feat(arm32): add spectrev1 mitigation detection

This commit is contained in:
Stéphane Lesimple 2018-08-01 21:30:13 +02:00
parent 84195689af
commit cb740397f3

View File

@ -1977,7 +1977,7 @@ check_variant1_linux()
fi
if [ "$opt_sysfs_only" != 1 ]; then
# no /sys interface (or offline mode), fallback to our own ways
_info_nol "* Kernel has array_index_mask_nospec (x86): "
_info_nol "* Kernel has array_index_mask_nospec: "
# vanilla: look for the Linus' mask aka array_index_mask_nospec()
# that is inlined at least in raw_copy_from_user (__get_user_X symbols)
#mov PER_CPU_VAR(current_task), %_ASM_DX
@ -1989,6 +1989,22 @@ check_variant1_linux()
#ASM_STAC
# x86 64bits: jae(0x0f 0x83 0x?? 0x?? 0x?? 0x??) sbb(0x48 0x19 0xd2) and(0x48 0x21 0xd0)
# x86 32bits: cmp(0x3b 0x82 0x?? 0x?? 0x00 0x00) jae(0x73 0x??) sbb(0x19 0xd2) and(0x21 0xd0)
#
# arm32
##ifdef CONFIG_THUMB2_KERNEL
##define CSDB ".inst.w 0xf3af8014"
##else
##define CSDB ".inst 0xe320f014" e320f014
##endif
#asm volatile(
# "cmp %1, %2\n" e1500003
#" sbc %0, %1, %1\n" e0c03000
#CSDB
#: "=r" (mask)
#: "r" (idx), "Ir" (sz)
#: "cc");
#
# http://git.arm.linux.org.uk/cgit/linux-arm.git/commit/?h=spectre&id=a78d156587931a2c3b354534aa772febf6c9e855
if [ -n "$kernel_err" ]; then
pstatus yellow UNKNOWN "couldn't check ($kernel_err)"
elif ! which perl >/dev/null 2>&1; then
@ -1996,15 +2012,21 @@ check_variant1_linux()
else
perl -ne '/\x0f\x83....\x48\x19\xd2\x48\x21\xd0/ and $found++; END { exit($found) }' "$kernel"; ret=$?
if [ $ret -gt 0 ]; then
pstatus green YES "$ret occurrence(s) found of 64 bits array_index_mask_nospec()"
v1_mask_nospec="64 bits array_index_mask_nospec"
pstatus green YES "$ret occurrence(s) found of x86 64 bits array_index_mask_nospec()"
v1_mask_nospec="x86 64 bits array_index_mask_nospec"
else
perl -ne '/\x3b\x82..\x00\x00\x73.\x19\xd2\x21\xd0/ and $found++; END { exit($found) }' "$kernel"; ret=$?
if [ $ret -gt 0 ]; then
pstatus green YES "$ret occurrence(s) found of 32 bits array_index_mask_nospec()"
v1_mask_nospec="32 bits array_index_mask_nospec"
pstatus green YES "$ret occurrence(s) found of x86 32 bits array_index_mask_nospec()"
v1_mask_nospec="x86 32 bits array_index_mask_nospec"
else
pstatus yellow NO
ret=$("${opt_arch_prefix}objdump" -d "$kernel" | grep -w -e f3af8014 -e e320f014 -B2 | grep -B1 -w sbc | grep -w -c cmp)
if [ "$ret" -gt 0 ]; then
pstatus green YES "$ret occurrence(s) found of arm 32 bits array_index_mask_nospec()"
v1_mask_nospec="arm 32 bits array_index_mask_nospec"
else
pstatus yellow NO
fi
fi
fi
fi
@ -2023,7 +2045,7 @@ check_variant1_linux()
pstatus yellow NO
fi
_info_nol "* Kernel has mask_nospec64 (arm): "
_info_nol "* Kernel has mask_nospec64 (arm64): "
#.macro mask_nospec64, idx, limit, tmp
#sub \tmp, \idx, \limit
#bic \tmp, \tmp, \idx
@ -2050,13 +2072,12 @@ check_variant1_linux()
"${opt_arch_prefix}objdump" -d "$kernel" | perl -ne 'push @r, $_; /\s(hint|csdb)\s/ && $r[0]=~/\ssub\s+(x\d+)/ && $r[1]=~/\sbic\s+$1,\s+$1,/ && $r[2]=~/\sand\s/ && exit(9); shift @r if @r>3'; ret=$?
if [ "$ret" -eq 9 ]; then
pstatus green YES "mask_nospec64 macro is present and used"
v1_mask_nospec="arm mask_nospec64"
v1_mask_nospec="arm64 mask_nospec64"
else
pstatus yellow NO
fi
fi
if [ "$opt_verbose" -ge 2 ] || ( [ -z "$v1_mask_nospec" ] && [ "$redhat_canonical_spectre" != 1 ] && [ "$redhat_canonical_spectre" != 2 ] ); then
# this is a slow heuristic and we don't need it if we already know the kernel is patched
# but still show it in verbose mode