linux-stable/arch
Russell Currey f2c7e3562b powerpc/mm: Fix false detection of read faults
To support detection of read faults with Radix execute-only memory, the
vma_is_accessible() check in access_error() (which checks for PROT_NONE)
was replaced with a check to see if VM_READ was missing, and if so,
returns true to assert the fault was caused by a bad read.

This is incorrect, as it ignores that both VM_WRITE and VM_EXEC imply
read on powerpc, as defined in protection_map[].  This causes mappings
containing VM_WRITE or VM_EXEC without VM_READ to misreport the cause of
page faults, since the MMU is still allowing reads.

Correct this by restoring the original vma_is_accessible() check for
PROT_NONE mappings, and adding a separate check for Radix PROT_EXEC-only
mappings.

Fixes: 395cac7752 ("powerpc/mm: Support execute-only memory on the Radix MMU")
Reported-by: Michal Suchánek <msuchanek@suse.de>
Link: https://lore.kernel.org/r/20230308152702.GR19419@kitsune.suse.cz
Tested-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230310050834.63105-1-ruscur@russell.cc
2023-03-15 20:48:53 +11:00
..
alpha alpha: fix lazy-FPU mis(merged/applied/whatnot) 2023-03-06 20:13:49 -05:00
arc - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
arm ARM: SoC fixes for 6.3, part 1 2023-02-27 10:09:40 -08:00
arm64 arm64 fixes: 2023-03-02 14:57:53 -08:00
csky rch/csky patches for 6.3 2023-02-27 09:27:31 -08:00
hexagon VM_FAULT_RETRY fixes 2023-03-05 11:07:58 -08:00
ia64 cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
loongarch LoongArch changes for v6.3 2023-03-01 09:27:00 -08:00
m68k m68k: Only force 030 bus error if PC not in exception table 2023-03-06 14:09:42 +01:00
microblaze VM_FAULT_RETRY fixes 2023-03-05 11:07:58 -08:00
mips Networking fixes for 6.3-rc2, including fixes from netfilter, bpf 2023-03-09 10:56:58 -08:00
nios2 VM_FAULT_RETRY fixes 2023-03-05 11:07:58 -08:00
openrisc VM_FAULT_RETRY fixes 2023-03-05 11:07:58 -08:00
parisc VM_FAULT_RETRY fixes 2023-03-05 11:07:58 -08:00
powerpc powerpc/mm: Fix false detection of read faults 2023-03-15 20:48:53 +11:00
riscv RISC-V Fixes for 6.3-rc2 2023-03-10 09:19:30 -08:00
s390 s390 updates for 6.3 merge window part 2 2023-03-03 09:38:01 -08:00
sh sh: sanitize the flags on sigreturn 2023-03-09 10:01:59 -08:00
sparc VM_FAULT_RETRY fixes 2023-03-05 11:07:58 -08:00
um This pull request contains the following changes for UML: 2023-03-01 09:13:00 -08:00
x86 - Disable XSAVES on AMD Zen1 and Zen2 machines due to an erratum. No 2023-03-12 09:12:03 -07:00
xtensa - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
.gitignore
Kconfig arch/Kconfig: fix indentation 2023-02-09 17:03:20 -08:00