linux/include
Justin Suess 6887c03bf2
landlock: Add LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS
Add a landlock_restrict_self(2) flag to set the no_new_privs attribute
of the calling thread only after enforcement of the ruleset:
no_new_privs is set if and only if the call succeeds.  This removes the
need for a prior prctl(2) PR_SET_NO_NEW_PRIVS call and guarantees that
a failed enforcement leaves the attribute unchanged.

Because no_new_privs is set by the call itself, the no_new_privs /
CAP_SYS_ADMIN requirement of landlock_restrict_self(2) is fulfilled by
construction, and the related EPERM check is skipped.

Unlike LANDLOCK_RESTRICT_SELF_LOG_SUBDOMAINS_OFF, this flag always
requires a valid ruleset: with a ruleset_fd of -1, such a call would be
nothing more than a Landlock-flavored prctl(2) PR_SET_NO_NEW_PRIVS, and
there is no valid use case for setting no_new_privs (possibly with
LANDLOCK_RESTRICT_SELF_TSYNC) without also enforcing Landlock
restrictions.  Rejecting these calls also keeps the option of giving
them a meaning later.

The attribute is only set past the last point of failure, just before
committing the new credentials.  When combined with
LANDLOCK_RESTRICT_SELF_TSYNC, no_new_privs is set on the sibling threads
as well, in their commit phase, with the same ordering.

Bump the Landlock ABI version to 11, and include the minimal related
test changes to keep the tests bisectable.

Cc: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Justin Suess <utilityemal77@gmail.com>
Link: https://patch.msgid.link/20260809212459.2427878-1-utilityemal77@gmail.com
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2026-08-15 09:14:46 +02:00
..
acpi ACPI: CPPC: Check all controls for fast switching 2026-07-22 15:09:14 +02:00
asm-generic mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
clocksource
crypto Networking changes for 7.2. 2026-06-17 08:17:00 +01:00
cxl
drm drm-misc-fixes for v7.2-rc5: 2026-07-24 18:30:29 +10:00
dt-bindings SoC fixes for 7.2 2026-07-17 08:52:09 -07:00
hyperv mshv: fix hv_input_get_system_property struct 2026-07-22 21:58:21 +00:00
keys keys: Pin request_key_auth payload in instantiate paths 2026-06-15 15:19:13 +03:00
kunit linux_kselftest-kunit-7.2-rc1 2026-06-16 16:33:57 +05:30
kvm KVM: arm64: vgic: Fix race between LPI release and re-registration 2026-07-23 09:56:57 +01:00
linux vfs-7.2-rc6.fixes 2026-08-02 10:12:21 -07:00
math-emu
media
memory
misc
net Bluetooth: ISO: fix race of kfree vs kref_get_unless_zero 2026-07-28 16:13:12 -04:00
pcmcia Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (headers) 2026-07-03 07:38:16 +02:00
ras
rdma RDMA v7.2 merge window 2026-06-18 08:16:21 -07:00
rv
scsi SCSI fixes on 20260802 2026-08-02 09:32:07 -07:00
soc soc/tegra: pmc: Fixes for v7.2 2026-07-10 14:40:52 +02:00
sound ASoC: SDCA: Move kcontrol search out of IRQ 2026-07-27 18:47:09 +01:00
target
trace mm/memory-failure: trace: change memory_failure_event to ras subsystem 2026-07-09 15:48:56 -07:00
uapi landlock: Add LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS 2026-08-15 09:14:46 +02:00
ufs Merge branch 7.1/scsi-fixes into 7.2/scsi-staging 2026-06-15 21:01:30 -04:00
vdso
video
xen xen: Replace __ASSEMBLY__ with __ASSEMBLER__ in header files 2026-07-01 09:49:52 +02:00
Kbuild