* [PATCH 2/4 v3] exfat: separate the boot sector analysis
2020-05-29 10:14 ` [PATCH 1/4 v3] exfat: redefine PBR as boot_sector Tetsuhiro Kohada
@ 2020-05-29 10:14 ` Tetsuhiro Kohada
2020-06-01 12:19 ` Sungjong Seo
2020-05-29 10:14 ` [PATCH 3/4 v3] exfat: add boot region verification Tetsuhiro Kohada
` (2 subsequent siblings)
3 siblings, 1 reply; 7+ messages in thread
From: Tetsuhiro Kohada @ 2020-05-29 10:14 UTC (permalink / raw)
To: kohada.t2
Cc: kohada.tetsuhiro, mori.takahiro, motai.hirotaka, Namjae Jeon,
Sungjong Seo, linux-fsdevel, linux-kernel
Separate the boot sector analysis to read_boot_sector().
And add a check for the fs_name field.
Furthermore, add a strict consistency check, because overlapping areas
can cause serious corruption.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
---
Changes in v2:
- rebase with patch 'optimize dir-cache' applied
Changes in v3:
- add a check for the fs_name field
fs/exfat/exfat_raw.h | 2 +
fs/exfat/super.c | 97 ++++++++++++++++++++++++--------------------
2 files changed, 56 insertions(+), 43 deletions(-)
diff --git a/fs/exfat/exfat_raw.h b/fs/exfat/exfat_raw.h
index 07f74190df44..350ce59cc324 100644
--- a/fs/exfat/exfat_raw.h
+++ b/fs/exfat/exfat_raw.h
@@ -10,11 +10,13 @@
#define BOOT_SIGNATURE 0xAA55
#define EXBOOT_SIGNATURE 0xAA550000
+#define STR_EXFAT "EXFAT " /* size should be 8 */
#define EXFAT_MAX_FILE_LEN 255
#define VOL_CLEAN 0x0000
#define VOL_DIRTY 0x0002
+#define ERR_MEDIUM 0x0004
#define EXFAT_EOF_CLUSTER 0xFFFFFFFFu
#define EXFAT_BAD_CLUSTER 0xFFFFFFF7u
diff --git a/fs/exfat/super.c b/fs/exfat/super.c
index e60d28e73ff0..6a1330be5a9a 100644
--- a/fs/exfat/super.c
+++ b/fs/exfat/super.c
@@ -366,25 +366,20 @@ static int exfat_read_root(struct inode *inode)
return 0;
}
-static struct boot_sector *exfat_read_boot_with_logical_sector(
- struct super_block *sb)
+static int exfat_calibrate_blocksize(struct super_block *sb, int logical_sect)
{
struct exfat_sb_info *sbi = EXFAT_SB(sb);
- struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
- unsigned short logical_sect = 0;
-
- logical_sect = 1 << p_boot->sect_size_bits;
if (!is_power_of_2(logical_sect) ||
logical_sect < 512 || logical_sect > 4096) {
exfat_err(sb, "bogus logical sector size %u", logical_sect);
- return NULL;
+ return -EIO;
}
if (logical_sect < sb->s_blocksize) {
exfat_err(sb, "logical sector size too small for device (logical sector size = %u)",
logical_sect);
- return NULL;
+ return -EIO;
}
if (logical_sect > sb->s_blocksize) {
@@ -394,24 +389,20 @@ static struct boot_sector *exfat_read_boot_with_logical_sector(
if (!sb_set_blocksize(sb, logical_sect)) {
exfat_err(sb, "unable to set blocksize %u",
logical_sect);
- return NULL;
+ return -EIO;
}
sbi->boot_bh = sb_bread(sb, 0);
if (!sbi->boot_bh) {
exfat_err(sb, "unable to read boot sector (logical sector size = %lu)",
sb->s_blocksize);
- return NULL;
+ return -EIO;
}
-
- p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
}
- return p_boot;
+ return 0;
}
-/* mount the file system volume */
-static int __exfat_fill_super(struct super_block *sb)
+static int exfat_read_boot_sector(struct super_block *sb)
{
- int ret;
struct boot_sector *p_boot;
struct exfat_sb_info *sbi = EXFAT_SB(sb);
@@ -424,51 +415,41 @@ static int __exfat_fill_super(struct super_block *sb)
exfat_err(sb, "unable to read boot sector");
return -EIO;
}
-
- /* PRB is read */
p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
/* check the validity of BOOT */
if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) {
exfat_err(sb, "invalid boot record signature");
- ret = -EINVAL;
- goto free_bh;
+ return -EINVAL;
}
-
- /* check logical sector size */
- p_boot = exfat_read_boot_with_logical_sector(sb);
- if (!p_boot) {
- ret = -EIO;
- goto free_bh;
+ if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) {
+ exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable */
+ return -EINVAL;
}
/*
- * res_zero field must be filled with zero to prevent mounting
+ * must_be_zero field must be filled with zero to prevent mounting
* from FAT volume.
*/
- if (memchr_inv(p_boot->must_be_zero, 0,
- sizeof(p_boot->must_be_zero))) {
- ret = -EINVAL;
- goto free_bh;
- }
+ if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot->must_be_zero)))
+ return -EINVAL;
- p_boot = (struct boot_sector *)p_boot;
- if (!p_boot->num_fats) {
+ if (p_boot->num_fats != 1 && p_boot->num_fats != 2) {
exfat_err(sb, "bogus number of FAT structure");
- ret = -EINVAL;
- goto free_bh;
+ return -EINVAL;
}
sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits;
sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits;
- sbi->cluster_size_bits = sbi->sect_per_clus_bits + sb->s_blocksize_bits;
+ sbi->cluster_size_bits = p_boot->sect_per_clus_bits +
+ p_boot->sect_size_bits;
sbi->cluster_size = 1 << sbi->cluster_size_bits;
sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length);
sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset);
- sbi->FAT2_start_sector = p_boot->num_fats == 1 ?
