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Correct un-initialized fsid variable

master
Goffredo Baroncelli 2012-09-04 19:59:26 +02:00 committed by Chris Mason
parent bc130ecd02
commit 6eba900295
1 changed files with 16 additions and 4 deletions
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20
disk-io.c
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@ -910,6 +910,7 @@ struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr)
{
u8 fsid[BTRFS_FSID_SIZE];
int fsid_is_initialized = 0;
struct btrfs_super_block buf;
int i;
int ret;
@ -936,15 +937,26 @@ int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr)
if (ret < sizeof(buf))
break;
if (btrfs_super_bytenr(&buf) != bytenr ||
strncmp((char *)(&buf.magic), BTRFS_MAGIC,
if (btrfs_super_bytenr(&buf) != bytenr )
continue;
/* if magic is NULL, the device was removed */
if (buf.magic == 0 && i == 0)
return -1;
if (strncmp((char *)(&buf.magic), BTRFS_MAGIC,
sizeof(buf.magic)))
continue;
if (i == 0)
if (!fsid_is_initialized) {
memcpy(fsid, buf.fsid, sizeof(fsid));
else if (memcmp(fsid, buf.fsid, sizeof(fsid)))
fsid_is_initialized = 1;
} else if (memcmp(fsid, buf.fsid, sizeof(fsid))) {
/*
* the superblocks (the original one and
* its backups) contain data of different
* filesystems -> the super cannot be trusted
*/
continue;
}
if (btrfs_super_generation(&buf) > transid) {
memcpy(sb, &buf, sizeof(*sb));