File 0009-fsck-use-BytesPerSectorShift-of-boot-sector-to-verif.patch of Package exfatprogs
From fbe842334690f04ae3a74dca25c78ea9f98ba4c4 Mon Sep 17 00:00:00 2001
From: Hyunchul Lee <hyc.lee@gmail.com>
Date: Wed, 12 May 2021 17:43:35 +0900
Subject: [PATCH 9/9] fsck: use BytesPerSectorShift of boot sector to verify
boot region
instead of the block device's sector size, use
BytesPerSectorShift of boot sector to read and
verify boot region.
Reported-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
(cherry picked from commit 478f39f0168992c7ca8e8bc9e99d10436bfc463b)
[ddiss: add EXFAT_MAX_SECTOR_SIZE definition from a13479b ("exfatprogs:
tune: use sector size extracted from the boot sector")]
Acked-by: David Disseldorp <ddiss@suse.de>
---
fsck/fsck.c | 146 ++++++++++++++++++++++++++++++---------------
include/libexfat.h | 2 +
2 files changed, 99 insertions(+), 49 deletions(-)
diff --git a/fsck/fsck.c b/fsck/fsck.c
index 747a771..00d1ca7 100644
--- a/fsck/fsck.c
+++ b/fsck/fsck.c
@@ -584,40 +584,39 @@ off_t exfat_c2o(struct exfat *exfat, unsigned int clus)
exfat->bs->bsx.sect_per_clus_bits));
}
-static int boot_region_checksum(struct exfat_blk_dev *bd, int bs_offset)
+static int boot_region_checksum(int dev_fd,
+ int bs_offset, unsigned int sect_size)
{
void *sect;
unsigned int i;
uint32_t checksum;
int ret = 0;
- unsigned int size;
- size = bd->sector_size;
- sect = malloc(size);
+ sect = malloc(sect_size);
if (!sect)
return -ENOMEM;
checksum = 0;
for (i = 0; i < 11; i++) {
- if (exfat_read(bd->dev_fd, sect, size,
- bs_offset * size + i * size) !=
- (ssize_t)size) {
+ if (exfat_read(dev_fd, sect, sect_size,
+ bs_offset * sect_size + i * sect_size) !=
+ (ssize_t)sect_size) {
exfat_err("failed to read boot region\n");
ret = -EIO;
goto out;
}
- boot_calc_checksum(sect, size, i == 0, &checksum);
+ boot_calc_checksum(sect, sect_size, i == 0, &checksum);
}
- if (exfat_read(bd->dev_fd, sect, size,
- bs_offset * size + 11 * size) !=
- (ssize_t)size) {
+ if (exfat_read(dev_fd, sect, sect_size,
+ bs_offset * sect_size + 11 * sect_size) !=
+ (ssize_t)sect_size) {
exfat_err("failed to read a boot checksum sector\n");
ret = -EIO;
goto out;
}
- for (i = 0; i < size/sizeof(checksum); i++) {
+ for (i = 0; i < sect_size/sizeof(checksum); i++) {
if (le32_to_cpu(((__le32 *)sect)[i]) != checksum) {
exfat_err("checksum of boot region is not correct. %#x, but expected %#x\n",
le32_to_cpu(((__le32 *)sect)[i]), checksum);
@@ -658,7 +657,8 @@ static int exfat_mark_volume_dirty(struct exfat *exfat, bool dirty)
}
static int read_boot_region(struct exfat_blk_dev *bd, struct pbr **pbr,
- int bs_offset)
+ int bs_offset, unsigned int sect_size,
+ bool verbose)
{
struct pbr *bs;
int ret = -EINVAL;