- sbi->FAT1_start_sector :
- sbi->FAT1_start_sector + sbi->num_FAT_sectors;
+ sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset);
+ if (p_boot->num_fats == 2)
+ sbi->FAT2_start_sector += sbi->num_FAT_sectors;
sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset);
sbi->num_sectors = le64_to_cpu(p_boot->vol_length);
/* because the cluster index starts with 2 */
@@ -483,15 +464,45 @@ static int __exfat_fill_super(struct super_block *sb)
sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;
sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED;
- if (le16_to_cpu(p_boot->vol_flags) & VOL_DIRTY) {
- sbi->vol_flag |= VOL_DIRTY;
- exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck.");
+ /* check consistencies */
+ if (sbi->num_FAT_sectors << p_boot->sect_size_bits <
+ sbi->num_clusters * 4) {
+ exfat_err(sb, "bogus fat length");
+ return -EINVAL;
+ }
+ if (sbi->data_start_sector <
+ sbi->FAT1_start_sector + sbi->num_FAT_sectors * p_boot->num_fats) {
+ exfat_err(sb, "bogus data start sector");
+ return -EINVAL;
}
+ if (sbi->vol_flag & VOL_DIRTY)
+ exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck.");
+ if (sbi->vol_flag & ERR_MEDIUM)
+ exfat_warn(sb, "Medium has reported failures. Some data may be lost.");
/* exFAT file size is limited by a disk volume size */
sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) <<
sbi->cluster_size_bits;
+ /* check logical sector size */
+ if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits))
+ return -EIO;
+
+ return 0;
+}
+
+/* mount the file system volume */
+static int __exfat_fill_super(struct super_block *sb)
+{
+ int ret;
+ struct exfat_sb_info *sbi = EXFAT_SB(sb);
+
+ ret = exfat_read_boot_sector(sb);
+ if (ret) {
+ exfat_err(sb, "failed to read boot sector");
+ goto free_bh;
+ }
+
ret = exfat_create_upcase_table(sb);
if (ret) {
exfat_err(sb, "failed to load upcase table");
--
2.25.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* RE: [PATCH 2/4 v3] exfat: separate the boot sector analysis
2020-05-29 10:14 ` [PATCH 2/4 v3] exfat: separate the boot sector analysis Tetsuhiro Kohada
@ 2020-06-01 12:19 ` Sungjong Seo
0 siblings, 0 replies; 7+ messages in thread
From: Sungjong Seo @ 2020-06-01 12:19 UTC (permalink / raw)
To: 'Tetsuhiro Kohada'
Cc: kohada.tetsuhiro, mori.takahiro, motai.hirotaka,
'Namjae Jeon', linux-fsdevel, linux-kernel
> Separate the boot sector analysis to read_boot_sector().
> And add a check for the fs_name field.
> Furthermore, add a strict consistency check, because overlapping areas can
> cause serious corruption.
>
> Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
> ---
> Changes in v2:
> - rebase with patch 'optimize dir-cache' applied Changes in v3:
> - add a check for the fs_name field
>
> fs/exfat/exfat_raw.h | 2 +
> fs/exfat/super.c | 97 ++++++++++++++++++++++++--------------------
> 2 files changed, 56 insertions(+), 43 deletions(-)
>
> diff --git a/fs/exfat/exfat_raw.h b/fs/exfat/exfat_raw.h index
> 07f74190df44..350ce59cc324 100644
> --- a/fs/exfat/exfat_raw.h
> +++ b/fs/exfat/exfat_raw.h
> @@ -10,11 +10,13 @@
>
> #define BOOT_SIGNATURE 0xAA55
> #define EXBOOT_SIGNATURE 0xAA550000
> +#define STR_EXFAT "EXFAT " /* size should be 8 */
>
> #define EXFAT_MAX_FILE_LEN 255
>
> #define VOL_CLEAN 0x0000
> #define VOL_DIRTY 0x0002
> +#define ERR_MEDIUM 0x0004
>
> #define EXFAT_EOF_CLUSTER 0xFFFFFFFFu
> #define EXFAT_BAD_CLUSTER 0xFFFFFFF7u
> diff --git a/fs/exfat/super.c b/fs/exfat/super.c index
> e60d28e73ff0..6a1330be5a9a 100644
> --- a/fs/exfat/super.c
> +++ b/fs/exfat/super.c
> @@ -366,25 +366,20 @@ static int exfat_read_root(struct inode *inode)
> return 0;
> }
>
> -static struct boot_sector *exfat_read_boot_with_logical_sector(
> - struct super_block *sb)
> +static int exfat_calibrate_blocksize(struct super_block *sb, int
> +logical_sect)
> {
> struct exfat_sb_info *sbi = EXFAT_SB(sb);
> - struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh-
> >b_data;
> - unsigned short logical_sect = 0;
> -
> - logical_sect = 1 << p_boot->sect_size_bits;
>
> if (!is_power_of_2(logical_sect) ||
> logical_sect < 512 || logical_sect > 4096) {
> exfat_err(sb, "bogus logical sector size %u", logical_sect);
> - return NULL;
> + return -EIO;
> }
>
> if (logical_sect < sb->s_blocksize) {
> exfat_err(sb, "logical sector size too small for device
> (logical sector size = %u)",
> logical_sect);
> - return NULL;
> + return -EIO;
> }
>
> if (logical_sect > sb->s_blocksize) {
> @@ -394,24 +389,20 @@ static struct boot_sector
> *exfat_read_boot_with_logical_sector(
> if (!sb_set_blocksize(sb, logical_sect)) {
> exfat_err(sb, "unable to set blocksize %u",
> logical_sect);
> - return NULL;
> + return -EIO;
> }
> sbi->boot_bh = sb_bread(sb, 0);
> if (!sbi->boot_bh) {
> exfat_err(sb, "unable to read boot sector (logical
> sector size = %lu)",
> sb->s_blocksize);
> - return NULL;
> + return -EIO;
> }
> -
> - p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
> }
> - return p_boot;
> + return 0;
> }
>
> -/* mount the file system volume */
> -static int __exfat_fill_super(struct super_block *sb)
> +static int exfat_read_boot_sector(struct super_block *sb)
> {
> - int ret;
> struct boot_sector *p_boot;
> struct exfat_sb_info *sbi = EXFAT_SB(sb);
>
> @@ -424,51 +415,41 @@ static int __exfat_fill_super(struct super_block
*sb)
> exfat_err(sb, "unable to read boot sector");
> return -EIO;
> }
> -
> - /* PRB is read */
> p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
>
> /* check the validity of BOOT */
> if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) {
> exfat_err(sb, "invalid boot record signature");
> - ret = -EINVAL;
> - goto free_bh;
> + return -EINVAL;
> }
>
> -
> - /* check logical sector size */
> - p_boot = exfat_read_boot_with_logical_sector(sb);
> - if (!p_boot) {
> - ret = -EIO;
> - goto free_bh;
> + if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) {
> + exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable
> */
> + return -EINVAL;
> }
>
> /*
> - * res_zero field must be filled with zero to prevent mounting
> + * must_be_zero field must be filled with zero to prevent mounting
> * from FAT volume.
> */
> - if (memchr_inv(p_boot->must_be_zero, 0,
> - sizeof(p_boot->must_be_zero))) {
> - ret = -EINVAL;
> - goto free_bh;
> - }
> + if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot-
> >must_be_zero)))
> + return -EINVAL;
>
> - p_boot = (struct boot_sector *)p_boot;
> - if (!p_boot->num_fats) {
> + if (p_boot->num_fats != 1 && p_boot->num_fats != 2) {
> exfat_err(sb, "bogus number of FAT structure");
> - ret = -EINVAL;
> - goto free_bh;
> + return -EINVAL;
> }
>
> sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits;
> sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits;
> - sbi->cluster_size_bits = sbi->sect_per_clus_bits + sb-
> >s_blocksize_bits;
> + sbi->cluster_size_bits = p_boot->sect_per_clus_bits +
> + p_boot->sect_size_bits;
> sbi->cluster_size = 1 << sbi->cluster_size_bits;
> sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length);
> sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset);
> - sbi->FAT2_start_sector = p_boot->num_fats == 1 ?
