linux-stable.git/arch/arm, branch v3.2.98 Linux kernel stable tree ARM: 8720/1: ensure dump_instr() checks addr_limit 2018-01-01T20:51:02+00:00 Mark Rutland mark.rutland@arm.com 2017-11-02T17:44:28+00:00 1e7e03e81806836de6078d15d41af7ad5ee301cf commit b9dd05c7002ee0ca8b676428b2268c26399b5e31 upstream. When CONFIG_DEBUG_USER is enabled, it's possible for a user to deliberately trigger dump_instr() with a chosen kernel address. Let's avoid problems resulting from this by using get_user() rather than __get_user(), ensuring that we don't erroneously access kernel memory. So that we can use the same code to dump user instructions and kernel instructions, the common dumping code is factored out to __dump_instr(), with the fs manipulated appropriately in dump_instr() around calls to this. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit b9dd05c7002ee0ca8b676428b2268c26399b5e31 upstream.

When CONFIG_DEBUG_USER is enabled, it's possible for a user to
deliberately trigger dump_instr() with a chosen kernel address.

Let's avoid problems resulting from this by using get_user() rather than
__get_user(), ensuring that we don't erroneously access kernel memory.

So that we can use the same code to dump user instructions and kernel
instructions, the common dumping code is factored out to __dump_instr(),
with the fs manipulated appropriately in dump_instr() around calls to
this.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: 8160/1: drop warning about return_address not using unwind tables 2017-11-11T13:34:51+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2014-09-24T07:51:57+00:00 747ea873db4fb9836bacfdc6f4d7d7d11d3d808d commit e16343c47e4276f5ebc77ca16feb5e50ca1918f9 upstream. The warning was introduced in 2009 (commit 4bf1fa5a34aa ([ARM] 5613/1: implement CALLER_ADDRESSx)). The only "problem" here is that CALLER_ADDRESSx for x > 1 returns NULL which doesn't do much harm. The drawback of implementing a fix (i.e. use unwind tables to implement CALLER_ADDRESSx) is that much of the unwinder code would need to be marked as not traceable. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit e16343c47e4276f5ebc77ca16feb5e50ca1918f9 upstream.

The warning was introduced in 2009 (commit 4bf1fa5a34aa ([ARM] 5613/1:
implement CALLER_ADDRESSx)). The only "problem" here is that
CALLER_ADDRESSx for x > 1 returns NULL which doesn't do much harm.

The drawback of implementing a fix (i.e. use unwind tables to implement CALLER_ADDRESSx) is that much of the unwinder code would need to be marked as not
traceable.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: pxa: select both FB and FB_W100 for eseries 2017-11-11T13:34:27+00:00 Arnd Bergmann arnd@arndb.de 2014-03-19T17:41:37+00:00 7994d69893ffffa96dd81b2b63246f92e89fa4c8 commit 1d20d8a9fce8f1e2ef00a0f3d068fa18d59ddf8f upstream. We get a link error trying to access the w100fb_gpio_read/write functions from the platform when the driver is a loadable module or not built-in, so the platform already uses 'select' to hard-enable the driver. However, that fails if the framebuffer subsystem is disabled altogether. I've considered various ways to fix this properly, but they all seem like too much work or too risky, so this simply adds another 'select' to force the subsystem on as well. Fixes: 82427de2c7c3 ("ARM: pxa: PXA_ESERIES depends on FB_W100.") Signed-off-by: Arnd Bergmann <arnd@arndb.de> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 1d20d8a9fce8f1e2ef00a0f3d068fa18d59ddf8f upstream.

We get a link error trying to access the w100fb_gpio_read/write
functions from the platform when the driver is a loadable module
or not built-in, so the platform already uses 'select' to hard-enable
the driver.

However, that fails if the framebuffer subsystem is disabled
altogether.

I've considered various ways to fix this properly, but they
all seem like too much work or too risky, so this simply
adds another 'select' to force the subsystem on as well.

