commit 49275fef98 upstream.
The kernel is very erratic as to which pagetables have _PAGE_USER set. The
vsyscall page gets lucky: it seems that all of the relevant pagetables are
among the apparently arbitrary ones that set _PAGE_USER. Rather than
relying on chance, just explicitly set _PAGE_USER.
This will let us clean up pagetable setup to stop setting _PAGE_USER. The
added code can also be reused by pagetable isolation to manage the
_PAGE_USER bit in the usermode tables.
[ tglx: Folded paravirt fix from Juergen Gross ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 32d0b95300 upstream.
[note, only the inat.h portion, to get objtool back in sync - gregkh]
b0caa8c8c6bbc422bc3c32b64852d6d618f32b49 Mon Sep 17 00:00:00 2001
When computing a linear address and segmentation is used, we need to know
the base address of the segment involved in the computation. In most of
the cases, the segment base address will be zero as in USER_DS/USER32_DS.
However, it may be possible that a user space program defines its own
segments via a local descriptor table. In such a case, the segment base
address may not be zero. Thus, the segment base address is needed to
calculate correctly the linear address.
If running in protected mode, the segment selector to be used when
computing a linear address is determined by either any of segment override
prefixes in the instruction or inferred from the registers involved in the
computation of the effective address; in that order. Also, there are cases
when the segment override prefixes shall be ignored (i.e., code segments
are always selected by the CS segment register; string instructions always
use the ES segment register when using rDI register as operand). In long
mode, segment registers are ignored, except for FS and GS. In these two
cases, base addresses are obtained from the respective MSRs.
For clarity, this process can be split into four steps (and an equal
number of functions): determine if segment prefixes overrides can be used;
parse the segment override prefixes, and use them if found; if not found
or cannot be used, use the default segment registers associated with the
operand registers. Once the segment register to use has been identified,
read its value to obtain the segment selector.
The method to obtain the segment selector depends on several factors. In
32-bit builds, segment selectors are saved into a pt_regs structure
when switching to kernel mode. The same is also true for virtual-8086
mode. In 64-bit builds, segmentation is mostly ignored, except when
running a program in 32-bit legacy mode. In this case, CS and SS can be
obtained from pt_regs. DS, ES, FS and GS can be read directly from
the respective segment registers.
In order to identify the segment registers, a new set of #defines is
introduced. It also includes two special identifiers. One of them
indicates when the default segment register associated with instruction
operands shall be used. Another one indicates that the contents of the
segment register shall be ignored; this identifier is used when in long
mode.
Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: ricardo.neri@intel.com
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Qiaowei Ren <qiaowei.ren@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Garnier <thgarnie@google.com>
Link: https://lkml.kernel.org/r/1509135945-13762-14-git-send-email-ricardo.neri-calderon@linux.intel.com
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 14c47b54b0 upstream.
The new ORC unwinder breaks the build of a 64-bit kernel on a 32-bit
host. Building the kernel on a i386 or x32 host fails with:
orc_dump.c: In function 'orc_dump':
orc_dump.c:105:26: error: passing argument 2 of 'elf_getshdrnum' from incompatible pointer type [-Werror=incompatible-pointer-types]
if (elf_getshdrnum(elf, &nr_sections)) {
^
In file included from /usr/local/include/gelf.h:32:0,
from elf.h:22,
from warn.h:26,
from orc_dump.c:20:
/usr/local/include/libelf.h:304:12: note: expected 'size_t * {aka unsigned int *}' but argument is of type 'long unsigned int *'
extern int elf_getshdrnum (Elf *__elf, size_t *__dst);
^~~~~~~~~~~~~~
orc_dump.c:190:17: error: format '%lx' expects argument of type 'long unsigned int', but argument 3 has type 'Elf64_Sxword {aka long long int}' [-Werror=format=]
printf("%s+%lx:", name, rela.r_addend);
~~^ ~~~~~~~~~~~~~
%llx
Fix the build failure.
Another problem is that if the user specifies HOSTCC or HOSTLD
variables, they are ignored in the objtool makefile. Change the
Makefile to respect these variables.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sven Joachim <svenjoac@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 627fce1480 ("objtool: Add ORC unwind table generation")
Link: http://lkml.kernel.org/r/19f0e64d8e07e30a7b307cd010eb780c404fe08d.1512252895.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d15155824c upstream.
linux/compiler.h is included indirectly by linux/types.h via
uapi/linux/types.h -> uapi/linux/posix_types.h -> linux/stddef.h
-> uapi/linux/stddef.h and is needed to provide a proper definition of
offsetof.