> - sbi->FAT1_start_sector :
> - sbi->FAT1_start_sector + sbi->num_FAT_sectors;
> + sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset);
> + if (p_boot->num_fats == 2)
> + sbi->FAT2_start_sector += sbi->num_FAT_sectors;
> sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset);
> sbi->num_sectors = le64_to_cpu(p_boot->vol_length);
> /* because the cluster index starts with 2 */ @@ -483,15 +464,45 @@
> static int __exfat_fill_super(struct super_block *sb)
> sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;
> sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED;
>
> - if (le16_to_cpu(p_boot->vol_flags) & VOL_DIRTY) {
> - sbi->vol_flag |= VOL_DIRTY;
> - exfat_warn(sb, "Volume was not properly unmounted. Some data
> may be corrupt. Please run fsck.");
> + /* check consistencies */
> + if (sbi->num_FAT_sectors << p_boot->sect_size_bits <
> + sbi->num_clusters * 4) {
> + exfat_err(sb, "bogus fat length");
> + return -EINVAL;
> + }
> + if (sbi->data_start_sector <
> + sbi->FAT1_start_sector + sbi->num_FAT_sectors *
p_boot->num_fats)
> {
> + exfat_err(sb, "bogus data start sector");
> + return -EINVAL;
> }
> + if (sbi->vol_flag & VOL_DIRTY)
> + exfat_warn(sb, "Volume was not properly unmounted. Some data
> may be corrupt. Please run fsck.");
> + if (sbi->vol_flag & ERR_MEDIUM)
> + exfat_warn(sb, "Medium has reported failures. Some data may
> be
> +lost.");
>
> /* exFAT file size is limited by a disk volume size */
> sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS)
> <<
> sbi->cluster_size_bits;
>
> + /* check logical sector size */
> + if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits))
> + return -EIO;
> +
> + return 0;
> +}
> +
> +/* mount the file system volume */
> +static int __exfat_fill_super(struct super_block *sb) {
> + int ret;
> + struct exfat_sb_info *sbi = EXFAT_SB(sb);
> +
> + ret = exfat_read_boot_sector(sb);
> + if (ret) {
> + exfat_err(sb, "failed to read boot sector");
> + goto free_bh;
> + }
> +
> ret = exfat_create_upcase_table(sb);
> if (ret) {
> exfat_err(sb, "failed to load upcase table");
> --
> 2.25.1
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH 3/4 v3] exfat: add boot region verification
2020-05-29 10:14 ` [PATCH 1/4 v3] exfat: redefine PBR as boot_sector Tetsuhiro Kohada
2020-05-29 10:14 ` [PATCH 2/4 v3] exfat: separate the boot sector analysis Tetsuhiro Kohada
@ 2020-05-29 10:14 ` Tetsuhiro Kohada
2020-05-29 10:14 ` [PATCH 4/4 v3] exfat: standardize checksum calculation Tetsuhiro Kohada
2020-06-01 12:18 ` [PATCH 1/4 v3] exfat: redefine PBR as boot_sector Sungjong Seo
3 siblings, 0 replies; 7+ messages in thread
From: Tetsuhiro Kohada @ 2020-05-29 10:14 UTC (permalink / raw)
To: kohada.t2
Cc: kohada.tetsuhiro, mori.takahiro, motai.hirotaka, Namjae Jeon,
Sungjong Seo, linux-fsdevel, linux-kernel
Add Boot-Regions verification specified in exFAT specification.
Note that the checksum type is strongly related to the raw structure,
so the'u32 'type is used to clarify the number of bits.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
---
Changes in v2:
- rebase with patch 'optimize dir-cache' applied
- just print a warning when invalid exboot-signature detected
- print additional information when invalid boot-checksum detected
Changes in v3:
- based on '[PATCH 2/4 v3] exfat: separate the boot sector analysis'
fs/exfat/exfat_fs.h | 1 +
fs/exfat/misc.c | 14 +++++++++++++
fs/exfat/super.c | 49 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 64 insertions(+)
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index 9673e2d31045..eebbe5a84b2b 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -514,6 +514,7 @@ void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
u8 *tz, __le16 *time, __le16 *date, u8 *time_cs);
unsigned short exfat_calc_chksum_2byte(void *data, int len,
unsigned short chksum, int type);
+u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type);
void exfat_update_bh(struct super_block *sb, struct buffer_head *bh, int sync);
void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
unsigned int size, unsigned char flags);
diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c
index ab7f88b1f6d3..b82d2dd5bd7c 100644
--- a/fs/exfat/misc.c
+++ b/fs/exfat/misc.c
@@ -151,6 +151,20 @@ unsigned short exfat_calc_chksum_2byte(void *data, int len,
return chksum;
}
+u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type)
+{
+ int i;
+ u8 *c = (u8 *)data;
+
+ for (i = 0; i < len; i++, c++) {
+ if (unlikely(type == CS_BOOT_SECTOR &&
+ (i == 106 || i == 107 || i == 112)))
+ continue;
+ chksum = ((chksum << 31) | (chksum >> 1)) + *c;
+ }
+ return chksum;
+}
+
void exfat_update_bh(struct super_block *sb, struct buffer_head *bh, int sync)
{
set_bit(EXFAT_SB_DIRTY, &EXFAT_SB(sb)->s_state);
diff --git a/fs/exfat/super.c b/fs/exfat/super.c
index 6a1330be5a9a..c9bc6ad0aade 100644
--- a/fs/exfat/super.c
+++ b/fs/exfat/super.c
@@ -491,6 +491,49 @@ static int exfat_read_boot_sector(struct super_block *sb)
return 0;
}
+static int exfat_verify_boot_region(struct super_block *sb)
+{
+ struct buffer_head *bh = NULL;
+ u32 chksum = 0, *p_sig, *p_chksum;
+ int sn, i;
+
+ /* read boot sector sub-regions */
+ for (sn = 0; sn < 11; sn++) {
