From 24ed07818403f2ce52f9116a749036d58b91ca81 Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Thu, 24 Apr 2014 13:42:54 +0200 Subject: [PATCH] wipefs: don't erase nested partition tables by default It's possible the partition contains a partition table (BSD, or hybrid boot images). It could be unexpected for users that the lost all (or another) partitions when work with non-whole disk device. Let's require --force. For example: # wipefs --all /dev/sdb erases all including partition table, but on hybrid disk where the first partition starts at first sector (so partition table is within the first partition): # wipefs --all /dev/sdb1 /dev/sdb1: ignore nested "dos" partition table on non-whole disk device wipefs: Use the --force option to force erase. asks for --force. Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1077310 Signed-off-by: Karel Zak --- misc-utils/wipefs.8 | 5 +++++ misc-utils/wipefs.c | 14 +++++++++++++- 2 files changed, 18 insertions(+), 1 deletion(-) diff --git a/misc-utils/wipefs.8 b/misc-utils/wipefs.8 index 0f280b38a..207b67501 100644 --- a/misc-utils/wipefs.8 +++ b/misc-utils/wipefs.8 @@ -37,6 +37,11 @@ table will still be visible by another magic string on another offset. When used with option \fB-a\fR, all magic strings that are visible for libblkid are erased. +Note that by default +.B wipefs +does not erase nested partition tables on non-whole disk devices. The option +\-\-force is required. + .SH OPTIONS .TP .BR \-a , " \-\-all" diff --git a/misc-utils/wipefs.c b/misc-utils/wipefs.c index 5dfaf0c55..2c1ea5947 100644 --- a/misc-utils/wipefs.c +++ b/misc-utils/wipefs.c @@ -365,7 +365,7 @@ static void rereadpt(int fd, const char *devname) static struct wipe_desc * do_wipe(struct wipe_desc *wp, const char *devname, int flags) { - int mode = O_RDWR, reread = 0; + int mode = O_RDWR, reread = 0, need_force = 0; blkid_probe pr; struct wipe_desc *w, *wp0; int zap = (flags & WP_FL_ALL) ? 1 : wp->zap; @@ -405,6 +405,15 @@ do_wipe(struct wipe_desc *wp, const char *devname, int flags) if (!wp->on_disk) continue; + if (!(flags & WP_FL_FORCE) + && wp->is_parttable + && !blkid_probe_is_wholedisk(pr)) { + warnx(_("%s: ignore nested \"%s\" partition " + "table on non-whole disk device."), devname, wp->type); + need_force = 1; + continue; + } + if (zap) { if (backup) do_backup(wp, backup); @@ -419,6 +428,9 @@ do_wipe(struct wipe_desc *wp, const char *devname, int flags) warnx(_("%s: offset 0x%jx not found"), devname, w->offset); } + if (need_force) + warnx(_("Use the --force option to force erase.")); + fsync(blkid_probe_get_fd(pr)); if (reread && (mode & O_EXCL))