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| author | Denys Vlasenko <vda.linux@googlemail.com> | 2010-08-31 01:50:03 +0200 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2010-08-31 01:50:03 +0200 |
| commit | 4e7dd3c363377aefd6ac60ab4335e773482bcca1 (patch) | |
| tree | 6b1245a04f63e2be22535da0c9d76a289b677453 | |
| parent | c71ec7061637ef490186144e03b8d9a61464d934 (diff) | |
| download | busybox-4e7dd3c363377aefd6ac60ab4335e773482bcca1.tar.gz | |
mkswap: clear 1st kilobyte. Closes bug 1831
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
| -rw-r--r-- | util-linux/mkswap.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/util-linux/mkswap.c b/util-linux/mkswap.c index 3f736faba..61a786e92 100644 --- a/util-linux/mkswap.c +++ b/util-linux/mkswap.c @@ -102,7 +102,15 @@ int mkswap_main(int argc UNUSED_PARAM, char **argv) printf("Setting up swapspace version 1, size = %"OFF_FMT"u bytes\n", len); mkswap_selinux_setcontext(fd, argv[0]); - /* Make a header. hdr is zero-filled so far... */ + /* hdr is zero-filled so far. Clear the first kbyte, or else + * mkswap-ing former FAT partition does NOT erase its signature. + * + * util-linux-ng 2.17.2 claims to erase it only if it does not see + * a partition table and is not run on whole disk. -f forces it. + */ + xwrite(fd, hdr, 1024); + + /* Fill the header. */ hdr->version = 1; hdr->last_page = (uoff_t)len / pagesize; @@ -123,7 +131,6 @@ int mkswap_main(int argc UNUSED_PARAM, char **argv) /* Write the header. Sync to disk because some kernel versions check * signature on disk (not in cache) during swapon. */ - xlseek(fd, 1024, SEEK_SET); xwrite(fd, hdr, NWORDS * 4); xlseek(fd, pagesize - 10, SEEK_SET); xwrite(fd, SWAPSPACE2, 10); |