+ bh = sb_bread(sb, sn);
+ if (!bh)
+ return -EIO;
+
+ if (sn != 0 && sn <= 8) {
+ /* extended boot sector sub-regions */
+ p_sig = (u32 *)&bh->b_data[sb->s_blocksize - 4];
+ if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE)
+ exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x",
+ sn, le32_to_cpu(*p_sig));
+ }
+
+ chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize,
+ chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR);
+ brelse(bh);
+ }
+
+ /* boot checksum sub-regions */
+ bh = sb_bread(sb, sn);
+ if (!bh)
+ return -EIO;
+
+ for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) {
+ p_chksum = (u32 *)&bh->b_data[i];
+ if (le32_to_cpu(*p_chksum) != chksum) {
+ exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)",
+ le32_to_cpu(*p_chksum), chksum);
+ brelse(bh);
+ return -EINVAL;
+ }
+ }
+ brelse(bh);
+ return 0;
+}
+
/* mount the file system volume */
static int __exfat_fill_super(struct super_block *sb)
{
@@ -503,6 +546,12 @@ static int __exfat_fill_super(struct super_block *sb)
goto free_bh;
}
+ ret = exfat_verify_boot_region(sb);
+ if (ret) {
+ exfat_err(sb, "invalid boot region");
+ goto free_bh;
+ }
+
ret = exfat_create_upcase_table(sb);
if (ret) {
exfat_err(sb, "failed to load upcase table");
--
2.25.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 4/4 v3] exfat: standardize checksum calculation
2020-05-29 10:14 ` [PATCH 1/4 v3] exfat: redefine PBR as boot_sector Tetsuhiro Kohada
2020-05-29 10:14 ` [PATCH 2/4 v3] exfat: separate the boot sector analysis Tetsuhiro Kohada
2020-05-29 10:14 ` [PATCH 3/4 v3] exfat: add boot region verification Tetsuhiro Kohada
@ 2020-05-29 10:14 ` Tetsuhiro Kohada
2020-06-01 12:20 ` Sungjong Seo
2020-06-01 12:18 ` [PATCH 1/4 v3] exfat: redefine PBR as boot_sector Sungjong Seo
3 siblings, 1 reply; 7+ messages in thread
From: Tetsuhiro Kohada @ 2020-05-29 10:14 UTC (permalink / raw)
To: kohada.t2
Cc: kohada.tetsuhiro, mori.takahiro, motai.hirotaka, Namjae Jeon,
Sungjong Seo, linux-fsdevel, linux-kernel
To clarify that it is a 16-bit checksum, the parts related to the 16-bit
checksum are renamed and change type to u16.
Furthermore, replace checksum calculation in exfat_load_upcase_table()
with exfat_calc_checksum32().
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
---
Changes in v2:
- rebase with patch 'optimize dir-cache' applied
Changes in v3:
- based on '[PATCH 2/4 v3] exfat: separate the boot sector analysis'
fs/exfat/dir.c | 12 ++++++------
fs/exfat/exfat_fs.h | 5 ++---
fs/exfat/misc.c | 10 ++++------
fs/exfat/nls.c | 19 +++++++------------
4 files changed, 19 insertions(+), 27 deletions(-)
diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c
index 2902d285bf20..de43534aa299 100644
--- a/fs/exfat/dir.c
+++ b/fs/exfat/dir.c
@@ -491,7 +491,7 @@ int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
int ret = 0;
int i, num_entries;
sector_t sector;
- unsigned short chksum;
+ u16 chksum;
struct exfat_dentry *ep, *fep;
struct buffer_head *fbh, *bh;
@@ -500,7 +500,7 @@ int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
return -EIO;
num_entries = fep->dentry.file.num_ext + 1;
- chksum = exfat_calc_chksum_2byte(fep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
+ chksum = exfat_calc_chksum16(fep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
for (i = 1; i < num_entries; i++) {
ep = exfat_get_dentry(sb, p_dir, entry + i, &bh, NULL);
@@ -508,7 +508,7 @@ int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
ret = -EIO;
goto release_fbh;
}
- chksum = exfat_calc_chksum_2byte(ep, DENTRY_SIZE, chksum,
+ chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
CS_DEFAULT);
brelse(bh);
}
@@ -593,8 +593,8 @@ void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es)
for (i = 0; i < es->num_entries; i++) {
ep = exfat_get_dentry_cached(es, i);
- chksum = exfat_calc_chksum_2byte(ep, DENTRY_SIZE, chksum,
- chksum_type);
+ chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
+ chksum_type);
chksum_type = CS_DEFAULT;
}
ep = exfat_get_dentry_cached(es, 0);
@@ -1000,7 +1000,7 @@ int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei,
}
if (entry_type == TYPE_STREAM) {
- unsigned short name_hash;
+ u16 name_hash;
if (step != DIRENT_STEP_STRM) {
step = DIRENT_STEP_FILE;
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index eebbe5a84b2b..9188985694f0 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -137,7 +137,7 @@ struct exfat_dentry_namebuf {
struct exfat_uni_name {
/* +3 for null and for converting */
unsigned short name[MAX_NAME_LENGTH + 3];
- unsigned short name_hash;
+ u16 name_hash;
unsigned char name_len;
};
@@ -512,8 +512,7 @@ void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
void exfat_truncate_atime(struct timespec64 *ts);
void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
u8 *tz, __le16 *time, __le16 *date, u8 *time_cs);
-unsigned short exfat_calc_chksum_2byte(void *data, int len,
- unsigned short chksum, int type);
+u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type);
u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type);
void exfat_update_bh(struct super_block *sb, struct buffer_head *bh, int sync);
void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c
