android_kernel_oneplus_msm8998/arch/x86/entry
Mathias Krause f1c5d01635 x86/vdso: Ensure vdso32_enabled gets set to valid values only
commit c06989da39cdb10604d572c8c7ea8c8c97f3c483 upstream.

vdso_enabled can be set to arbitrary integer values via the kernel command
line 'vdso32=' parameter or via 'sysctl abi.vsyscall32'.

load_vdso32() only maps VDSO if vdso_enabled == 1, but ARCH_DLINFO_IA32
merily checks for vdso_enabled != 0. As a consequence the AT_SYSINFO_EHDR
auxiliary vector for the VDSO_ENTRY is emitted with a NULL pointer which
causes a segfault when the application tries to use the VDSO.

Restrict the valid arguments on the command line and the sysctl to 0 and 1.

Fixes: b0b49f2673 ("x86, vdso: Remove compat vdso support")
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roland McGrath <roland@redhat.com>
Link: http://lkml.kernel.org/r/1491424561-7187-1-git-send-email-minipli@googlemail.com
Link: http://lkml.kernel.org/r/20170410151723.518412863@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-21 09:30:05 +02:00
..
syscalls x86/syscalls/64: Add compat_sys_keyctl for 32-bit userspace 2016-08-16 09:30:50 +02:00
vdso x86/vdso: Ensure vdso32_enabled gets set to valid values only 2017-04-21 09:30:05 +02:00
vsyscall x86/entry/vsyscall: Fix undefined symbol warning 2015-09-21 09:56:59 +02:00
calling.h x86/asm/entry/64: Save all regs on interrupt entry 2015-07-07 10:59:07 +02:00
common.c x86/entry/compat: Keep TS_COMPAT set during signal delivery 2016-04-12 09:08:32 -07:00
entry_32.S ftrace/x86_32: Set ftrace_stub to weak to prevent gcc from using short jumps to it 2017-01-09 08:07:50 +01:00
entry_64.S x86/entry/64: Fix irqflag tracing wrt context tracking 2015-11-24 09:55:02 +01:00
entry_64_compat.S x86/entry/compat: Add missing CLAC to entry_INT80_32 2016-03-03 15:07:30 -08:00
Makefile x86/entry: Move C entry and exit code to arch/x86/entry/common.c 2015-07-07 10:59:05 +02:00
syscall_32.c x86/syscalls: Give sys_call_ptr_t a useful type 2015-10-09 09:41:08 +02:00
syscall_64.c x86/syscalls: Give sys_call_ptr_t a useful type 2015-10-09 09:41:08 +02:00
thunk_32.S Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-06-22 17:59:09 -07:00
thunk_64.S Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-06-22 17:59:09 -07:00