[PATCH 61/74] libext2fs: fix ext2fs_open2() truncation of the superblock parameter

["Darrick J. Wong" <darrick.wong@oracle.com>]

Since it's possible for very large filesystems to store backup
superblocks at very large (> 2^32) block numbers, we need to be able
to handle the case of a caller directing us to read one of these
high-numbered backups.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 debugfs/debugfs.c   |    4 ++--
 e2fsck/journal.c    |    6 +++---
 e2fsck/unix.c       |    8 ++++----
 lib/ext2fs/ext2fs.h |    4 ++++
 lib/ext2fs/openfs.c |   23 ++++++++++++++++-------
 misc/dumpe2fs.c     |    4 ++--
 6 files changed, 31 insertions(+), 18 deletions(-)


diff --git a/debugfs/debugfs.c b/debugfs/debugfs.c
index e37d3f5..f9eb578 100644
--- a/debugfs/debugfs.c
+++ b/debugfs/debugfs.c
@@ -94,8 +94,8 @@ static void open_filesystem(char *device, int open_flags, blk64_t superblock,
 	if (catastrophic)
 		open_flags |= EXT2_FLAG_SKIP_MMP;
 
-	retval = ext2fs_open(device, open_flags, superblock, blocksize,
-			     unix_io_manager, &current_fs);
+	retval = ext2fs_open3(device, NULL, open_flags, superblock, blocksize,
+			      unix_io_manager, &current_fs);
 	if (retval) {
 		com_err(device, retval, "while opening filesystem");
 		current_fs = NULL;
diff --git a/e2fsck/journal.c b/e2fsck/journal.c
index 22f06e7..a7a714f 100644
--- a/e2fsck/journal.c
+++ b/e2fsck/journal.c
@@ -966,9 +966,9 @@ errcode_t e2fsck_run_ext3_journal(e2fsck_t ctx)
 
 	ext2fs_mmp_stop(ctx->fs);
 	ext2fs_free(ctx->fs);
-	retval = ext2fs_open(ctx->filesystem_name, EXT2_FLAG_RW,
-			     ctx->superblock, blocksize, io_ptr,
-			     &ctx->fs);
+	retval = ext2fs_open3(ctx->filesystem_name, NULL, EXT2_FLAG_RW,
+			      ctx->superblock, blocksize, io_ptr,
+			      &ctx->fs);
 	if (retval) {
 		com_err(ctx->program_name, retval,
 			_("while trying to re-open %s"),
diff --git a/e2fsck/unix.c b/e2fsck/unix.c
index 7a8fce2..261b84b 100644
--- a/e2fsck/unix.c
+++ b/e2fsck/unix.c
@@ -1042,7 +1042,7 @@ static errcode_t try_open_fs(e2fsck_t ctx, int flags, io_manager io_ptr,
 
 	*ret_fs = NULL;
 	if (ctx->superblock && ctx->blocksize) {
-		retval = ext2fs_open2(ctx->filesystem_name, ctx->io_options,
+		retval = ext2fs_open3(ctx->filesystem_name, ctx->io_options,
 				      flags, ctx->superblock, ctx->blocksize,
 				      io_ptr, ret_fs);
 	} else if (ctx->superblock) {
@@ -1053,7 +1053,7 @@ static errcode_t try_open_fs(e2fsck_t ctx, int flags, io_manager io_ptr,
 				ext2fs_free(*ret_fs);
 				*ret_fs = NULL;
 			}
-			retval = ext2fs_open2(ctx->filesystem_name,
+			retval = ext2fs_open3(ctx->filesystem_name,
 					      ctx->io_options, flags,
 					      ctx->superblock, blocksize,
 					      io_ptr, ret_fs);
@@ -1061,7 +1061,7 @@ static errcode_t try_open_fs(e2fsck_t ctx, int flags, io_manager io_ptr,
 				break;
 		}
 	} else
-		retval = ext2fs_open2(ctx->filesystem_name, ctx->io_options,
+		retval = ext2fs_open3(ctx->filesystem_name, ctx->io_options,
 				      flags, 0, 0, io_ptr, ret_fs);
 