index b82d2dd5bd7c..17d41f3d3709 100644
--- a/fs/exfat/misc.c
+++ b/fs/exfat/misc.c
@@ -136,17 +136,15 @@ void exfat_truncate_atime(struct timespec64 *ts)
ts->tv_nsec = 0;
}
-unsigned short exfat_calc_chksum_2byte(void *data, int len,
- unsigned short chksum, int type)
+u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type)
{
int i;
- unsigned char *c = (unsigned char *)data;
+ u8 *c = (u8 *)data;
for (i = 0; i < len; i++, c++) {
- if (((i == 2) || (i == 3)) && (type == CS_DIR_ENTRY))
+ if (unlikely(type == CS_DIR_ENTRY && (i == 2 || i == 3)))
continue;
- chksum = (((chksum & 1) << 15) | ((chksum & 0xFFFE) >> 1)) +
- (unsigned short)*c;
+ chksum = ((chksum << 15) | (chksum >> 1)) + *c;
}
return chksum;
}
diff --git a/fs/exfat/nls.c b/fs/exfat/nls.c
index 1ebda90cbdd7..19321773dd07 100644
--- a/fs/exfat/nls.c
+++ b/fs/exfat/nls.c
@@ -527,7 +527,7 @@ static int exfat_utf8_to_utf16(struct super_block *sb,
*uniname = '\0';
p_uniname->name_len = unilen;
- p_uniname->name_hash = exfat_calc_chksum_2byte(upname, unilen << 1, 0,
+ p_uniname->name_hash = exfat_calc_chksum16(upname, unilen << 1, 0,
CS_DEFAULT);
if (p_lossy)
@@ -623,7 +623,7 @@ static int exfat_nls_to_ucs2(struct super_block *sb,
*uniname = '\0';
p_uniname->name_len = unilen;
- p_uniname->name_hash = exfat_calc_chksum_2byte(upname, unilen << 1, 0,
+ p_uniname->name_hash = exfat_calc_chksum16(upname, unilen << 1, 0,
CS_DEFAULT);
if (p_lossy)
@@ -655,7 +655,8 @@ static int exfat_load_upcase_table(struct super_block *sb,
{
struct exfat_sb_info *sbi = EXFAT_SB(sb);
unsigned int sect_size = sb->s_blocksize;
- unsigned int i, index = 0, checksum = 0;
+ unsigned int i, index = 0;
+ u32 chksum = 0;
int ret;
unsigned char skip = false;
unsigned short *upcase_table;
@@ -681,13 +682,6 @@ static int exfat_load_upcase_table(struct super_block *sb,
for (i = 0; i < sect_size && index <= 0xFFFF; i += 2) {
unsigned short uni = get_unaligned_le16(bh->b_data + i);
- checksum = ((checksum & 1) ? 0x80000000 : 0) +
- (checksum >> 1) +
- *(((unsigned char *)bh->b_data) + i);
- checksum = ((checksum & 1) ? 0x80000000 : 0) +
- (checksum >> 1) +
- *(((unsigned char *)bh->b_data) + (i + 1));
-
if (skip) {
index += uni;
skip = false;
@@ -701,13 +695,14 @@ static int exfat_load_upcase_table(struct super_block *sb,
}
}
brelse(bh);
+ chksum = exfat_calc_chksum32(bh->b_data, i, chksum, CS_DEFAULT);
}
- if (index >= 0xFFFF && utbl_checksum == checksum)
+ if (index >= 0xFFFF && utbl_checksum == chksum)
return 0;
exfat_err(sb, "failed to load upcase table (idx : 0x%08x, chksum : 0x%08x, utbl_chksum : 0x%08x)",
- index, checksum, utbl_checksum);
+ index, chksum, utbl_checksum);
ret = -EINVAL;
free_table:
exfat_free_upcase_table(sbi);
--
2.25.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* RE: [PATCH 4/4 v3] exfat: standardize checksum calculation
2020-05-29 10:14 ` [PATCH 4/4 v3] exfat: standardize checksum calculation Tetsuhiro Kohada
@ 2020-06-01 12:20 ` Sungjong Seo
0 siblings, 0 replies; 7+ messages in thread
From: Sungjong Seo @ 2020-06-01 12:20 UTC (permalink / raw)
To: 'Tetsuhiro Kohada'
Cc: kohada.tetsuhiro, mori.takahiro, motai.hirotaka,
'Namjae Jeon', linux-fsdevel, linux-kernel
> To clarify that it is a 16-bit checksum, the parts related to the 16-bit
> checksum are renamed and change type to u16.
> Furthermore, replace checksum calculation in exfat_load_upcase_table()
> with exfat_calc_checksum32().
>
> Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
> ---
> Changes in v2:
> - rebase with patch 'optimize dir-cache' applied Changes in v3:
> - based on '[PATCH 2/4 v3] exfat: separate the boot sector analysis'
>
> fs/exfat/dir.c | 12 ++++++------
> fs/exfat/exfat_fs.h | 5 ++---
> fs/exfat/misc.c | 10 ++++------
> fs/exfat/nls.c | 19 +++++++------------
> 4 files changed, 19 insertions(+), 27 deletions(-)
>
> diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index
> 2902d285bf20..de43534aa299 100644
> --- a/fs/exfat/dir.c
> +++ b/fs/exfat/dir.c
> @@ -491,7 +491,7 @@ int exfat_update_dir_chksum(struct inode *inode,
> struct exfat_chain *p_dir,
> int ret = 0;
> int i, num_entries;
> sector_t sector;
> - unsigned short chksum;
> + u16 chksum;
> struct exfat_dentry *ep, *fep;
> struct buffer_head *fbh, *bh;
>
> @@ -500,7 +500,7 @@ int exfat_update_dir_chksum(struct inode *inode,
> struct exfat_chain *p_dir,
> return -EIO;
>
> num_entries = fep->dentry.file.num_ext + 1;
> - chksum = exfat_calc_chksum_2byte(fep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
> + chksum = exfat_calc_chksum16(fep, DENTRY_SIZE, 0, CS_DIR_ENTRY);
>
> for (i = 1; i < num_entries; i++) {
> ep = exfat_get_dentry(sb, p_dir, entry + i, &bh, NULL); @@ -
> 508,7 +508,7 @@ int exfat_update_dir_chksum(struct inode *inode, struct
> exfat_chain *p_dir,
> ret = -EIO;
> goto release_fbh;
> }
> - chksum = exfat_calc_chksum_2byte(ep, DENTRY_SIZE, chksum,
> + chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
> CS_DEFAULT);
> brelse(bh);
> }
> @@ -593,8 +593,8 @@ void exfat_update_dir_chksum_with_entry_set(struct
> exfat_entry_set_cache *es)
>
> for (i = 0; i < es->num_entries; i++) {
> ep = exfat_get_dentry_cached(es, i);
> - chksum = exfat_calc_chksum_2byte(ep, DENTRY_SIZE, chksum,
