File 0002-fsck-repair-restore-boot-region-from-backup-boot-reg.patch of Package exfatprogs.31393
From 846d884a222d00f0eb563a49eb25f1906089b8b9 Mon Sep 17 00:00:00 2001
From: Hyunchul Lee <hyc.lee@gmail.com>
Date: Mon, 24 Aug 2020 15:24:21 +0900
Subject: [PATCH 2/9] fsck: repair: restore boot region from backup boot region
if the boot region is corrupted, restore it from
the backup boot region.
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
(cherry picked from commit 5a2896138e260265588c19167963eb8de96567cd)
Acked-by: David Disseldorp <ddiss@suse.de>
---
fsck/fsck.c | 150 +++++++++++++++++++++++++++++++-------------------
fsck/repair.c | 1 +
fsck/repair.h | 1 +
3 files changed, 95 insertions(+), 57 deletions(-)
diff --git a/fsck/fsck.c b/fsck/fsck.c
index 9732afb..981d6ab 100644
--- a/fsck/fsck.c
+++ b/fsck/fsck.c
@@ -204,20 +204,11 @@ static void free_exfat(struct exfat *exfat)
}
}
-static struct exfat *alloc_exfat(struct exfat_blk_dev *bd, struct pbr *bs)
+static int init_exfat(struct exfat *exfat, struct pbr *bs)
{
- struct exfat *exfat;
int i;
- exfat = (struct exfat *)calloc(1, sizeof(*exfat));
- if (!exfat) {
- free(bs);
- exfat_err("failed to allocate exfat\n");
- return NULL;
- }
-
INIT_LIST_HEAD(&exfat->dir_list);
- exfat->blk_dev = bd;
exfat->bs = bs;
exfat->clus_count = le32_to_cpu(bs->bsx.clu_count);
exfat->clus_size = EXFAT_CLUSTER_SIZE(bs);
@@ -250,10 +241,10 @@ static struct exfat *alloc_exfat(struct exfat_blk_dev *bd, struct pbr *bs)
if (!exfat->buffer_desc[i].dirty)
goto err;
}
- return exfat;
+ return 0;
err:
free_exfat(exfat);
- return NULL;
+ return -ENOMEM;
}
static void exfat_free_dir_list(struct exfat *exfat)
@@ -592,33 +583,33 @@ off_t exfat_c2o(struct exfat *exfat, unsigned int clus)
exfat->bs->bsx.sect_per_clus_bits));
}
-static int boot_region_checksum(struct exfat *exfat)
+static int boot_region_checksum(struct exfat_blk_dev *bd, int bs_offset)
{
void *sect;
unsigned int i;
uint32_t checksum;
int ret = 0;
- unsigned short size;
+ unsigned int size;
- size = EXFAT_SECTOR_SIZE(exfat->bs);
+ size = bd->sector_size;
sect = malloc(size);
if (!sect)
return -ENOMEM;
checksum = 0;
-
- boot_calc_checksum((unsigned char *)exfat->bs, size, true, &checksum);
- for (i = 1; i < 11; i++) {
- if (exfat_read(exfat->blk_dev->dev_fd, sect, size, i * size) !=
+ for (i = 0; i < 11; i++) {
+ if (exfat_read(bd->dev_fd, sect, size,
+ bs_offset * size + i * size) !=
(ssize_t)size) {
- exfat_err("failed to read boot regions\n");
+ exfat_err("failed to read boot region\n");
ret = -EIO;
goto out;
}
- boot_calc_checksum(sect, size, false, &checksum);
+ boot_calc_checksum(sect, size, i == 0, &checksum);
}
- if (exfat_read(exfat->blk_dev->dev_fd, sect, size, 11 * size) !=
+ if (exfat_read(bd->dev_fd, sect, size,
+ bs_offset * size + 11 * size) !=
(ssize_t)size) {
exfat_err("failed to read a boot checksum sector\n");
ret = -EIO;
@@ -627,33 +618,15 @@ static int boot_region_checksum(struct exfat *exfat)
for (i = 0; i < size/sizeof(checksum); i++) {
if (le32_to_cpu(((__le32 *)sect)[i]) != checksum) {
- if (exfat_repair_ask(exfat, ER_BS_CHECKSUM,
- "checksums of boot sector are not correct. "
- "%#x, but expected %#x",
- le32_to_cpu(((__le32 *)sect)[i]), checksum)) {
- goto out_write;
- } else {
- ret = -EINVAL;
- goto out;
- }
+ exfat_err("checksum of boot region is not correct. %#x, but expected %#x\n",
+ le32_to_cpu(((__le32 *)sect)[i]), checksum);
+ ret = -EINVAL;
+ goto out;
}
}
out:
free(sect);
return ret;
-
-out_write:
- for (i = 0; i < size/sizeof(checksum); i++)
- ((__le32 *)sect)[i] = cpu_to_le32(checksum);
-
- if (exfat_write(exfat->blk_dev->dev_fd,