 	if (retval == 0)
@@ -1377,7 +1377,7 @@ failure:
 	 * don't need to update the mount count and last checked
 	 * fields in the backup superblock (the kernel doesn't update
 	 * the backup superblocks anyway).  With newer versions of the
-	 * library this flag is set by ext2fs_open2(), but we set this
+	 * library this flag is set by ext2fs_open3(), but we set this
 	 * here just to be sure.  (No, we don't support e2fsck running
 	 * with some other libext2fs than the one that it was shipped
 	 * with, but just in case....)
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index d94fdd4..ba5c388 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -1480,6 +1480,10 @@ extern errcode_t ext2fs_open2(const char *name, const char *io_options,
 			      int flags, int superblock,
 			      unsigned int block_size, io_manager manager,
 			      ext2_filsys *ret_fs);
+extern errcode_t ext2fs_open3(const char *name, const char *io_options,
+			      int flags, blk64_t superblock,
+			      unsigned int block_size, io_manager manager,
+			      ext2_filsys *ret_fs);
 /*
  * The dgrp_t argument to these two functions is not actually a group number
  * but a block number offset within a group table!  Convert with the formula
diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
index 5cf6ae4..2639ae5 100644
--- a/lib/ext2fs/openfs.c
+++ b/lib/ext2fs/openfs.c
@@ -94,6 +94,15 @@ errcode_t ext2fs_open(const char *name, int flags, int superblock,
 			    manager, ret_fs);
 }
 
+errcode_t ext2fs_open2(const char *name, const char *io_options,
+		       int flags, int superblock,
+		       unsigned int block_size, io_manager manager,
+		       ext2_filsys *ret_fs)
+{
+	return ext2fs_open3(name, io_options, flags, superblock, block_size,
+			    manager, ret_fs);
+}
+
 /*
  *  Note: if superblock is non-zero, block-size must also be non-zero.
  * 	Superblock and block_size can be zero to use the default size.
@@ -108,8 +117,8 @@ errcode_t ext2fs_open(const char *name, int flags, int superblock,
  *	EXT2_FLAG_64BITS - Allow 64-bit bitfields (needed for large
  *				filesystems)
  */
-errcode_t ext2fs_open2(const char *name, const char *io_options,
-		       int flags, int superblock,
+errcode_t ext2fs_open3(const char *name, const char *io_options,
+		       int flags, blk64_t superblock,
 		       unsigned int block_size, io_manager manager,
 		       ext2_filsys *ret_fs)
 {
@@ -208,8 +217,8 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
 		if (retval)
 			goto cleanup;
 	}
-	retval = io_channel_read_blk(fs->io, superblock, -SUPERBLOCK_SIZE,
-				     fs->super);
+	retval = io_channel_read_blk64(fs->io, superblock, -SUPERBLOCK_SIZE,
+				       fs->super);
 	if (retval)
 		goto cleanup;
 	if (fs->orig_super)
@@ -410,9 +419,9 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
 	else
 		first_meta_bg = fs->desc_blocks;
 	if (first_meta_bg) {
-		retval = io_channel_read_blk(fs->io, group_block +
-					     group_zero_adjust + 1,
-					     first_meta_bg, dest);
+		retval = io_channel_read_blk64(fs->io, group_block +
+					       group_zero_adjust + 1,
+					       first_meta_bg, dest);
 		if (retval)
 			goto cleanup;
 #ifdef WORDS_BIGENDIAN
diff --git a/misc/dumpe2fs.c b/misc/dumpe2fs.c
index 3dbfcb9..0446f7f 100644
--- a/misc/dumpe2fs.c
+++ b/misc/dumpe2fs.c
@@ -621,7 +621,7 @@ int main (int argc, char ** argv)
 		for (use_blocksize = EXT2_MIN_BLOCK_SIZE;
 		     use_blocksize <= EXT2_MAX_BLOCK_SIZE;
 		     use_blocksize *= 2) {
-			retval = ext2fs_open (device_name, flags,
+			retval = ext2fs_open3(device_name, NULL, flags,
 					      use_superblock,
 					      use_blocksize, unix_io_manager,
 					      &fs);
@@ -629,7 +629,7 @@ int main (int argc, char ** argv)
 				break;
 		}
 	} else
-		retval = ext2fs_open (device_name, flags, use_superblock,
+		retval = ext2fs_open3(device_name, NULL, flags, use_superblock,
 				      use_blocksize, unix_io_manager, &fs);
 	if (retval) {
 		com_err (program_name, retval, _("while trying to open %s"),