> - chksum_type);
> + chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum,
> + chksum_type);
> chksum_type = CS_DEFAULT;
> }
> ep = exfat_get_dentry_cached(es, 0);
> @@ -1000,7 +1000,7 @@ int exfat_find_dir_entry(struct super_block *sb,
> struct exfat_inode_info *ei,
> }
>
> if (entry_type == TYPE_STREAM) {
> - unsigned short name_hash;
> + u16 name_hash;
>
> if (step != DIRENT_STEP_STRM) {
> step = DIRENT_STEP_FILE;
> diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h index
> eebbe5a84b2b..9188985694f0 100644
> --- a/fs/exfat/exfat_fs.h
> +++ b/fs/exfat/exfat_fs.h
> @@ -137,7 +137,7 @@ struct exfat_dentry_namebuf { struct exfat_uni_name {
> /* +3 for null and for converting */
> unsigned short name[MAX_NAME_LENGTH + 3];
> - unsigned short name_hash;
> + u16 name_hash;
> unsigned char name_len;
> };
>
> @@ -512,8 +512,7 @@ void exfat_get_entry_time(struct exfat_sb_info *sbi,
> struct timespec64 *ts, void exfat_truncate_atime(struct timespec64 *ts);
> void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64
*ts,
> u8 *tz, __le16 *time, __le16 *date, u8 *time_cs); -unsigned
> short exfat_calc_chksum_2byte(void *data, int len,
> - unsigned short chksum, int type);
> +u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type);
> u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type); void
> exfat_update_bh(struct super_block *sb, struct buffer_head *bh, int sync);
> void exfat_chain_set(struct exfat_chain *ec, unsigned int dir, diff --git
> a/fs/exfat/misc.c b/fs/exfat/misc.c index b82d2dd5bd7c..17d41f3d3709
> 100644
> --- a/fs/exfat/misc.c
> +++ b/fs/exfat/misc.c
> @@ -136,17 +136,15 @@ void exfat_truncate_atime(struct timespec64 *ts)
> ts->tv_nsec = 0;
> }
>
> -unsigned short exfat_calc_chksum_2byte(void *data, int len,
> - unsigned short chksum, int type)
> +u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type)
> {
> int i;
> - unsigned char *c = (unsigned char *)data;
> + u8 *c = (u8 *)data;
>
> for (i = 0; i < len; i++, c++) {
> - if (((i == 2) || (i == 3)) && (type == CS_DIR_ENTRY))
> + if (unlikely(type == CS_DIR_ENTRY && (i == 2 || i == 3)))
> continue;
> - chksum = (((chksum & 1) << 15) | ((chksum & 0xFFFE) >> 1)) +
> - (unsigned short)*c;
> + chksum = ((chksum << 15) | (chksum >> 1)) + *c;
> }
> return chksum;
> }
> diff --git a/fs/exfat/nls.c b/fs/exfat/nls.c index
> 1ebda90cbdd7..19321773dd07 100644
> --- a/fs/exfat/nls.c
> +++ b/fs/exfat/nls.c
> @@ -527,7 +527,7 @@ static int exfat_utf8_to_utf16(struct super_block *sb,
>
> *uniname = '\0';
> p_uniname->name_len = unilen;
> - p_uniname->name_hash = exfat_calc_chksum_2byte(upname, unilen << 1,
> 0,
> + p_uniname->name_hash = exfat_calc_chksum16(upname, unilen << 1, 0,
> CS_DEFAULT);
>
> if (p_lossy)
> @@ -623,7 +623,7 @@ static int exfat_nls_to_ucs2(struct super_block *sb,
>
> *uniname = '\0';
> p_uniname->name_len = unilen;
> - p_uniname->name_hash = exfat_calc_chksum_2byte(upname, unilen << 1,
> 0,
> + p_uniname->name_hash = exfat_calc_chksum16(upname, unilen << 1, 0,
> CS_DEFAULT);
>
> if (p_lossy)
> @@ -655,7 +655,8 @@ static int exfat_load_upcase_table(struct super_block
> *sb, {
> struct exfat_sb_info *sbi = EXFAT_SB(sb);
> unsigned int sect_size = sb->s_blocksize;
> - unsigned int i, index = 0, checksum = 0;
> + unsigned int i, index = 0;
> + u32 chksum = 0;
> int ret;
> unsigned char skip = false;
> unsigned short *upcase_table;
> @@ -681,13 +682,6 @@ static int exfat_load_upcase_table(struct super_block
> *sb,
> for (i = 0; i < sect_size && index <= 0xFFFF; i += 2) {
> unsigned short uni = get_unaligned_le16(bh->b_data +
> i);
>
> - checksum = ((checksum & 1) ? 0x80000000 : 0) +
> - (checksum >> 1) +
> - *(((unsigned char *)bh->b_data) + i);
> - checksum = ((checksum & 1) ? 0x80000000 : 0) +
> - (checksum >> 1) +
> - *(((unsigned char *)bh->b_data) + (i + 1));
> -
> if (skip) {
> index += uni;
> skip = false;
> @@ -701,13 +695,14 @@ static int exfat_load_upcase_table(struct
> super_block *sb,
> }
> }
> brelse(bh);
> + chksum = exfat_calc_chksum32(bh->b_data, i, chksum,
> CS_DEFAULT);
> }
>
> - if (index >= 0xFFFF && utbl_checksum == checksum)
> + if (index >= 0xFFFF && utbl_checksum == chksum)
> return 0;
>
> exfat_err(sb, "failed to load upcase table (idx : 0x%08x, chksum :
> 0x%08x, utbl_chksum : 0x%08x)",
> - index, checksum, utbl_checksum);
> + index, chksum, utbl_checksum);
> ret = -EINVAL;
> free_table:
> exfat_free_upcase_table(sbi);
> --
> 2.25.1
^ permalink raw reply [flat|nested] 7+ messages in thread
* RE: [PATCH 1/4 v3] exfat: redefine PBR as boot_sector
2020-05-29 10:14 ` [PATCH 1/4 v3] exfat: redefine PBR as boot_sector Tetsuhiro Kohada
` (2 preceding siblings ...)
2020-05-29 10:14 ` [PATCH 4/4 v3] exfat: standardize checksum calculation Tetsuhiro Kohada
@ 2020-06-01 12:18 ` Sungjong Seo
3 siblings, 0 replies; 7+ messages in thread
From: Sungjong Seo @ 2020-06-01 12:18 UTC (permalink / raw)
To: 'Tetsuhiro Kohada'
Cc: kohada.tetsuhiro, mori.takahiro, motai.hirotaka,
'Namjae Jeon', linux-fsdevel, linux-kernel
> Aggregate PBR related definitions and redefine as "boot_sector" to comply
> with the exFAT specification.
> And, rename variable names including 'pbr'.