Fixes: 82427de2c7c3 ("ARM: pxa: PXA_ESERIES depends on FB_W100.")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
mm: larger stack guard gap, between vmas 2017-07-02T16:12:47+00:00 Hugh Dickins hughd@google.com 2017-06-19T18:32:47+00:00 640c7dfdc7c723143b1ce42f5569ec8565cbbde7 commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream. Stack guard page is a useful feature to reduce a risk of stack smashing into a different mapping. We have been using a single page gap which is sufficient to prevent having stack adjacent to a different mapping. But this seems to be insufficient in the light of the stack usage in userspace. E.g. glibc uses as large as 64kB alloca() in many commonly used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX] which is 256kB or stack strings with MAX_ARG_STRLEN. This will become especially dangerous for suid binaries and the default no limit for the stack size limit because those applications can be tricked to consume a large portion of the stack and a single glibc call could jump over the guard page. These attacks are not theoretical, unfortunatelly. Make those attacks less probable by increasing the stack guard gap to 1MB (on systems with 4k pages; but make it depend on the page size because systems with larger base pages might cap stack allocations in the PAGE_SIZE units) which should cover larger alloca() and VLA stack allocations. It is obviously not a full fix because the problem is somehow inherent, but it should reduce attack space a lot. One could argue that the gap size should be configurable from userspace, but that can be done later when somebody finds that the new 1MB is wrong for some special case applications. For now, add a kernel command line option (stack_guard_gap) to specify the stack gap size (in page units). Implementation wise, first delete all the old code for stack guard page: because although we could get away with accounting one extra page in a stack vma, accounting a larger gap can break userspace - case in point, a program run with "ulimit -S -v 20000" failed when the 1MB gap was counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK and strict non-overcommit mode. Instead of keeping gap inside the stack vma, maintain the stack guard gap as a gap between vmas: using vm_start_gap() in place of vm_start (or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few places which need to respect the gap - mainly arch_get_unmapped_area(), and and the vma tree's subtree_gap support for that. Original-patch-by: Oleg Nesterov <oleg@redhat.com> Original-patch-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Tested-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [Hugh Dickins: Backported to 3.2] [bwh: Fix more instances of vma->vm_start in sparc64 impl. of arch_get_unmapped_area_topdown() and generic impl. of hugetlb_get_unmapped_area()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream.

Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.

This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.

Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.

One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications.  For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).

Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.

Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.

Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Hugh Dickins: Backported to 3.2]
[bwh: Fix more instances of vma->vm_start in sparc64 impl. of
 arch_get_unmapped_area_topdown() and generic impl. of
 hugetlb_get_unmapped_area()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: 8643/3: arm/ptrace: Preserve previous registers for short regset write 2017-03-16T02:18:47+00:00 Dave Martin Dave.Martin@arm.com 2017-01-18T16:11:56+00:00 5dc6ade70fc80c2db8a77261df723f4bec761067 commit 228dbbfb5d77f8e047b2a1d78da14b7158433027 upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Fixes: 5be6f62b0059 ("ARM: 6883/1: ptrace: Migrate to regsets framework") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 228dbbfb5d77f8e047b2a1d78da14b7158433027 upstream.

Ensure that if userspace supplies insufficient data to
PTRACE_SETREGSET to fill all the registers, the thread's old
registers are preserved.

Fixes: 5be6f62b0059 ("ARM: 6883/1: ptrace: Migrate to regsets framework")
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: 8634/1: hw_breakpoint: blacklist Scorpion CPUs 2017-03-16T02:18:42+00:00 Mark Rutland mark.rutland@arm.com 2017-01-06T12:12:47+00:00 c1c5e50aa758cf5d2b91976dfc1aa6a56707c3f8 commit ddc37832a1349f474c4532de381498020ed71d31 upstream. On APQ8060, the kernel crashes in arch_hw_breakpoint_init, taking an undefined instruction trap within write_wb_reg. This is because Scorpion CPUs erroneously appear to set DBGPRSR.SPD when WFI is issued, even if the core is not powered down. When DBGPRSR.SPD is set, breakpoint and watchpoint registers are treated as undefined. It's possible to trigger similar crashes later on from userspace, by requesting the kernel to install a breakpoint or watchpoint, as we can go idle at any point between the reset of the debug registers and their later use. This has always been the case. Given that this has always been broken, no-one has complained until now, and there is no clear workaround, disable hardware breakpoints and watchpoints on Scorpion to avoid these issues. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> [bwh: Backported to 3.2: - Open-code read_cpuid_part() - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit ddc37832a1349f474c4532de381498020ed71d31 upstream.

On APQ8060, the kernel crashes in arch_hw_breakpoint_init, taking an
undefined instruction trap within write_wb_reg. This is because Scorpion
CPUs erroneously appear to set DBGPRSR.SPD when WFI is issued, even if
the core is not powered down. When DBGPRSR.SPD is set, breakpoint and
watchpoint registers are treated as undefined.

It's possible to trigger similar crashes later on from userspace, by
requesting the kernel to install a breakpoint or watchpoint, as we can
go idle at any point between the reset of the debug registers and their
later use. This has always been the case.

Given that this has always been broken, no-one has complained until now,
and there is no clear workaround, disable hardware breakpoints and
watchpoints on Scorpion to avoid these issues.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2:
 - Open-code read_cpuid_part()
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: dma-mapping: don't allow DMA mappings to be marked executable 2017-02-23T03:51:03+00:00 Russell King rmk+kernel@arm.linux.org.uk 2013-10-23T15:14:59+00:00 d05fedab817c43171d355d3aad5a9281ff80a7ba commit 0ea1ec713f04bdfac343c9702b21cd3a7c711826 upstream. DMA mapping permissions were being derived from pgprot_kernel directly without using PAGE_KERNEL. This causes them to be marked with executable permission, which is not what we want. Fix this. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 0ea1ec713f04bdfac343c9702b21cd3a7c711826 upstream.

