Based on a patch from Steven McDonald <steven@steven-mcdonald.id.au>:
This makes 'unshare --user' work correctly in the case where the user's
shell is provided by busybox itself.
'unshare --user' creates a new user namespace without any uid mappings.
As a result, /bin/busybox is setuid nobody:nogroup within the
namespace, as that is the only user. However, since no uids are mapped,
attempting to call setgid/setuid fails, even though this would do
nothing:
$ unshare --user ./busybox.broken ash
ash: setgid: Invalid argument
'unshare --map-root-user' still works, but because Linux only allows
uid/gid mappings to be set up once, creating a root mapping makes such
a namespace useless for creating multi-user containers.
With this patch, setgid and setuid will not be called in the case where
they would do nothing, which is always the case inside a new user
namespace because all uids are effectively mapped to nobody:
$ id -u
1000
$ ls -lh busybox.fixed
-rwsr-xr-x 1 root root 826.2K May 21 00:33 busybox.fixed
$ unshare --user ./busybox.fixed ash
$ id -u
65534
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Before this change, BB_EXTRA_VERSION of "" resulted in:
"BusyBox v1.28.0.git () multi-call binary"
message, after the fix it is:
"BusyBox v1.28.0.git multi-call binary"
While at it, eliminate BB_BT and BANNER single-use macros.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
When this feature is enabled, blank passwords are not accepted by su
unless the user is on a secure TTY defined in /etc/securetty. This
resembles the default PAM configuration of some Linux distros which
specify the nullok_secure option for pam_unix.so.
Based on patch by Kaarle Ritvanen <kaarle.ritvanen@datakunkku.fi>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The "autolooped" mount (mount [-oloop] IMAGE /DIR/DIR)
always creates AUTOCLEARed loopdevs, so that umounting
drops them (and this does not require any code in the
umount userspace).
This happens since circa linux-2.6.25:
commit 96c5865559cee0f9cbc5173f3c949f6ce3525581
Date: Wed Feb 6 01:36:27 2008 -0800
Subject: Allow auto-destruction of loop devices
IOW: in this case, umount does not have to use -d
to drop the loopdev.
The explicit loop mount (mount /dev/loopN /DIR/DIR)
does not do this. In this case, umount without -d
should not drop loopdev.
Unfortunately, bbox umount currently always implies -d,
this probably needs fixing.
function old new delta
set_loop 537 597 +60
singlemount 1101 1138 +37
losetup_main 419 432 +13
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/0 up/down: 110/0) Total: 110 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
An example of such an error (should be compiled with DEBUG_SANITIZE):
runtime error: left shift of 1 by 31 places cannot be represented in
type 'int'
Signed-off-by: Rostislav Skudnov <rostislav@tuxera.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Good news that TLS_RSA_WITH_AES_256_CBC_SHA256 still works with new code ;)
This change adds inevitable extension to have different sized hashes and AES key sizes.
In libbb, md5_end() and shaX_end() are extended to return result size instead of void -
this helps *a lot* in tls (the cost is ~5 bytes per _end() function).
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Many other appletw don't - they unconditionally use get_terminal_wodth(),
and here the amount of code saved by FEATURE_AUTOWIDTH=n is tiny.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Redundant help texts (one which only repeats the description)
are deleted.
Descriptions and help texts are trimmed.
Some config options are moved, even across menus.
No config option _names_ are changed.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
libbb/appletlib.c:558:12: warning: 'ingroup' defined but
not used [-Wunused-function]
static int ingroup(uid_t u, gid_t g)
^~~~~~~
That function is used only if FEATURE_SUID_CONFIG is also enabled.
Signed-off-by: Cristian Ionescu-Idbohrn <cristian.ionescu-idbohrn@axis.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The selinux guys want you to get class values at runtime by converting
textual names into constants. Drop the deprecated headers and switch
to the new format.
This API has been around for years, so there shouldn't be an issue
with backwards compatibility.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
(1) restore entire sigaction, not only signal handler function
(2) do not use stdio when not sure WINCH did not interrupt a printf() or such.
function old new delta
cmdedit_setwidth - 81 +81
read_line_input 3682 3722 +40
lineedit_read_key 138 155 +17
put_prompt 55 51 -4
win_changed 93 47 -46
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/2 up/down: 138/-50) Total: 88 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