@@ -671,57 +671,66 @@ static int read_boot_region(struct exfat_blk_dev *bd, struct pbr **pbr,
}
if (exfat_read(bd->dev_fd, bs, sizeof(*bs),
- bs_offset * bd->sector_size) != (ssize_t)sizeof(*bs)) {
+ bs_offset * sect_size) != (ssize_t)sizeof(*bs)) {
exfat_err("failed to read a boot sector\n");
ret = -EIO;
goto err;
}
if (memcmp(bs->bpb.oem_name, "EXFAT ", 8) != 0) {
- exfat_err("failed to find exfat file system.\n");
+ if (verbose)
+ exfat_err("failed to find exfat file system\n");
goto err;
}
- ret = boot_region_checksum(bd, bs_offset);
+ ret = boot_region_checksum(bd->dev_fd, bs_offset, sect_size);
if (ret < 0)
goto err;
ret = -EINVAL;
if (EXFAT_SECTOR_SIZE(bs) < 512 || EXFAT_SECTOR_SIZE(bs) > 4 * KB) {
- exfat_err("too small or big sector size: %d\n",
- EXFAT_SECTOR_SIZE(bs));
+ if (verbose)
+ exfat_err("too small or big sector size: %d\n",
+ EXFAT_SECTOR_SIZE(bs));
goto err;
}
if (EXFAT_CLUSTER_SIZE(bs) > 32 * MB) {
- exfat_err("too big cluster size: %d\n", EXFAT_CLUSTER_SIZE(bs));
+ if (verbose)
+ exfat_err("too big cluster size: %d\n",
+ EXFAT_CLUSTER_SIZE(bs));
goto err;
}
if (bs->bsx.fs_version[1] != 1 || bs->bsx.fs_version[0] != 0) {
- exfat_err("unsupported exfat version: %d.%d\n",
- bs->bsx.fs_version[1], bs->bsx.fs_version[0]);
+ if (verbose)
+ exfat_err("unsupported exfat version: %d.%d\n",
+ bs->bsx.fs_version[1], bs->bsx.fs_version[0]);
goto err;
}
if (bs->bsx.num_fats != 1) {
- exfat_err("unsupported FAT count: %d\n", bs->bsx.num_fats);
+ if (verbose)
+ exfat_err("unsupported FAT count: %d\n",
+ bs->bsx.num_fats);
goto err;
}
if (le64_to_cpu(bs->bsx.vol_length) * EXFAT_SECTOR_SIZE(bs) >
bd->size) {
- exfat_err("too large sector count: %" PRIu64 ", expected: %llu\n",
- le64_to_cpu(bs->bsx.vol_length),
- bd->num_sectors);
+ if (verbose)
+ exfat_err("too large sector count: %" PRIu64 ", expected: %llu\n",
+ le64_to_cpu(bs->bsx.vol_length),
+ bd->num_sectors);
goto err;
}
if (le32_to_cpu(bs->bsx.clu_count) * EXFAT_CLUSTER_SIZE(bs) >
bd->size) {
- exfat_err("too large cluster count: %u, expected: %u\n",
- le32_to_cpu(bs->bsx.clu_count),
- bd->num_clusters);
+ if (verbose)
+ exfat_err("too large cluster count: %u, expected: %u\n",
+ le32_to_cpu(bs->bsx.clu_count),
+ bd->num_clusters);
goto err;
}
@@ -732,31 +741,31 @@ err:
return ret;
}
-static int restore_boot_region(struct exfat_blk_dev *bd)
+static int restore_boot_region(struct exfat_blk_dev *bd, unsigned int sect_size)
{
int i;
char *sector;
int ret;
- sector = malloc(bd->sector_size);
+ sector = malloc(sect_size);
if (!sector)
return -ENOMEM;
for (i = 0; i < 12; i++) {
- if (exfat_read(bd->dev_fd, sector, bd->sector_size,
- BACKUP_BOOT_SEC_IDX * bd->sector_size +
- i * bd->sector_size) !=
- (ssize_t)bd->sector_size) {
+ if (exfat_read(bd->dev_fd, sector, sect_size,
