jchzhou/kernel-sophgo-sg2044-revyos-6.17-src
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/bugs: Fix reporting of LFENCE retpoline

Browse Source 
[ Upstream commit d1cc1baef67ac6c09b74629ca053bf3fb812f7dc ]

The LFENCE retpoline mitigation is not secure but the kernel prints
inconsistent messages about this fact.  The dmesg log says 'Mitigation:
LFENCE', implying the system is mitigated.  But sysfs reports 'Vulnerable:
LFENCE' implying the system (correctly) is not mitigated.

Fix this by printing a consistent 'Vulnerable: LFENCE' string everywhere
when this mitigation is selected.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250915134706.3201818-1-david.kaplan@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
David Kaplan
2025-09-15 08:47:05 -05:00
committed by Greg Kroah-Hartman
parent 28621b2b0a
commit 6561a5b4e3
1 changed files with 1 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
arch/x86/kernel/cpu/bugs.c
View File

@@ -2052,7 +2052,7 @@ static void __init spectre_v2_user_apply_mitigation(void)
static const char * const spectre_v2_strings[] = {
[SPECTRE_V2_NONE] = "Vulnerable",
[SPECTRE_V2_RETPOLINE] = "Mitigation: Retpolines",
[SPECTRE_V2_LFENCE] = "Mitigation: LFENCE",
[SPECTRE_V2_LFENCE] = "Vulnerable: LFENCE",
[SPECTRE_V2_EIBRS] = "Mitigation: Enhanced / Automatic IBRS",
[SPECTRE_V2_EIBRS_LFENCE] = "Mitigation: Enhanced / Automatic IBRS + LFENCE",
[SPECTRE_V2_EIBRS_RETPOLINE] = "Mitigation: Enhanced / Automatic IBRS + Retpolines",
@@ -3636,9 +3636,6 @@ static const char *spectre_bhi_state(void)
static ssize_t spectre_v2_show_state(char *buf)
{
if (spectre_v2_enabled == SPECTRE_V2_LFENCE)
return sysfs_emit(buf, "Vulnerable: LFENCE\n");
if (spectre_v2_enabled == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
return sysfs_emit(buf, "Vulnerable: eIBRS with unprivileged eBPF\n");