android_kernel_oneplus_msm8998/arch
Maciej W. Rozycki bedcf2fa26 MIPS: prctl: Disallow FRE without FR with PR_SET_FP_MODE requests
commit 28e4213dd331e944e7fca1954a946829162ed9d4 upstream.

Having PR_FP_MODE_FRE (i.e. Config5.FRE) set without PR_FP_MODE_FR (i.e.
Status.FR) is not supported as the lone purpose of Config5.FRE is to
emulate Status.FR=0 handling on FPU hardware that has Status.FR=1
hardwired[1][2].  Also we do not handle this case elsewhere, and assume
throughout our code that TIF_HYBRID_FPREGS and TIF_32BIT_FPREGS cannot
be set both at once for a task, leading to inconsistent behaviour if
this does happen.

Return unsuccessfully then from prctl(2) PR_SET_FP_MODE calls requesting
PR_FP_MODE_FRE to be set with PR_FP_MODE_FR clear.  This corresponds to
modes allowed by `mips_set_personality_fp'.

References:

[1] "MIPS Architecture For Programmers, Vol. III: MIPS32 / microMIPS32
    Privileged Resource Architecture", Imagination Technologies,
    Document Number: MD00090, Revision 6.02, July 10, 2015, Table 9.69
    "Config5 Register Field Descriptions", p. 262

[2] "MIPS Architecture For Programmers, Volume III: MIPS64 / microMIPS64
    Privileged Resource Architecture", Imagination Technologies,
    Document Number: MD00091, Revision 6.03, December 22, 2015, Table
    9.72 "Config5 Register Field Descriptions", p. 288

Fixes: 9791554b45 ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS")
Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 4.0+
Patchwork: https://patchwork.linux-mips.org/patch/19327/
Signed-off-by: James Hogan <jhogan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-06 16:46:23 +02:00
..
alpha locking/xchg/alpha: Fix xchg() and cmpxchg() memory ordering bugs 2018-05-30 07:49:01 +02:00
arc ARC: Fix malformed ARC_EMUL_UNALIGNED default 2018-05-30 07:48:58 +02:00
arm arm: dts: socfpga: fix GIC PPI warning 2018-05-30 07:49:11 +02:00
arm64 arm64: lse: Add early clobbers to some input/output asm operands 2018-06-06 16:46:20 +02:00
avr32 avr32: off by one in at32_init_pio() 2016-10-07 15:23:45 +02:00
blackfin pinctrl: adi2: Fix Kconfig build problem 2017-12-20 10:05:00 +01:00
c6x c6x/ptrace: Remove useless PTRACE_SETREGSET implementation 2017-03-31 09:49:53 +02:00
cris cris: Only build flash rescue image if CONFIG_ETRAX_AXISFLASHMAP is selected 2017-01-12 11:22:48 +01:00
frv futex: Remove duplicated code and fix undefined behaviour 2018-05-26 08:48:50 +02:00
h8300 h8300/ptrace: Fix incorrect register transfer count 2017-03-31 09:49:53 +02:00
hexagon futex: Remove duplicated code and fix undefined behaviour 2018-05-26 08:48:50 +02:00
ia64 futex: Remove duplicated code and fix undefined behaviour 2018-05-26 08:48:50 +02:00
m32r m32r: fix __get_user() 2016-09-24 10:07:43 +02:00
m68k m68k: set dma and coherent masks for platform FEC ethernets 2018-05-30 07:49:09 +02:00
metag metag/uaccess: Check access_ok in strncpy_from_user 2017-05-25 14:30:16 +02:00
microblaze futex: Remove duplicated code and fix undefined behaviour 2018-05-26 08:48:50 +02:00
mips MIPS: prctl: Disallow FRE without FR with PR_SET_FP_MODE requests 2018-06-06 16:46:23 +02:00
mn10300 mn10300/misalignment: Use SIGSEGV SEGV_MAPERR to report a failed user copy 2018-02-16 20:09:47 +01:00
nios2 nios2: reserve boot memory for device tree 2017-04-12 12:38:34 +02:00
openrisc signal/openrisc: Fix do_unaligned_access to send the proper signal 2018-02-16 20:09:46 +01:00
parisc futex: Remove duplicated code and fix undefined behaviour 2018-05-26 08:48:50 +02:00
powerpc powerpc/64s: Clear PCR on boot 2018-06-06 16:46:20 +02:00
s390 s390/ftrace: use expoline for indirect branches 2018-05-30 07:49:17 +02:00
score score: fix copy_from_user() and friends 2016-09-24 10:07:44 +02:00
sh sh: New gcc support 2018-06-06 16:46:20 +02:00
sparc sparc64: Make atomic_xchg() an inline function rather than a macro. 2018-05-30 07:49:08 +02:00
tile futex: Remove duplicated code and fix undefined behaviour 2018-05-26 08:48:50 +02:00
um um: Use POSIX ucontext_t instead of struct ucontext 2018-04-24 09:32:08 +02:00
unicore32 pwm: Changes for v4.4-rc1 2015-11-11 09:16:10 -08:00
x86 x86/apic: Set up through-local-APIC mode on the boot CPU if 'noapic' specified 2018-05-30 07:49:16 +02:00
xtensa futex: Remove duplicated code and fix undefined behaviour 2018-05-26 08:48:50 +02:00
.gitignore
Kconfig kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00