Unfortunately, compiler.h requires a definition of
smp_read_barrier_depends() for defining lockless_dereference() and soon
for defining READ_ONCE(), which means that all
users of READ_ONCE() will need to include asm/barrier.h to avoid splats
such as:
In file included from include/uapi/linux/stddef.h:1:0,
from include/linux/stddef.h:4,
from arch/h8300/kernel/asm-offsets.c:11:
include/linux/list.h: In function 'list_empty':
>> include/linux/compiler.h:343:2: error: implicit declaration of function 'smp_read_barrier_depends' [-Werror=implicit-function-declaration]
smp_read_barrier_depends(); /* Enforce dependency ordering from x */ \
^
A better alternative is to include asm/barrier.h in linux/compiler.h,
but this requires a type definition for "bool" on some architectures
(e.g. x86), which is defined later by linux/types.h. Type "bool" is also
used directly in linux/compiler.h, so the whole thing is pretty fragile.
This patch splits compiler.h in two: compiler_types.h contains type
annotations, definitions and the compiler-specific parts, whereas
compiler.h #includes compiler-types.h and additionally defines macros
such as {READ,WRITE.ACCESS}_ONCE().
uapi/linux/stddef.h and linux/linkage.h are then moved over to include
linux/compiler_types.h, which fixes the build for h8 and blackfin.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1508840570-22169-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Jann Horn <jannh@google.com>
[ Upstream commit 2255f8d520 ]
These tests should cover the following cases:
- MOV with both zero-extended and sign-extended immediates
- implicit truncation of register contents via ALU32/MOV32
- implicit 32-bit truncation of ALU32 output
- oversized register source operand for ALU32 shift
- right-shift of a number that could be positive or negative
- map access where adding the operation size to the offset causes signed
32-bit overflow
- direct stack access at a ~4GiB offset
Also remove the F_LOAD_WITH_STRICT_ALIGNMENT flag from a bunch of tests
that should fail independent of what flags userspace passes.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Alexei Starovoitov <ast@kernel.org>
[ Upstream commit bb7f0f989c ]
There were various issues related to the limited size of integers used in
the verifier:
- `off + size` overflow in __check_map_access()
- `off + reg->off` overflow in check_mem_access()
- `off + reg->var_off.value` overflow or 32-bit truncation of
`reg->var_off.value` in check_mem_access()
- 32-bit truncation in check_stack_boundary()
Make sure that any integer math cannot overflow by not allowing
pointer math with large values.
Also reduce the scope of "scalar op scalar" tracking.
Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Jann Horn <jannh@google.com>
[ Upstream commit 179d1c5602 ]
This could be made safe by passing through a reference to env and checking
for env->allow_ptr_leaks, but it would only work one way and is probably
not worth the hassle - not doing it will not directly lead to program
rejection.
Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Jann Horn <jannh@google.com>
[ Upstream commit a5ec6ae161 ]
Force strict alignment checks for stack pointers because the tracking of
stack spills relies on it; unaligned stack accesses can lead to corruption
of spilled registers, which is exploitable.
Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Jann Horn <jannh@google.com>
[ Upstream commit 0c17d1d2c6 ]
Properly handle register truncation to a smaller size.
The old code first mirrors the clearing of the high 32 bits in the bitwise
tristate representation, which is correct. But then, it computes the new
arithmetic bounds as the intersection between the old arithmetic bounds and
the bounds resulting from the bitwise tristate representation. Therefore,
when coerce_reg_to_32() is called on a number with bounds
[0xffff'fff8, 0x1'0000'0007], the verifier computes
[0xffff'fff8, 0xffff'ffff] as bounds of the truncated number.
This is incorrect: The truncated number could also be in the range [0, 7],
and no meaningful arithmetic bounds can be computed in that case apart from
the obvious [0, 0xffff'ffff].
Starting with v4.14, this is exploitable by unprivileged users as long as
the unprivileged_bpf_disabled sysctl isn't set.
Debian assigned CVE-2017-16996 for this issue.
v2:
- flip the mask during arithmetic bounds calculation (Ben Hutchings)
v3:
- add CVE number (Ben Hutchings)
Fixes: b03c9f9fdc ("bpf/verifier: track signed and unsigned min/max values")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Jann Horn <jannh@google.com>
[ Upstream commit 95a762e2c8 ]
Distinguish between
BPF_ALU64|BPF_MOV|BPF_K (load 32-bit immediate, sign-extended to 64-bit)
and BPF_ALU|BPF_MOV|BPF_K (load 32-bit immediate, zero-padded to 64-bit);
only perform sign extension in the first case.
Starting with v4.14, this is exploitable by unprivileged users as long as
the unprivileged_bpf_disabled sysctl isn't set.
Debian assigned CVE-2017-16995 for this issue.
v3:
- add CVE number (Ben Hutchings)
Fixes: 484611357c ("bpf: allow access into map value arrays")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Edward Cree <ecree@solarflare.com>
[ Upstream commit 4374f256ce ]
Incorrect signed bounds were being computed.
If the old upper signed bound was positive and the old lower signed bound was
negative, this could cause the new upper signed bound to be too low,
leading to security issues.
