linux/arch/arm/kernel/process.c, branch v4.9

ARM: use simpler API for random address requests

2016-10-11T22:06:32Z

Currently, all callers to randomize_range() set the length to 0 and calculate end by adding a constant to the start address. We can simplify the API to remove a bunch of needless checks and variables. Use the new randomize_addr(start, range) call to set the requested address. Link: http://lkml.kernel.org/r/20160803233913.32511-4-jason@lakedaemon.net Signed-off-by: Jason Cooper Acked-by: Kees Cook Cc: "Russell King - ARM Linux" Cc: "Theodore Ts'o" Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ARM: save and reset the address limit when entering an exception

2016-07-07T15:01:01Z

When we enter an exception, the current address limit should not apply to the exception context: if the exception context wishes to access kernel space via the user accessors (eg, perf code), it must explicitly request such access. Acked-by: Will Deacon Signed-off-by: Russell King

ARM: get rid of horrible (unsigned int )(regs + 1)

2016-06-22T18:55:05Z

Get rid of the horrible "*(unsigned int *)(regs + 1)" to get at the parent context domain access register value, instead using the newly introduced svc_pt_regs structure. Acked-by: Will Deacon Signed-off-by: Russell King

vdso: make arch_setup_additional_pages wait for mmap_sem for write killable

2016-05-24T00:04:14Z

most architectures are relying on mmap_sem for write in their arch_setup_additional_pages. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Signed-off-by: Michal Hocko Acked-by: Andy Lutomirski [x86 vdso] Acked-by: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

exit_thread: accept a task parameter to be exited

2016-05-21T00:58:30Z

We need to call exit_thread from copy_process in a fail path. So make it accept task_struct as a parameter. [v2] * s390: exit_thread_runtime_instr doesn't make sense to be called for non-current tasks. * arm: fix the comment in vfp_thread_copy * change 'me' to 'tsk' for task_struct * now we can change only archs that actually have exit_thread [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Jiri Slaby Cc: "David S. Miller" Cc: "H. Peter Anvin" Cc: "James E.J. Bottomley" Cc: Aurelien Jacquiot Cc: Benjamin Herrenschmidt Cc: Catalin Marinas Cc: Chen Liqin Cc: Chris Metcalf Cc: Chris Zankel Cc: David Howells Cc: Fenghua Yu Cc: Geert Uytterhoeven Cc: Guan Xuetao Cc: Haavard Skinnemoen Cc: Hans-Christian Egtvedt Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: James Hogan Cc: Jeff Dike Cc: Jesper Nilsson Cc: Jiri Slaby Cc: Jonas Bonn Cc: Koichi Yasutake Cc: Lennox Wu Cc: Ley Foon Tan Cc: Mark Salter Cc: Martin Schwidefsky Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Mikael Starvik Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Ralf Baechle Cc: Rich Felker Cc: Richard Henderson Cc: Richard Kuo Cc: Richard Weinberger Cc: Russell King Cc: Steven Miao Cc: Thomas Gleixner Cc: Tony Luck Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ARM: report proper DACR value in oops dumps

2015-12-04T19:20:48Z

When printing the DACR value, we print the domain register value. This is incorrect, as with SW_PAN enabled, that is the current setting, rather than the faulting context's setting. Arrange to print the faulting domain's saved DACR value instead. Signed-off-by: Russell King

Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

2015-09-14T19:24:10Z

Pull ARM fixes from Russell King: "A number of fixes for the merge window, fixing a number of cases missed when testing the uaccess code, particularly cases which only show up with certain compiler versions" * 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: ARM: 8431/1: fix alignement of __bug_table section entries arm/xen: Enable user access to the kernel before issuing a privcmd call ARM: domains: add memory dependencies to get_domain/set_domain ARM: domains: thread_info.h no longer needs asm/domains.h ARM: uaccess: fix undefined instruction on ARMv7M/noMMU ARM: uaccess: remove unneeded uaccess_save_and_disable macro ARM: swpan: fix nwfpe for uaccess changes ARM: 8429/1: disable GCC SRA optimization

ARM: uaccess: fix undefined instruction on ARMv7M/noMMU

2015-09-09T22:26:44Z

The use of get_domain() in copy_thread() results in an oops on ARMv7M/noMMU systems. The thread cpu_domain value is only used when CONFIG_CPU_USE_DOMAINS is enabled, so there's no need to save the value in copy_thread() except when this is enabled, and this option will never be enabled on these platforms. Unhandled exception: IPSR = 00000006 LR = fffffff1 CPU: 0 PID: 0 Comm: swapper Not tainted 4.2.0-next-20150909-00001-gb8ec5ad #41 Hardware name: NXP LPC18xx/43xx (Device Tree) task: 2823fbe0 ti: 2823c000 task.ti: 2823c000 PC is at copy_thread+0x18/0x92 LR is at copy_thread+0x19/0x92 pc : [<2800a46e>] lr : [<2800a46f>] psr: 4100000b sp : 2823df00 ip : 00000000 fp : 287c81c0 r10: 00000000 r9 : 00800300 r8 : 287c8000 r7 : 287c8000 r6 : 2818908d r5 : 00000000 r4 : 287ca000 r3 : 00000000 r2 : 00000000 r1 : fffffff0 r0 : 287ca048 xPSR: 4100000b Reported-by: Ariel D'Alessandro Signed-off-by: Russell King

Merge branches 'cleanup', 'fixes', 'misc', 'omap-barrier' and 'uaccess' into for-linus

2015-09-03T14:28:37Z

ARM: software-based priviledged-no-access support

2015-08-26T19:34:24Z

Provide a software-based implementation of the priviledged no access support found in ARMv8.1. Userspace pages are mapped using a different domain number from the kernel and IO mappings. If we switch the user domain to "no access" when we enter the kernel, we can prevent the kernel from touching userspace. However, the kernel needs to be able to access userspace via the various user accessor functions. With the wrapping in the previous patch, we can temporarily enable access when the kernel needs user access, and re-disable it afterwards. This allows us to trap non-intended accesses to userspace, eg, caused by an inadvertent dereference of the LIST_POISON* values, which, with appropriate user mappings setup, can be made to succeed. This in turn can allow use-after-free bugs to be further exploited than would otherwise be possible. Signed-off-by: Russell King