> +
> + return false;
> +}
> +
> static int sanity_check_raw_super(struct super_block *sb,
> struct f2fs_super_block *raw_super)
> {
> @@ -955,6 +1028,14 @@ static int sanity_check_raw_super(struct super_block *sb,
> return 1;
> }
>
> + /* check log blocks per segment */
> + if (le32_to_cpu(raw_super->log_blocks_per_seg) != 9) {
> + f2fs_msg(sb, KERN_INFO,
> + "Invalid log blocks per segment (%u)\n",
> + le32_to_cpu(raw_super->log_blocks_per_seg));
> + return 1;
> + }
> +
> /* Currently, support 512/1024/2048/4096 bytes sector size */
> if (le32_to_cpu(raw_super->log_sectorsize) >
> F2FS_MAX_LOG_SECTOR_SIZE ||
> @@ -973,6 +1054,23 @@ static int sanity_check_raw_super(struct super_block *sb,
> le32_to_cpu(raw_super->log_sectorsize));
> return 1;
> }
> +
> + /* check reserved ino info */
> + if (le32_to_cpu(raw_super->node_ino) != 1 ||
> + le32_to_cpu(raw_super->meta_ino) != 2 ||
> + le32_to_cpu(raw_super->root_ino) != 3) {
> + f2fs_msg(sb, KERN_INFO,
> + "Invalid Fs Meta Ino: node(%u) meta(%u) root(%u)",
> + le32_to_cpu(raw_super->node_ino),
> + le32_to_cpu(raw_super->meta_ino),
> + le32_to_cpu(raw_super->root_ino));
> + return 1;
> + }
> +
> + /* check CP/SIT/NAT/SSA/MAIN_AREA area boundary */
> + if (sanity_check_area_boundary(sb, raw_super))
> + return 1;
> +
> return 0;
> }
>
> --
> 2.6.3
>
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