diff options
| author | Jan Schmidt <list.btrfs@jan-o-sch.net> | 2010-11-19 16:05:27 +0100 |
|---|---|---|
| committer | Chris Mason <chris.mason@oracle.com> | 2011-10-25 09:18:32 -0400 |
| commit | 42f9568bfdbec6a294320b955e28ccd9c7178a01 (patch) | |
| tree | 5f1b38a4f75485c1d0632e817f78f67fc8346243 /utils.c | |
| parent | c55248003ca39fa5d102c795474029bf1cfec999 (diff) | |
mkfs should initialize unused fields properly
we discovered speed setting is (probably unintentionally) initialized to 1 in make_btrfs(), while being initialized to 0 in btrfs_add_to_fsid(). initialization in make_btrfs() is due to reuse of buf after pwrite() without clearing it. consequently, code like
btrfs_set_extent_generation(buf, extent_item, 1);
writes to the same location in buf where speed will be placed, later. It may be a good idea to clear buf after each pwrite(), though leaving the struct btrfs_header intact.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Hugo Mills <hugo@carfax.org.uk>
Diffstat (limited to 'utils.c')
| -rw-r--r-- | utils.c | 10 |
1 files changed, 10 insertions, 0 deletions
@@ -212,6 +212,8 @@ int make_btrfs(int fd, const char *device, const char *label, BUG_ON(ret != leafsize); /* create the items for the extent tree */ + memset(buf->data+sizeof(struct btrfs_header), 0, + leafsize-sizeof(struct btrfs_header)); nritems = 0; itemoff = __BTRFS_LEAF_DATA_SIZE(leafsize); for (i = 1; i < 7; i++) { @@ -257,6 +259,8 @@ int make_btrfs(int fd, const char *device, const char *label, BUG_ON(ret != leafsize); /* create the chunk tree */ + memset(buf->data+sizeof(struct btrfs_header), 0, + leafsize-sizeof(struct btrfs_header)); nritems = 0; item_size = sizeof(*dev_item); itemoff = __BTRFS_LEAF_DATA_SIZE(leafsize) - item_size; @@ -338,6 +342,8 @@ int make_btrfs(int fd, const char *device, const char *label, ret = pwrite(fd, buf->data, leafsize, blocks[3]); /* create the device tree */ + memset(buf->data+sizeof(struct btrfs_header), 0, + leafsize-sizeof(struct btrfs_header)); nritems = 0; itemoff = __BTRFS_LEAF_DATA_SIZE(leafsize) - sizeof(struct btrfs_dev_extent); @@ -371,6 +377,8 @@ int make_btrfs(int fd, const char *device, const char *label, ret = pwrite(fd, buf->data, leafsize, blocks[4]); /* create the FS root */ + memset(buf->data+sizeof(struct btrfs_header), 0, + leafsize-sizeof(struct btrfs_header)); btrfs_set_header_bytenr(buf, blocks[5]); btrfs_set_header_owner(buf, BTRFS_FS_TREE_OBJECTID); btrfs_set_header_nritems(buf, 0); @@ -379,6 +387,8 @@ int make_btrfs(int fd, const char *device, const char *label, BUG_ON(ret != leafsize); /* finally create the csum root */ + memset(buf->data+sizeof(struct btrfs_header), 0, + leafsize-sizeof(struct btrfs_header)); btrfs_set_header_bytenr(buf, blocks[6]); btrfs_set_header_owner(buf, BTRFS_CSUM_TREE_OBJECTID); btrfs_set_header_nritems(buf, 0); |