DMA mapping permissions were being derived from pgprot_kernel directly
without using PAGE_KERNEL.  This causes them to be marked with executable
permission, which is not what we want.  Fix this.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: sa1111: fix pcmcia suspend/resume 2016-11-20T01:01:38+00:00 Russell King rmk+kernel@armlinux.org.uk 2016-09-06T13:34:05+00:00 b9590db438694507e4460abaff3340483bdcd7d7 commit 06dfe5cc0cc684e735cb0232fdb756d30780b05d upstream. SA1111 PCMCIA was broken when PCMCIA switched to using dev_pm_ops for the PCMCIA socket class. PCMCIA used to handle suspend/resume via the socket hosting device, which happened at normal device suspend/resume time. However, the referenced commit changed this: much of the resume now happens much earlier, in the noirq resume handler of dev_pm_ops. However, on SA1111, the PCMCIA device is not accessible as the SA1111 has not been resumed at _noirq time. It's slightly worse than that, because the SA1111 has already been put to sleep at _noirq time, so suspend doesn't work properly. Fix this by converting the core SA1111 code to use dev_pm_ops as well, and performing its own suspend/resume at noirq time. This fixes these errors in the kernel log: pcmcia_socket pcmcia_socket0: time out after reset pcmcia_socket pcmcia_socket1: time out after reset and the resulting lack of PCMCIA cards after a S2RAM cycle. Fixes: d7646f7632549 ("pcmcia: use dev_pm_ops for class pcmcia_socket_class") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 06dfe5cc0cc684e735cb0232fdb756d30780b05d upstream.

SA1111 PCMCIA was broken when PCMCIA switched to using dev_pm_ops for
the PCMCIA socket class.  PCMCIA used to handle suspend/resume via the
socket hosting device, which happened at normal device suspend/resume
time.

However, the referenced commit changed this: much of the resume now
happens much earlier, in the noirq resume handler of dev_pm_ops.

However, on SA1111, the PCMCIA device is not accessible as the SA1111
has not been resumed at _noirq time.  It's slightly worse than that,
because the SA1111 has already been put to sleep at _noirq time, so
suspend doesn't work properly.

Fix this by converting the core SA1111 code to use dev_pm_ops as well,
and performing its own suspend/resume at noirq time.

This fixes these errors in the kernel log:

pcmcia_socket pcmcia_socket0: time out after reset
pcmcia_socket pcmcia_socket1: time out after reset

and the resulting lack of PCMCIA cards after a S2RAM cycle.

Fixes: d7646f7632549 ("pcmcia: use dev_pm_ops for class pcmcia_socket_class")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
arm: oabi compat: add missing access checks 2016-11-20T01:01:32+00:00 Dave Weinstein olorin@google.com 2016-07-28T18:55:41+00:00 b1038b4e5e64547052f91767ddf369683ebf2697 commit 7de249964f5578e67b99699c5f0b405738d820a2 upstream. Add access checks to sys_oabi_epoll_wait() and sys_oabi_semtimedop(). This fixes CVE-2016-3857, a local privilege escalation under CONFIG_OABI_COMPAT. Reported-by: Chiachih Wu <wuchiachih@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Dave Weinstein <olorin@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 7de249964f5578e67b99699c5f0b405738d820a2 upstream.

Add access checks to sys_oabi_epoll_wait() and sys_oabi_semtimedop().
This fixes CVE-2016-3857, a local privilege escalation under
CONFIG_OABI_COMPAT.

Reported-by: Chiachih Wu <wuchiachih@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Dave Weinstein <olorin@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ARM: OMAP3: hwmod data: Add sysc information for DSI 2016-11-20T01:01:28+00:00 Sebastian Reichel sre@kernel.org 2016-06-24T01:59:33+00:00 ec2c9950bff350c230a29394c9d0edf375069dfb commit b46211d6dcfb81a8af66b8684a42d629183670d4 upstream. Add missing sysconfig/sysstatus information to OMAP3 hwmod. The information has been checked against OMAP34xx and OMAP36xx TRM. Without this change DSI block is not reset during boot, which is required for working Nokia N950 display. Signed-off-by: Sebastian Reichel <sre@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit b46211d6dcfb81a8af66b8684a42d629183670d4 upstream.

Add missing sysconfig/sysstatus information
to OMAP3 hwmod. The information has been
checked against OMAP34xx and OMAP36xx TRM.

Without this change DSI block is not reset
during boot, which is required for working
Nokia N950 display.

Signed-off-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>