Dan Williams 1715ebe370 /dev/mem: Revoke mappings when a driver claims the region ... [ Upstream commit 3234ac664a870e6ea69ae3a57d824cd7edbeacc5 ] Close the hole of holding a mapping over kernel driver takeover event of a given address range. Commit 90a545e98126 ("restrict /dev/mem to idle io memory ranges") introduced CONFIG_IO_STRICT_DEVMEM with the goal of protecting the kernel against scenarios where a /dev/mem user tramples memory that a kernel driver owns. However, this protection only prevents *new* read(), write() and mmap() requests. Established mappings prior to the driver calling request_mem_region() are left alone. Especially with persistent memory, and the core kernel metadata that is stored there, there are plentiful scenarios for a /dev/mem user to violate the expectations of the driver and cause amplified damage. Teach request_mem_region() to find and shoot down active /dev/mem mappings that it believes it has successfully claimed for the exclusive use of the driver. Effectively a driver call to request_mem_region() becomes a hole-punch on the /dev/mem device. The typical usage of unmap_mapping_range() is part of truncate_pagecache() to punch a hole in a file, but in this case the implementation is only doing the "first half" of a hole punch. Namely it is just evacuating current established mappings of the "hole", and it relies on the fact that /dev/mem establishes mappings in terms of absolute physical address offsets. Once existing mmap users are invalidated they can attempt to re-establish the mapping, or attempt to continue issuing read(2) / write(2) to the invalidated extent, but they will then be subject to the CONFIG_IO_STRICT_DEVMEM checking that can block those subsequent accesses. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 90a545e98126 ("restrict /dev/mem to idle io memory ranges") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/159009507306.847224.8502634072429766747.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-03-16 16:30:25 +08:00
..
bpf	bpf: Fix map permissions check	2021-03-16 16:29:38 +08:00
cgroup	Revert "cgroup: Add memory barriers to plug cgroup_rstat_updated() race window"	2021-03-16 16:28:43 +08:00
configs	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
debug	kgdb: Prevent infinite recursive entries to the debugger	2021-03-16 16:29:19 +08:00
dma	dma-direct: fix data truncation in dma_direct_get_required_mask()	2021-03-16 16:26:45 +08:00
events	perf: Add cond_resched() to task_function_call()	2021-03-16 16:29:12 +08:00
gcov	kernel/gcov/fs.c: gcov_seq_next() should increase position index	2021-03-16 16:26:46 +08:00
irq	genirq/irqdomain: Check pointer in irq_domain_alloc_irqs_hierarchy()	2021-03-16 16:25:58 +08:00
livepatch	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
locking	locktorture: Print ratio of acquisitions, not failures	2021-03-16 16:26:41 +08:00
power	PM: hibernate: Freeze kernel threads in software_resume()	2021-03-16 16:27:20 +08:00
printk	printk: queue wake_up_klogd irq_work only if per-CPU areas are ready	2021-03-16 16:27:05 +08:00
rcu	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
sched	sched: Defend cfs and rt bandwidth quota against overflow	2021-03-16 16:29:33 +08:00
time	time/sched_clock: Expire timer in hardirq context	2021-03-16 16:25:56 +08:00
tkernel	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
trace	Stop the ad-hoc games with -Wno-maybe-initialized	2021-03-16 16:27:58 +08:00
.gitignore	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kconfig.freezer	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kconfig.hz	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kconfig.locks	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kconfig.preempt	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Makefile	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
acct.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
async.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
audit.c	audit: fix a net reference leak in audit_list_rules_send()	2021-03-16 16:29:25 +08:00
audit.h	audit: fix a net reference leak in audit_list_rules_send()	2021-03-16 16:29:25 +08:00
audit_fsnotify.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
audit_tree.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
audit_watch.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
auditfilter.c	audit: fix a net reference leak in audit_list_rules_send()	2021-03-16 16:29:25 +08:00
auditsc.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
backtracetest.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
bounds.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
capability.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
compat.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
configs.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
context_tracking.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
cpu.c	sched/core: Fix illegal RCU from offline CPUs	2021-03-16 16:29:26 +08:00
cpu_pm.c	kernel/cpu_pm: Fix uninitted local in cpu_pm	2021-03-16 16:29:48 +08:00
crash_core.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
crash_dump.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
cred.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
delayacct.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
dma.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
elfcore.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
exec_domain.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
exit.c	exit: Move preemption fixup up, move blocking operations down	2021-03-16 16:29:26 +08:00
extable.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
fail_function.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
fork.c	fork: prevent accidental access to clone3 features	2021-03-16 16:27:54 +08:00
freezer.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
futex.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
gen_kheaders.sh	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
groups.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
hung_task.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
iomem.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
irq_work.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
jump_label.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kallsyms.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kcmp.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kcov.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kexec.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kexec_core.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kexec_elf.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kexec_file.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kexec_internal.h	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kheaders.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kmod.c	kmod: make request_module() return an error when autoloading is disabled	2021-03-16 16:26:15 +08:00
kprobes.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
ksysfs.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
kthread.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
latencytop.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
module-internal.h	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
module.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
module_signature.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
module_signing.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
notifier.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
nsproxy.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
padata.c	padata: add separate cpuhp node for CPUHP_PADATA_DEAD	2021-03-16 16:28:57 +08:00
panic.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
params.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
pid.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
pid_namespace.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
profile.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
ptrace.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
range.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
reboot.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
relay.c	kernel/relay.c: handle alloc_percpu returning NULL in relay_open	2021-03-16 16:28:44 +08:00
resource.c	/dev/mem: Revoke mappings when a driver claims the region	2021-03-16 16:30:25 +08:00
rseq.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
seccomp.c	seccomp: Add missing compat_ioctl for notify	2021-03-16 16:26:02 +08:00
signal.c	signal: check sig before setting info in kill_pid_usb_asyncio	2021-03-16 16:27:12 +08:00
smp.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
smpboot.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
smpboot.h	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
softirq.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
stackleak.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
stacktrace.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
stop_machine.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
sys.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
sys_ni.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
sysctl.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
sysctl_binary.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
task_work.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
taskstats.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
test_kprobes.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
torture.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
tracepoint.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
tsacct.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
ucount.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
uid16.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
uid16.h	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
umh.c	umh: fix memory leak on execve failure	2021-03-16 16:27:49 +08:00
up.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
user-return-notifier.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
user.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
user_namespace.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
utsname.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
utsname_sysctl.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
watchdog.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
watchdog_hld.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
workqueue.c	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
workqueue_internal.h	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00