- sect, size, size * 11) != size) {
- exfat_err("failed to write checksum sector\n");
- free(sect);
- return -EIO;
- }
- free(sect);
- return 0;
}
static int exfat_mark_volume_dirty(struct exfat *exfat, bool dirty)
@@ -683,18 +656,21 @@ static int exfat_mark_volume_dirty(struct exfat *exfat, bool dirty)
return 0;
}
-static int read_boot_region(struct exfat_blk_dev *bd, struct pbr **pbr)
+static int read_boot_region(struct exfat_blk_dev *bd, struct pbr **pbr,
+ int bs_offset)
{
struct pbr *bs;
+ int ret = -EINVAL;
+ *pbr = NULL;
bs = (struct pbr *)malloc(sizeof(struct pbr));
if (!bs) {
exfat_err("failed to allocate memory\n");
return -ENOMEM;
}
- if (exfat_read(bd->dev_fd, bs, sizeof(*bs), 0) !=
- (ssize_t)sizeof(*bs)) {
+ if (exfat_read(bd->dev_fd, bs, sizeof(*bs),
+ bs_offset * bd->sector_size) != (ssize_t)sizeof(*bs)) {
exfat_err("failed to read a boot sector\n");
free(bs);
return -EIO;
@@ -705,6 +681,10 @@ static int read_boot_region(struct exfat_blk_dev *bd, struct pbr **pbr)
goto err;
}
+ ret = boot_region_checksum(bd, bs_offset);
+ if (ret < 0)
+ goto err;
+
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));
@@ -747,7 +727,61 @@ static int read_boot_region(struct exfat_blk_dev *bd, struct pbr **pbr)
return 0;
err:
free(bs);
- return -EINVAL;
+ return ret;
+}
+
+static int restore_boot_region(struct exfat_blk_dev *bd)
+{
+ int i;
+ char *sector;
+
+ sector = malloc(bd->sector_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)
+ return -EIO;
+ 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)
+ return -EIO;
+ }
+ if (fsync(bd->dev_fd))
+ return -EIO;
+ free(sector);
+ return 0;
+}
+
+static int exfat_boot_region_check(struct exfat *exfat, struct pbr **bs)
+{
+ int ret;
+
+ ret = read_boot_region(exfat->blk_dev, bs, BOOT_SEC_IDX);
+ 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");
+ return ret;
+ }
+ ret = restore_boot_region(exfat->blk_dev);
+ if (ret < 0) {
+ exfat_err("failed to restore boot region from backup");
+ free(*bs);
+ *bs = NULL;
+ return ret;
+ }
+ }
+ return ret;
}
static void dentry_calc_checksum(struct exfat_dentry *dentry,
@@ -1485,26 +1519,28 @@ int main(int argc, char * const argv[])
return FSCK_EXIT_OPERATION_ERROR;
}
- ret = read_boot_region(&bd, &bs);
- if (ret)
- goto err;
-
- exfat = alloc_exfat(&bd, bs);
+ exfat = (struct exfat *)calloc(1, sizeof(*exfat));
if (!exfat) {
+ exfat_err("failed to allocate exfat\n");
ret = -ENOMEM;
goto err;
}
+ exfat->blk_dev = &bd;
exfat->options = ui.options;
- if (exfat_mark_volume_dirty(exfat, true)) {
- ret = -EIO;
+ ret = exfat_boot_region_check(exfat, &bs);
+ if (ret)
goto err;
- }
- ret = boot_region_checksum(exfat);
+ ret = init_exfat(exfat, bs);
if (ret)
goto err;
+ if (exfat_mark_volume_dirty(exfat, true)) {
+ ret = -EIO;
+ goto err;
+ }
+
exfat_debug("verifying root directory...\n");
ret = exfat_root_dir_check(exfat);
if (ret) {
diff --git a/fsck/repair.c b/fsck/repair.c
index fa6cdfb..c79d379 100644
--- a/fsck/repair.c
+++ b/fsck/repair.c
@@ -34,6 +34,7 @@ static const char *prompts[] = {
static struct exfat_repair_problem problems[] = {
{ER_BS_CHECKSUM, ERF_PREEN_YES, ERP_FIX},
+ {ER_BS_BOOT_REGION, 0, ERP_FIX},
{ER_DE_CHECKSUM, ERF_PREEN_YES, ERP_FIX},
{ER_FILE_VALID_SIZE, ERF_PREEN_YES, ERP_FIX},
{ER_FILE_INVALID_CLUS, ERF_DEFAULT_NO, ERP_TRUNCATE},
diff --git a/fsck/repair.h b/fsck/repair.h
index 6a34b9b..f7286b9 100644
--- a/fsck/repair.h
+++ b/fsck/repair.h
@@ -6,6 +6,7 @@
#define _REPAIR_H
#define ER_BS_CHECKSUM 0x00000001
+#define ER_BS_BOOT_REGION 0x00000002
#define ER_DE_CHECKSUM 0x00001001
#define ER_FILE_VALID_SIZE 0x00002001
#define ER_FILE_INVALID_CLUS 0x00002002
--
2.35.3