Fixes: b03c9f9fdc ("bpf/verifier: track signed and unsigned min/max values")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
[jannh@google.com: changed description to reflect bug impact]
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 07aee94394 ]
When LD_ABS/IND is used in the program, and we have a BPF helper
call that changes packet data (bpf_helper_changes_pkt_data() returns
true), then in case of sparc JIT, we try to reload cached skb data
from bpf2sparc[BPF_REG_6]. However, there is no such guarantee or
assumption that skb sits in R6 at this point, all helpers changing
skb data only have a guarantee that skb sits in R1. Therefore,
store BPF R1 in L7 temporarily and after procedure call use L7 to
reload cached skb data. skb sitting in R6 is only true at the time
when LD_ABS/IND is executed.
Fixes: 7a12b5031c ("sparc64: Add eBPF JIT.")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 87338c8e2c ]
The assumption of unconditionally reloading skb pointers on
BPF helper calls where bpf_helper_changes_pkt_data() holds
true is wrong. There can be different contexts where the helper
would enforce a reload such as in case of XDP. Here, we do
have a struct xdp_buff instead of struct sk_buff as context,
thus this will access garbage.
JITs only ever need to deal with cached skb pointer reload
when ld_abs/ind was seen, therefore guard the reload behind
SEEN_SKB.
Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6d59b7dbf7 ]
The assumption of unconditionally reloading skb pointers on
BPF helper calls where bpf_helper_changes_pkt_data() holds
true is wrong. There can be different contexts where the
BPF helper would enforce a reload such as in case of XDP.
Here, we do have a struct xdp_buff instead of struct sk_buff
as context, thus this will access garbage.
JITs only ever need to deal with cached skb pointer reload
when ld_abs/ind was seen, therefore guard the reload behind
SEEN_SKB only. Tested on s390x.
Fixes: 9db7f2b818 ("s390/bpf: recache skb->data/hlen for skb_vlan_push/pop")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 283ca526a9 ]
When tracing and networking programs are both attached in the
system and both use event-output helpers that eventually call
into perf_event_output(), then we could end up in a situation
where the tracing attached program runs in user context while
a cls_bpf program is triggered on that same CPU out of softirq
context.
Since both rely on the same per-cpu perf_sample_data, we could
potentially corrupt it. This can only ever happen in a combination
of the two types; all tracing programs use a bpf_prog_active
counter to bail out in case a program is already running on
that CPU out of a different context. XDP and cls_bpf programs
by themselves don't have this issue as they run in the same
context only. Therefore, split both perf_sample_data so they
cannot be accessed from each other.
Fixes: 20b9d7ac48 ("bpf: avoid excessive stack usage for perf_sample_data")
Reported-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Song Liu <songliubraving@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
From: Alexei Starovoitov <ast@fb.com>
[ Upstream commit c131187db2 ]
when the verifier detects that register contains a runtime constant
and it's compared with another constant it will prune exploration
of the branch that is guaranteed not to be taken at runtime.
This is all correct, but malicious program may be constructed
in such a way that it always has a constant comparison and
the other branch is never taken under any conditions.
In this case such path through the program will not be explored
by the verifier. It won't be taken at run-time either, but since
all instructions are JITed the malicious program may cause JITs
to complain about using reserved fields, etc.
To fix the issue we have to track the instructions explored by
the verifier and sanitize instructions that are dead at run time
with NOPs. We cannot reject such dead code, since llvm generates
it for valid C code, since it doesn't do as much data flow
analysis as the verifier does.
Fixes: 17a5267067 ("bpf: verifier (add verifier core)")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bff5bf9db1 upstream.
Sending the switch state change twice within the same frame is invalid
evdev protocol and only works if the client handles keys immediately as
well. Processing events immediately is incorrect, it forces a fake
order of events that does not exist on the device.
Recent versions of libinput changed to only process the device state and
SYN_REPORT time, so now the key event is lost.
https://bugs.freedesktop.org/show_bug.cgi?id=104041
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit db2b033260 upstream.
The DT specifies a threshold of 65000, we setup the register with a value in
the temperature resolution for the controller, 64656.
When we reach 64656, the interrupt fires, the interrupt is disabled. Then the
irq thread runs and calls thermal_zone_device_update() which will call in turn
hisi_thermal_get_temp().
The function will look if the temperature decreased, assuming it was more than
65000, but that is not the case because the current temperature is 64656
(because of the rounding when setting the threshold). This condition being
true, we re-enable the interrupt which fires immediately after exiting the irq
thread. That happens again and again until the temperature goes to more than
65000.
Potentially, there is here an interrupt storm if the temperature stabilizes at
this temperature. A very unlikely case but possible.
In any case, it does not make sense to handle dozens of alarm interrupt for
nothing.
Fix this by rounding the threshold value to the controller resolution so the
check against the threshold is consistent with the one set in the controller.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Kevin Wangtao <kevin.wangtao@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
