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f2fs: fix crc endian conversion
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While calculating CRC for the checkpoint block, we use __u32, but when storing
the crc value to the disk, we use __le32.

Let's fix the inconsistency.

Reported-and-Tested-by: Oded Gabbay <ogabbay@advaoptical.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
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Jaegeuk Kim committed Jul 1, 2013
1 parent 696c018 commit 7e586fa
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Showing 2 changed files with 21 additions and 10 deletions.
12 changes: 6 additions & 6 deletions fs/f2fs/checkpoint.c
Original file line number Diff line number Diff line change
Expand Up @@ -357,8 +357,8 @@ static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
unsigned long blk_size = sbi->blocksize;
struct f2fs_checkpoint *cp_block;
unsigned long long cur_version = 0, pre_version = 0;
unsigned int crc = 0;
size_t crc_offset;
__u32 crc = 0;

/* Read the 1st cp block in this CP pack */
cp_page_1 = get_meta_page(sbi, cp_addr);
Expand All @@ -369,7 +369,7 @@ static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
if (crc_offset >= blk_size)
goto invalid_cp1;

crc = *(unsigned int *)((unsigned char *)cp_block + crc_offset);
crc = le32_to_cpu(*((__u32 *)((unsigned char *)cp_block + crc_offset)));
if (!f2fs_crc_valid(crc, cp_block, crc_offset))
goto invalid_cp1;

Expand All @@ -384,7 +384,7 @@ static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
if (crc_offset >= blk_size)
goto invalid_cp2;

crc = *(unsigned int *)((unsigned char *)cp_block + crc_offset);
crc = le32_to_cpu(*((__u32 *)((unsigned char *)cp_block + crc_offset)));
if (!f2fs_crc_valid(crc, cp_block, crc_offset))
goto invalid_cp2;

Expand Down Expand Up @@ -648,7 +648,7 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
block_t start_blk;
struct page *cp_page;
unsigned int data_sum_blocks, orphan_blocks;
unsigned int crc32 = 0;
__u32 crc32 = 0;
void *kaddr;
int i;

Expand Down Expand Up @@ -717,8 +717,8 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));

crc32 = f2fs_crc32(ckpt, le32_to_cpu(ckpt->checksum_offset));
*(__le32 *)((unsigned char *)ckpt +
le32_to_cpu(ckpt->checksum_offset))
*((__le32 *)((unsigned char *)ckpt +
le32_to_cpu(ckpt->checksum_offset)))
= cpu_to_le32(crc32);

start_blk = __start_cp_addr(sbi);
Expand Down
19 changes: 15 additions & 4 deletions fs/f2fs/f2fs.h
Original file line number Diff line number Diff line change
Expand Up @@ -47,14 +47,25 @@ struct f2fs_mount_info {
unsigned int opt;
};

static inline __u32 f2fs_crc32(void *buff, size_t len)
#define CRCPOLY_LE 0xedb88320

static inline __u32 f2fs_crc32(void *buf, size_t len)
{
return crc32_le(F2FS_SUPER_MAGIC, buff, len);
unsigned char *p = (unsigned char *)buf;
__u32 crc = F2FS_SUPER_MAGIC;
int i;

while (len--) {
crc ^= *p++;
for (i = 0; i < 8; i++)
crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
}
return crc;
}

static inline bool f2fs_crc_valid(__u32 blk_crc, void *buff, size_t buff_size)
static inline bool f2fs_crc_valid(__u32 blk_crc, void *buf, size_t buf_size)
{
return f2fs_crc32(buff, buff_size) == blk_crc;
return f2fs_crc32(buf, buf_size) == blk_crc;
}

/*
Expand Down

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