>
> Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
> ---
> Changes in v2:
> - rebase with patch 'optimize dir-cache' applied Changes in v3:
> - rename BOOTSEC_OEM_NAME_LEN to BOOTSEC_FS_NAME_LEN
> - rename oem_name to fs_name in struct boot_sector
>
> fs/exfat/exfat_fs.h | 2 +-
> fs/exfat/exfat_raw.h | 79 +++++++++++++++--------------------------
> fs/exfat/super.c | 84 ++++++++++++++++++++++----------------------
> 3 files changed, 72 insertions(+), 93 deletions(-)
>
> diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h index
> 5caad1380818..9673e2d31045 100644
> --- a/fs/exfat/exfat_fs.h
> +++ b/fs/exfat/exfat_fs.h
> @@ -227,7 +227,7 @@ struct exfat_sb_info {
> unsigned int root_dir; /* root dir cluster */
> unsigned int dentries_per_clu; /* num of dentries per cluster */
> unsigned int vol_flag; /* volume dirty flag */
> - struct buffer_head *pbr_bh; /* buffer_head of PBR sector */
> + struct buffer_head *boot_bh; /* buffer_head of BOOT sector */
>
> unsigned int map_clu; /* allocation bitmap start cluster */
> unsigned int map_sectors; /* num of allocation bitmap sectors */
> diff --git a/fs/exfat/exfat_raw.h b/fs/exfat/exfat_raw.h index
> 8d6c64a7546d..07f74190df44 100644
> --- a/fs/exfat/exfat_raw.h
> +++ b/fs/exfat/exfat_raw.h
> @@ -8,7 +8,8 @@
>
> #include <linux/types.h>
>
> -#define PBR_SIGNATURE 0xAA55
> +#define BOOT_SIGNATURE 0xAA55
> +#define EXBOOT_SIGNATURE 0xAA550000
>
> #define EXFAT_MAX_FILE_LEN 255
>
> @@ -55,7 +56,7 @@
>
> /* checksum types */
> #define CS_DIR_ENTRY 0
> -#define CS_PBR_SECTOR 1
> +#define CS_BOOT_SECTOR 1
> #define CS_DEFAULT 2
>
> /* file attributes */
> @@ -69,57 +70,35 @@
> #define ATTR_RWMASK (ATTR_HIDDEN | ATTR_SYSTEM | ATTR_VOLUME
> | \
> ATTR_SUBDIR | ATTR_ARCHIVE)
>
> -#define PBR64_JUMP_BOOT_LEN 3
> -#define PBR64_OEM_NAME_LEN 8
> -#define PBR64_RESERVED_LEN 53
> +#define BOOTSEC_JUMP_BOOT_LEN 3
> +#define BOOTSEC_FS_NAME_LEN 8
> +#define BOOTSEC_OLDBPB_LEN 53
>
> #define EXFAT_FILE_NAME_LEN 15
>
> -/* EXFAT BIOS parameter block (64 bytes) */ -struct bpb64 {
> - __u8 jmp_boot[PBR64_JUMP_BOOT_LEN];
> - __u8 oem_name[PBR64_OEM_NAME_LEN];
> - __u8 res_zero[PBR64_RESERVED_LEN];
> -} __packed;
> -
> -/* EXFAT EXTEND BIOS parameter block (56 bytes) */ -struct bsx64 {
> - __le64 vol_offset;
> - __le64 vol_length;
> - __le32 fat_offset;
> - __le32 fat_length;
> - __le32 clu_offset;
> - __le32 clu_count;
> - __le32 root_cluster;
> - __le32 vol_serial;
> - __u8 fs_version[2];
> - __le16 vol_flags;
> - __u8 sect_size_bits;
> - __u8 sect_per_clus_bits;
> - __u8 num_fats;
> - __u8 phy_drv_no;
> - __u8 perc_in_use;
> - __u8 reserved2[7];
> -} __packed;
> -
> -/* EXFAT PBR[BPB+BSX] (120 bytes) */
> -struct pbr64 {
> - struct bpb64 bpb;
> - struct bsx64 bsx;
> -} __packed;
> -
> -/* Common PBR[Partition Boot Record] (512 bytes) */ -struct pbr {
> - union {
> - __u8 raw[64];
> - struct bpb64 f64;
> - } bpb;
> - union {
> - __u8 raw[56];
> - struct bsx64 f64;
> - } bsx;
> - __u8 boot_code[390];
> - __le16 signature;
> +/* EXFAT: Main and Backup Boot Sector (512 bytes) */ struct boot_sector
> +{
> + __u8 jmp_boot[BOOTSEC_JUMP_BOOT_LEN];
> + __u8 fs_name[BOOTSEC_FS_NAME_LEN];
> + __u8 must_be_zero[BOOTSEC_OLDBPB_LEN];
> + __le64 partition_offset;
> + __le64 vol_length;
> + __le32 fat_offset;
> + __le32 fat_length;
> + __le32 clu_offset;
> + __le32 clu_count;
> + __le32 root_cluster;
> + __le32 vol_serial;
> + __u8 fs_revision[2];
> + __le16 vol_flags;
> + __u8 sect_size_bits;
> + __u8 sect_per_clus_bits;
> + __u8 num_fats;
> + __u8 drv_sel;
> + __u8 percent_in_use;
> + __u8 reserved[7];
> + __u8 boot_code[390];
> + __le16 signature;
> } __packed;
>
> struct exfat_dentry {
> diff --git a/fs/exfat/super.c b/fs/exfat/super.c index
> c1f47f4071a8..e60d28e73ff0 100644
> --- a/fs/exfat/super.c
> +++ b/fs/exfat/super.c
> @@ -49,7 +49,7 @@ static void exfat_put_super(struct super_block *sb)
> sync_blockdev(sb->s_bdev);
> exfat_set_vol_flags(sb, VOL_CLEAN);
> exfat_free_bitmap(sbi);
> - brelse(sbi->pbr_bh);
> + brelse(sbi->boot_bh);
> mutex_unlock(&sbi->s_lock);
>
> call_rcu(&sbi->rcu, exfat_delayed_free); @@ -101,7 +101,7 @@ static
> int exfat_statfs(struct dentry *dentry, struct kstatfs *buf) int
> exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag) {
> struct exfat_sb_info *sbi = EXFAT_SB(sb);
> - struct pbr64 *bpb = (struct pbr64 *)sbi->pbr_bh->b_data;
> + struct boot_sector *p_boot = (struct boot_sector
> +*)sbi->boot_bh->b_data;
> bool sync;
>
> /* flags are not changed */
> @@ -116,18 +116,18 @@ int exfat_set_vol_flags(struct super_block *sb,
> unsigned short new_flag)
> if (sb_rdonly(sb))
> return 0;
>
> - bpb->bsx.vol_flags = cpu_to_le16(new_flag);
> + p_boot->vol_flags = cpu_to_le16(new_flag);
>
> - if (new_flag == VOL_DIRTY && !buffer_dirty(sbi->pbr_bh))
> + if (new_flag == VOL_DIRTY && !buffer_dirty(sbi->boot_bh))
> sync = true;
> else
> sync = false;
>
> - set_buffer_uptodate(sbi->pbr_bh);
> - mark_buffer_dirty(sbi->pbr_bh);
> + set_buffer_uptodate(sbi->boot_bh);
> + mark_buffer_dirty(sbi->boot_bh);
>
> if (sync)
> - sync_dirty_buffer(sbi->pbr_bh);
> + sync_dirty_buffer(sbi->boot_bh);
> return 0;
> }
>
> @@ -366,13 +366,14 @@ static int exfat_read_root(struct inode *inode)
> return 0;
> }
>
> -static struct pbr *exfat_read_pbr_with_logical_sector(struct super_block
> *sb)
> +static struct boot_sector *exfat_read_boot_with_logical_sector(
> + struct super_block *sb)
> {
> struct exfat_sb_info *sbi = EXFAT_SB(sb);
