busybox: fix missing install with suid bit set if FEATURE_SUID=y

With FEATURE_SUID=y one can install busybox binary belonging to root
with the suid bit set, enabling some applets to perform root-level
operations even when run by ordinary users. Busybox then drops
privileges for applets that don't need root access, before entering
their main() function.

Currently we don't install busybox binary with suid bit set, rendering
this feature unusable.

Note that we can't just "chmod u+s /bin/busybox" at runtime as a
"cheaper" solution: it would waste approximately 200KiB of FLASH (the
whole /bin/busybox binary gets copied into the overlay).

Ref: PR#2502
Signed-off-by: Henrique de Moraes Holschuh <henrique@nic.br>
[commit title/description facelift, use INSTALL_SUID variable]
Signed-off-by: Petr Štetiar <ynezz@true.cz>
This commit is contained in:
Henrique de Moraes Holschuh 2019-10-18 08:31:30 -03:00 committed by Petr Štetiar
parent 22b8a6263d
commit ad7c6102f2

View File

@ -113,6 +113,9 @@ endif
ifneq ($(CONFIG_BUSYBOX_$(BUSYBOX_SYM)_NTPD),)
$(INSTALL_BIN) ./files/sysntpd $(1)/etc/init.d/sysntpd
$(INSTALL_BIN) ./files/ntpd-hotplug $(1)/usr/sbin/ntpd-hotplug
endif
ifneq ($(CONFIG_BUSYBOX_$(BUSYBOX_SYM)_FEATURE_SUID),)
$(INSTALL_SUID) $(PKG_INSTALL_DIR)/bin/busybox $(1)/bin/busybox
endif
-rm -rf $(1)/lib64
endef