linux_dsm_epyc7002/arch
Naveen N. Rao 5e5e63bacb powerpc/kprobes: Fix validation of prefixed instructions across page boundary
commit 82123a3d1d5a306fdf50c968a474cc60fe43a80f upstream.

When checking if the probed instruction is the suffix of a prefixed
instruction, we access the instruction at the previous word. If the
probed instruction is the very first word of a module, we can end up
trying to access an invalid page.

Fix this by skipping the check for all instructions at the beginning of
a page. Prefixed instructions cannot cross a 64-byte boundary and as
such, we don't expect to encounter a suffix as the very first word in a
page for kernel text. Even if there are prefixed instructions crossing
a page boundary (from a module, for instance), the instruction will be
illegal, so preventing probing on the suffix of such prefix instructions
isn't worthwhile.

Fixes: b4657f7650 ("powerpc/kprobes: Don't allow breakpoints on suffixes")
Cc: stable@vger.kernel.org # v5.8+
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0df9a032a05576a2fa8e97d1b769af2ff0eafbd6.1621416666.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-10 13:39:27 +02:00
..
alpha local64.h: make <asm/local64.h> mandatory 2021-01-12 20:18:16 +01:00
arc ARC: mm: Use max_high_pfn as a HIGHMEM zone border 2021-05-19 10:13:10 +02:00
arm ARM: dts: imx6q-dhcom: Add PU,VDD1P1,VDD2P5 regulators 2021-06-10 13:39:25 +02:00
arm64 arm64: dts: freescale: sl28: var4: fix RGMII clock and voltage 2021-06-10 13:39:22 +02:00
c6x arch-cleanup-2020-10-22 2020-10-23 10:06:38 -07:00
csky csky: change a Kconfig symbol name to fix e1000 build error 2021-04-28 13:40:02 +02:00
h8300 h8300: fix PREEMPTION build, TI_PRE_COUNT undefined 2021-02-17 11:02:28 +01:00
hexagon local64.h: make <asm/local64.h> mandatory 2021-01-12 20:18:16 +01:00
ia64 tweewide: Fix most Shebang lines 2021-05-22 11:40:55 +02:00
m68k m68k: Add missing mmap_read_lock() to sys_cacheflush() 2021-05-14 09:50:19 +02:00
microblaze local64.h: make <asm/local64.h> mandatory 2021-01-12 20:18:16 +01:00
mips MIPS: ralink: export rt_sysc_membase for rt2880_wdt.c 2021-06-03 09:00:50 +02:00
nds32 nds32: flush_dcache_page: use page_mapping_file to avoid races with swapoff 2021-04-14 08:41:58 +02:00
nios2 nios2: fixed broken sys_clone syscall 2021-03-04 11:38:16 +01:00
openrisc openrisc: Define memory barrier mb 2021-06-03 09:00:44 +02:00
parisc parisc: avoid a warning on u8 cast for cmpxchg on u8 pointers 2021-04-14 08:41:59 +02:00
powerpc powerpc/kprobes: Fix validation of prefixed instructions across page boundary 2021-06-10 13:39:27 +02:00
riscv riscv: vdso: fix and clean-up Makefile 2021-06-10 13:39:22 +02:00
s390 KVM: s390: extend kvm_s390_shadow_fault to return entry pointer 2021-05-14 09:50:03 +02:00
sh sh: Remove unused HAVE_COPY_THREAD_TLS macro 2021-01-27 11:55:20 +01:00
sparc sparc64: Fix opcode filtering in handling of no fault loads 2021-03-30 14:31:50 +02:00
um um: Disable CONFIG_GCOV with MODULES 2021-05-22 11:40:53 +02:00
x86 x86/apic: Mark _all_ legacy interrupts when IO/APIC is missing 2021-06-10 13:39:27 +02:00
xtensa xtensa: move coprocessor_flush to the .text section 2021-04-07 15:00:09 +02:00
.gitignore
Kconfig fanotify: Fix sys_fanotify_mark() on native x86-32 2021-01-17 14:16:59 +01:00