+ BACKUP_BOOT_SEC_IDX * sect_size +
+ i * sect_size) !=
+ (ssize_t)sect_size) {
ret = -EIO;
goto free_sector;
}
if (i == 0)
((struct pbr *)sector)->bsx.perc_in_use = 0xff;
- if (exfat_write(bd->dev_fd, sector, bd->sector_size,
- BOOT_SEC_IDX * bd->sector_size +
- i * bd->sector_size) !=
- (ssize_t)bd->sector_size) {
+ if (exfat_write(bd->dev_fd, sector, sect_size,
+ BOOT_SEC_IDX * sect_size +
+ i * sect_size) !=
+ (ssize_t)sect_size) {
ret = -EIO;
goto free_sector;
}
@@ -775,24 +784,63 @@ free_sector:
static int exfat_boot_region_check(struct exfat *exfat, struct pbr **bs)
{
+ struct pbr *boot_sect;
+ unsigned int sect_size;
int ret;
- ret = read_boot_region(exfat->blk_dev, bs, BOOT_SEC_IDX);
+ /* First, find out the exfat sector size */
+ boot_sect = malloc(sizeof(*boot_sect));
+ if (boot_sect == NULL)
+ return -ENOMEM;
+
+ if (exfat_read(exfat->blk_dev->dev_fd, boot_sect,
+ sizeof(*boot_sect), 0) != (ssize_t)sizeof(*boot_sect)) {
+ exfat_err("failed to read Main boot sector\n");
+ return -EIO;
+ }
+
+ sect_size = 1 << boot_sect->bsx.sect_size_bits;
+ free(boot_sect);
+
+ /* check boot regions */
+ ret = read_boot_region(exfat->blk_dev, bs,
+ BOOT_SEC_IDX, sect_size, true);
if (ret == -EINVAL && exfat_repair_ask(exfat, ER_BS_BOOT_REGION,
"boot region is corrupted. try to restore the region from backup"
)) {
- ret = read_boot_region(exfat->blk_dev, bs, BACKUP_BOOT_SEC_IDX);
- if (ret < 0) {
- exfat_err("backup boot region is also corrupted\n");
- return ret;
+ const unsigned int sector_sizes[] = {512, 4096, 1024, 2048};
+ unsigned int i;
+
+ if (sect_size >= 512 && sect_size <= EXFAT_MAX_SECTOR_SIZE) {
+ ret = read_boot_region(exfat->blk_dev, bs,
+ BACKUP_BOOT_SEC_IDX, sect_size,
+ false);
+ if (!ret)
+ goto restore;
}
- ret = restore_boot_region(exfat->blk_dev);
- if (ret < 0) {
- exfat_err("failed to restore boot region from backup\n");
- free(*bs);
- *bs = NULL;
- return ret;
+
+ for (i = 0; i < sizeof(sector_sizes)/sizeof(sector_sizes[0]); i++) {
+ if (sector_sizes[i] == sect_size)
+ continue;
+
+ ret = read_boot_region(exfat->blk_dev, bs,
+ BACKUP_BOOT_SEC_IDX,
+ sector_sizes[i], false);
+ if (!ret) {
+ sect_size = sector_sizes[i];
+ goto restore;
+ }
}
+ exfat_err("backup boot region is also corrupted\n");
+ }
+
+ return ret;
+restore:
+ ret = restore_boot_region(exfat->blk_dev, sect_size);
+ if (ret) {
+ exfat_err("failed to restore boot region from backup\n");
+ free(*bs);
+ *bs = NULL;
}
return ret;
}
diff --git a/include/libexfat.h b/include/libexfat.h
index 6a3ecb8..31244d7 100644
--- a/include/libexfat.h
+++ b/include/libexfat.h
@@ -37,6 +37,8 @@
/* Upcase tabel macro */
#define EXFAT_UPCASE_TABLE_SIZE (5836)
+#define EXFAT_MAX_SECTOR_SIZE 4096
+
enum {
BOOT_SEC_IDX = 0,
EXBOOT_SEC_IDX,
--
2.35.3