> - struct pbr *p_pbr = (struct pbr *) (sbi->pbr_bh)->b_data;
> + struct boot_sector *p_boot = (struct boot_sector
> +*)sbi->boot_bh->b_data;
> unsigned short logical_sect = 0;
>
> - logical_sect = 1 << p_pbr->bsx.f64.sect_size_bits;
> + logical_sect = 1 << p_boot->sect_size_bits;
>
> if (!is_power_of_2(logical_sect) ||
> logical_sect < 512 || logical_sect > 4096) { @@ -387,49 +388,48
> @@ static struct pbr *exfat_read_pbr_with_logical_sector(struct
> super_block *sb)
> }
>
> if (logical_sect > sb->s_blocksize) {
> - brelse(sbi->pbr_bh);
> - sbi->pbr_bh = NULL;
> + brelse(sbi->boot_bh);
> + sbi->boot_bh = NULL;
>
> if (!sb_set_blocksize(sb, logical_sect)) {
> exfat_err(sb, "unable to set blocksize %u",
> logical_sect);
> return NULL;
> }
> - sbi->pbr_bh = sb_bread(sb, 0);
> - if (!sbi->pbr_bh) {
> + sbi->boot_bh = sb_bread(sb, 0);
> + if (!sbi->boot_bh) {
> exfat_err(sb, "unable to read boot sector (logical
> sector size = %lu)",
> sb->s_blocksize);
> return NULL;
> }
>
> - p_pbr = (struct pbr *)sbi->pbr_bh->b_data;
> + p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
> }
> - return p_pbr;
> + return p_boot;
> }
>
> /* mount the file system volume */
> static int __exfat_fill_super(struct super_block *sb) {
> int ret;
> - struct pbr *p_pbr;
> - struct pbr64 *p_bpb;
> + struct boot_sector *p_boot;
> struct exfat_sb_info *sbi = EXFAT_SB(sb);
>
> /* set block size to read super block */
> sb_min_blocksize(sb, 512);
>
> /* read boot sector */
> - sbi->pbr_bh = sb_bread(sb, 0);
> - if (!sbi->pbr_bh) {
> + sbi->boot_bh = sb_bread(sb, 0);
> + if (!sbi->boot_bh) {
> exfat_err(sb, "unable to read boot sector");
> return -EIO;
> }
>
> /* PRB is read */
> - p_pbr = (struct pbr *)sbi->pbr_bh->b_data;
> + p_boot = (struct boot_sector *)sbi->boot_bh->b_data;
>
> - /* check the validity of PBR */
> - if (le16_to_cpu((p_pbr->signature)) != PBR_SIGNATURE) {
> + /* check the validity of BOOT */
> + if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) {
> exfat_err(sb, "invalid boot record signature");
> ret = -EINVAL;
> goto free_bh;
> @@ -437,8 +437,8 @@ static int __exfat_fill_super(struct super_block *sb)
>
>
> /* check logical sector size */
> - p_pbr = exfat_read_pbr_with_logical_sector(sb);
> - if (!p_pbr) {
> + p_boot = exfat_read_boot_with_logical_sector(sb);
> + if (!p_boot) {
> ret = -EIO;
> goto free_bh;
> }
> @@ -447,43 +447,43 @@ static int __exfat_fill_super(struct super_block
*sb)
> * res_zero field must be filled with zero to prevent mounting
> * from FAT volume.
> */
> - if (memchr_inv(p_pbr->bpb.f64.res_zero, 0,
> - sizeof(p_pbr->bpb.f64.res_zero))) {
> + if (memchr_inv(p_boot->must_be_zero, 0,
> + sizeof(p_boot->must_be_zero))) {
> ret = -EINVAL;
> goto free_bh;
> }
>
> - p_bpb = (struct pbr64 *)p_pbr;
> - if (!p_bpb->bsx.num_fats) {
> + p_boot = (struct boot_sector *)p_boot;
> + if (!p_boot->num_fats) {
> exfat_err(sb, "bogus number of FAT structure");
> ret = -EINVAL;
> goto free_bh;
> }
>
> - sbi->sect_per_clus = 1 << p_bpb->bsx.sect_per_clus_bits;
> - sbi->sect_per_clus_bits = p_bpb->bsx.sect_per_clus_bits;
> + sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits;
> + sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits;
> sbi->cluster_size_bits = sbi->sect_per_clus_bits + sb-
> >s_blocksize_bits;
> sbi->cluster_size = 1 << sbi->cluster_size_bits;
> - sbi->num_FAT_sectors = le32_to_cpu(p_bpb->bsx.fat_length);
> - sbi->FAT1_start_sector = le32_to_cpu(p_bpb->bsx.fat_offset);
> - sbi->FAT2_start_sector = p_bpb->bsx.num_fats == 1 ?
> + sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length);
> + sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset);
> + sbi->FAT2_start_sector = p_boot->num_fats == 1 ?
> sbi->FAT1_start_sector :
> sbi->FAT1_start_sector + sbi->num_FAT_sectors;
> - sbi->data_start_sector = le32_to_cpu(p_bpb->bsx.clu_offset);
> - sbi->num_sectors = le64_to_cpu(p_bpb->bsx.vol_length);
> + sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset);
> + sbi->num_sectors = le64_to_cpu(p_boot->vol_length);
> /* because the cluster index starts with 2 */
> - sbi->num_clusters = le32_to_cpu(p_bpb->bsx.clu_count) +
> + sbi->num_clusters = le32_to_cpu(p_boot->clu_count) +
> EXFAT_RESERVED_CLUSTERS;
>
> - sbi->root_dir = le32_to_cpu(p_bpb->bsx.root_cluster);
> + sbi->root_dir = le32_to_cpu(p_boot->root_cluster);
> sbi->dentries_per_clu = 1 <<
> (sbi->cluster_size_bits - DENTRY_SIZE_BITS);
>
> - sbi->vol_flag = le16_to_cpu(p_bpb->bsx.vol_flags);
> + sbi->vol_flag = le16_to_cpu(p_boot->vol_flags);
> sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;
> sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED;
>
> - if (le16_to_cpu(p_bpb->bsx.vol_flags) & VOL_DIRTY) {
> + if (le16_to_cpu(p_boot->vol_flags) & VOL_DIRTY) {
> sbi->vol_flag |= VOL_DIRTY;
> exfat_warn(sb, "Volume was not properly unmounted. Some data
> may be corrupt. Please run fsck.");
> }
> @@ -517,7 +517,7 @@ static int __exfat_fill_super(struct super_block *sb)
> free_upcase_table:
> exfat_free_upcase_table(sbi);
> free_bh:
> - brelse(sbi->pbr_bh);
> + brelse(sbi->boot_bh);
> return ret;
> }
>
> @@ -608,7 +608,7 @@ static int exfat_fill_super(struct super_block *sb,
> struct fs_context *fc)
> free_table:
> exfat_free_upcase_table(sbi);
> exfat_free_bitmap(sbi);
> - brelse(sbi->pbr_bh);
> + brelse(sbi->boot_bh);
>
> check_nls_io:
> unload_nls(sbi->nls_io);
> --
> 2.25.1
^ permalink raw reply [flat|nested] 7+ messages in thread