summaryrefslogtreecommitdiffstats
path: root/arch/x86/entry
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 18:43:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 18:43:27 +0000
commit2923512cee3cfb8eaf935324ddc8f6edd8263e93 (patch)
tree2cfe4d9883ebfd5ecede5f13892ee2d6e14c486e /arch/x86/entry
parentAdding upstream version 6.7.7. (diff)
downloadlinux-2923512cee3cfb8eaf935324ddc8f6edd8263e93.tar.xz
linux-2923512cee3cfb8eaf935324ddc8f6edd8263e93.zip
Adding upstream version 6.7.9.upstream/6.7.9
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/entry')
-rw-r--r--arch/x86/entry/entry_32.S3
-rw-r--r--arch/x86/entry/entry_64.S11
-rw-r--r--arch/x86/entry/entry_64_compat.S1
3 files changed, 15 insertions, 0 deletions
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index c73047bf9f..fba4276468 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -885,6 +885,7 @@ SYM_FUNC_START(entry_SYSENTER_32)
BUG_IF_WRONG_CR3 no_user_check=1
popfl
popl %eax
+ CLEAR_CPU_BUFFERS
/*
* Return back to the vDSO, which will pop ecx and edx.
@@ -954,6 +955,7 @@ restore_all_switch_stack:
/* Restore user state */
RESTORE_REGS pop=4 # skip orig_eax/error_code
+ CLEAR_CPU_BUFFERS
.Lirq_return:
/*
* ARCH_HAS_MEMBARRIER_SYNC_CORE rely on IRET core serialization
@@ -1146,6 +1148,7 @@ SYM_CODE_START(asm_exc_nmi)
/* Not on SYSENTER stack. */
call exc_nmi
+ CLEAR_CPU_BUFFERS
jmp .Lnmi_return
.Lnmi_from_sysenter_stack:
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index de6469dffe..bdb17fad5d 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -161,6 +161,7 @@ syscall_return_via_sysret:
SYM_INNER_LABEL(entry_SYSRETQ_unsafe_stack, SYM_L_GLOBAL)
ANNOTATE_NOENDBR
swapgs
+ CLEAR_CPU_BUFFERS
sysretq
SYM_INNER_LABEL(entry_SYSRETQ_end, SYM_L_GLOBAL)
ANNOTATE_NOENDBR
@@ -601,6 +602,7 @@ SYM_INNER_LABEL(swapgs_restore_regs_and_return_to_usermode, SYM_L_GLOBAL)
/* Restore RDI. */
popq %rdi
swapgs
+ CLEAR_CPU_BUFFERS
jmp .Lnative_iret
@@ -712,6 +714,8 @@ native_irq_return_ldt:
*/
popq %rax /* Restore user RAX */
+ CLEAR_CPU_BUFFERS
+
/*
* RSP now points to an ordinary IRET frame, except that the page
* is read-only and RSP[31:16] are preloaded with the userspace
@@ -1439,6 +1443,12 @@ nmi_restore:
movq $0, 5*8(%rsp) /* clear "NMI executing" */
/*
+ * Skip CLEAR_CPU_BUFFERS here, since it only helps in rare cases like
+ * NMI in kernel after user state is restored. For an unprivileged user
+ * these conditions are hard to meet.
+ */
+
+ /*
* iretq reads the "iret" frame and exits the NMI stack in a
* single instruction. We are returning to kernel mode, so this
* cannot result in a fault. Similarly, we don't need to worry
@@ -1455,6 +1465,7 @@ SYM_CODE_START(entry_SYSCALL32_ignore)
UNWIND_HINT_END_OF_STACK
ENDBR
mov $-ENOSYS, %eax
+ CLEAR_CPU_BUFFERS
sysretl
SYM_CODE_END(entry_SYSCALL32_ignore)
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index de94e2e84e..eabf48c4d4 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -270,6 +270,7 @@ SYM_INNER_LABEL(entry_SYSRETL_compat_unsafe_stack, SYM_L_GLOBAL)
xorl %r9d, %r9d
xorl %r10d, %r10d
swapgs
+ CLEAR_CPU_BUFFERS
sysretl
SYM_INNER_LABEL(entry_SYSRETL_compat_end, SYM_L_GLOBAL)
ANNOTATE_NOENDBR