linux-stable/include/linux/securebits.h
Andrew G. Morgan 086f7316f0 security: filesystem capabilities: fix fragile setuid fixup code
This commit includes a bugfix for the fragile setuid fixup code in the
case that filesystem capabilities are supported (in access()).  The effect
of this fix is gated on filesystem capability support because changing
securebits is only supported when filesystem capabilities support is
configured.)

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-04 10:40:08 -07:00

42 lines
1.8 KiB
C

#ifndef _LINUX_SECUREBITS_H
#define _LINUX_SECUREBITS_H 1
#define SECUREBITS_DEFAULT 0x00000000
/* When set UID 0 has no special privileges. When unset, we support
inheritance of root-permissions and suid-root executable under
compatibility mode. We raise the effective and inheritable bitmasks
*of the executable file* if the effective uid of the new process is
0. If the real uid is 0, we raise the effective (legacy) bit of the
executable file. */
#define SECURE_NOROOT 0
#define SECURE_NOROOT_LOCKED 1 /* make bit-0 immutable */
/* When set, setuid to/from uid 0 does not trigger capability-"fixup".
When unset, to provide compatiblility with old programs relying on
set*uid to gain/lose privilege, transitions to/from uid 0 cause
capabilities to be gained/lost. */
#define SECURE_NO_SETUID_FIXUP 2
#define SECURE_NO_SETUID_FIXUP_LOCKED 3 /* make bit-2 immutable */
/* When set, a process can retain its capabilities even after
transitioning to a non-root user (the set-uid fixup suppressed by
bit 2). Bit-4 is cleared when a process calls exec(); setting both
bit 4 and 5 will create a barrier through exec that no exec()'d
child can use this feature again. */
#define SECURE_KEEP_CAPS 4
#define SECURE_KEEP_CAPS_LOCKED 5 /* make bit-4 immutable */
/* Each securesetting is implemented using two bits. One bit specifies
whether the setting is on or off. The other bit specify whether the
setting is locked or not. A setting which is locked cannot be
changed from user-level. */
#define issecure_mask(X) (1 << (X))
#define issecure(X) (issecure_mask(X) & current->securebits)
#define SECURE_ALL_BITS (issecure_mask(SECURE_NOROOT) | \
issecure_mask(SECURE_NO_SETUID_FIXUP) | \
issecure_mask(SECURE_KEEP_CAPS))
#define SECURE_ALL_LOCKS (SECURE_ALL_BITS << 1)
#endif /* !_LINUX_SECUREBITS_H */