File 0009-fsck-use-BytesPerSectorShift-of-boot-secto... of Package exfatprogs

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File 0009-fsck-use-BytesPerSectorShift-of-boot-sector-to-verif.patch of Package exfatprogs (Revision 17593a892749051976cac707aa62cf82)

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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

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File 0009-fsck-use-BytesPerSectorShift-of-boot-sector-to-verif.patch of Package exfatprogs (Revision 17593a892749051976cac707aa62cf82)

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