From: Ard Biesheuvel ardb@kernel.org
mainline inclusion from mainline-5.11-rc1 commit aaac3733171fca948c4fb66b78257620e3885339 category: bugfix bugzilla: 46882 CVE: NA
------------------------------------------------- Replace the open coded calculations of the actual physical address of the KVM stub vector table with a single adr_l invocation.
Reviewed-by: Nicolas Pitre nico@fluxnic.net Signed-off-by: Ard Biesheuvel ardb@kernel.org (cherry picked from commit aaac3733171fca948c4fb66b78257620e3885339) Signed-off-by: Zhao Hongjiang zhaohongjiang@huawei.com --- arch/arm/boot/compressed/head.S | 15 ++------------- arch/arm/kernel/hyp-stub.S | 27 ++++++++++++--------------- 2 files changed, 14 insertions(+), 28 deletions(-)
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index 27b960108b8d..87d6be9340fe 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -468,15 +468,10 @@ dtb_check_done:
/* * Compute the address of the hyp vectors after relocation. - * This requires some arithmetic since we cannot directly - * reference __hyp_stub_vectors in a PC-relative way. * Call __hyp_set_vectors with the new address so that we * can HVC again after the copy. */ -0: adr r0, 0b - movw r1, #:lower16:__hyp_stub_vectors - 0b - movt r1, #:upper16:__hyp_stub_vectors - 0b - add r0, r0, r1 + adr_l r0, __hyp_stub_vectors sub r0, r0, r5 add r0, r0, r10 bl __hyp_set_vectors @@ -627,17 +622,11 @@ not_relocated: mov r0, #0 cmp r0, #HYP_MODE @ if not booted in HYP mode... bne __enter_kernel @ boot kernel directly
- adr r12, .L__hyp_reentry_vectors_offset - ldr r0, [r12] - add r0, r0, r12 - + adr_l r0, __hyp_reentry_vectors bl __hyp_set_vectors __HVC(0) @ otherwise bounce to hyp mode
b . @ should never be reached - - .align 2 -.L__hyp_reentry_vectors_offset: .long __hyp_reentry_vectors - . #else b __enter_kernel #endif diff --git a/arch/arm/kernel/hyp-stub.S b/arch/arm/kernel/hyp-stub.S index 26d8e03b1dd3..103d0bdb2b7e 100644 --- a/arch/arm/kernel/hyp-stub.S +++ b/arch/arm/kernel/hyp-stub.S @@ -24,41 +24,38 @@ ENTRY(__boot_cpu_mode) .text
/* - * Save the primary CPU boot mode. Requires 3 scratch registers. + * Save the primary CPU boot mode. Requires 2 scratch registers. */ - .macro store_primary_cpu_mode reg1, reg2, reg3 + .macro store_primary_cpu_mode reg1, reg2 mrs \reg1, cpsr and \reg1, \reg1, #MODE_MASK - adr \reg2, .L__boot_cpu_mode_offset - ldr \reg3, [\reg2] - str \reg1, [\reg2, \reg3] + str_l \reg1, __boot_cpu_mode, \reg2 .endm
/* * Compare the current mode with the one saved on the primary CPU. * If they don't match, record that fact. The Z bit indicates * if there's a match or not. - * Requires 3 additionnal scratch registers. + * Requires 2 additional scratch registers. */ - .macro compare_cpu_mode_with_primary mode, reg1, reg2, reg3 - adr \reg2, .L__boot_cpu_mode_offset - ldr \reg3, [\reg2] - ldr \reg1, [\reg2, \reg3] + .macro compare_cpu_mode_with_primary mode, reg1, reg2 + adr_l \reg2, __boot_cpu_mode + ldr \reg1, [\reg2] cmp \mode, \reg1 @ matches primary CPU boot mode? orrne \reg1, \reg1, #BOOT_CPU_MODE_MISMATCH - strne \reg1, [\reg2, \reg3] @ record what happened and give up + strne \reg1, [\reg2] @ record what happened and give up .endm
#else /* ZIMAGE */
- .macro store_primary_cpu_mode reg1:req, reg2:req, reg3:req + .macro store_primary_cpu_mode reg1:req, reg2:req .endm
/* * The zImage loader only runs on one CPU, so we don't bother with mult-CPU * consistency checking: */ - .macro compare_cpu_mode_with_primary mode, reg1, reg2, reg3 + .macro compare_cpu_mode_with_primary mode, reg1, reg2 cmp \mode, \mode .endm
@@ -73,7 +70,7 @@ ENTRY(__boot_cpu_mode) */ @ Call this from the primary CPU ENTRY(__hyp_stub_install) - store_primary_cpu_mode r4, r5, r6 + store_primary_cpu_mode r4, r5 ENDPROC(__hyp_stub_install)
@ fall through... @@ -87,7 +84,7 @@ ENTRY(__hyp_stub_install_secondary) * If the secondary has booted with a different mode, give up * immediately. */ - compare_cpu_mode_with_primary r4, r5, r6, r7 + compare_cpu_mode_with_primary r4, r5, r6 retne lr
/*