x86/bugs: Some SRSO fixes

[PATCH 2/3] driver core: cpu: Unify redundant silly stubs

Posted by Borislav Petkov 2 years, 1 month ago

From: "Borislav Petkov (AMD)" <bp@alien8.de>

Make them all a weak function, aliasing to a single function which
issues the "Not affected" string.

No functional changes.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
---
 drivers/base/cpu.c | 86 ++++++++++------------------------------------
 1 file changed, 18 insertions(+), 68 deletions(-)

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 52df435eecf8..971771347aa6 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -509,79 +509,29 @@ static void __init cpu_dev_register_generic(void)
 }
 
 #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES
-
-ssize_t __weak cpu_show_meltdown(struct device *dev,
-				 struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spectre_v1(struct device *dev,
-				   struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spectre_v2(struct device *dev,
-				   struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spec_store_bypass(struct device *dev,
-					  struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_l1tf(struct device *dev,
-			     struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_mds(struct device *dev,
-			    struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_tsx_async_abort(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
-				      struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_srbds(struct device *dev,
+ssize_t cpu_show_not_affected(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
 	return sysfs_emit(buf, "Not affected\n");
 }
 
-ssize_t __weak cpu_show_mmio_stale_data(struct device *dev,
-					struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_retbleed(struct device *dev,
-				 struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spec_rstack_overflow(struct device *dev,
-					     struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
+#define CPU_VULN_FALLBACK(func)						\
+	ssize_t cpu_show_##func(struct device *,			\
+				  struct device_attribute *, char *)	\
+		 __attribute__((weak, alias("cpu_show_not_affected")))
+
+CPU_VULN_FALLBACK(meltdown);
+CPU_VULN_FALLBACK(spectre_v1);
+CPU_VULN_FALLBACK(spectre_v2);
+CPU_VULN_FALLBACK(spec_store_bypass);
+CPU_VULN_FALLBACK(l1tf);
+CPU_VULN_FALLBACK(mds);
+CPU_VULN_FALLBACK(tsx_async_abort);
+CPU_VULN_FALLBACK(itlb_multihit);
+CPU_VULN_FALLBACK(srbds);
+CPU_VULN_FALLBACK(mmio_stale_data);
+CPU_VULN_FALLBACK(retbleed);
+CPU_VULN_FALLBACK(spec_rstack_overflow);
 
 ssize_t __weak cpu_show_gds(struct device *dev,
 			    struct device_attribute *attr, char *buf)
-- 
2.41.0

Re: [PATCH 2/3] driver core: cpu: Unify redundant silly stubs

Posted by Pawan Gupta 2 years, 1 month ago

On Wed, Aug 09, 2023 at 12:26:59PM +0200, Borislav Petkov wrote:
> From: "Borislav Petkov (AMD)" <bp@alien8.de>
> 
> Make them all a weak function, aliasing to a single function which
> issues the "Not affected" string.
> 
> No functional changes.
> 
> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
> ---
>  drivers/base/cpu.c | 86 ++++++++++------------------------------------
>  1 file changed, 18 insertions(+), 68 deletions(-)
> 
> diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
> index 52df435eecf8..971771347aa6 100644
> --- a/drivers/base/cpu.c
> +++ b/drivers/base/cpu.c
> @@ -509,79 +509,29 @@ static void __init cpu_dev_register_generic(void)
>  }
>  
>  #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES
> -
> -ssize_t __weak cpu_show_meltdown(struct device *dev,
> -				 struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_spectre_v1(struct device *dev,
> -				   struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_spectre_v2(struct device *dev,
> -				   struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_spec_store_bypass(struct device *dev,
> -					  struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_l1tf(struct device *dev,
> -			     struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_mds(struct device *dev,
> -			    struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_tsx_async_abort(struct device *dev,
> -					struct device_attribute *attr,
> -					char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
> -				      struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_srbds(struct device *dev,
> +ssize_t cpu_show_not_affected(struct device *dev,
>  			      struct device_attribute *attr, char *buf)
>  {
>  	return sysfs_emit(buf, "Not affected\n");
>  }
>  
> -ssize_t __weak cpu_show_mmio_stale_data(struct device *dev,
> -					struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_retbleed(struct device *dev,
> -				 struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> -
> -ssize_t __weak cpu_show_spec_rstack_overflow(struct device *dev,
> -					     struct device_attribute *attr, char *buf)
> -{
> -	return sysfs_emit(buf, "Not affected\n");
> -}
> +#define CPU_VULN_FALLBACK(func)						\

Nit, its not actually a vulnerability fallback, does
CPU_SHOW_VULN_FALLBACK() sound better?

> +	ssize_t cpu_show_##func(struct device *,			\
> +				  struct device_attribute *, char *)	\
> +		 __attribute__((weak, alias("cpu_show_not_affected")))
> +
> +CPU_VULN_FALLBACK(meltdown);
> +CPU_VULN_FALLBACK(spectre_v1);
> +CPU_VULN_FALLBACK(spectre_v2);
> +CPU_VULN_FALLBACK(spec_store_bypass);
> +CPU_VULN_FALLBACK(l1tf);
> +CPU_VULN_FALLBACK(mds);
> +CPU_VULN_FALLBACK(tsx_async_abort);
> +CPU_VULN_FALLBACK(itlb_multihit);
> +CPU_VULN_FALLBACK(srbds);
> +CPU_VULN_FALLBACK(mmio_stale_data);
> +CPU_VULN_FALLBACK(retbleed);
> +CPU_VULN_FALLBACK(spec_rstack_overflow);
>  
>  ssize_t __weak cpu_show_gds(struct device *dev,
>  			    struct device_attribute *attr, char *buf)

Do you want me to send a separate patch for this?

Re: [PATCH 2/3] driver core: cpu: Unify redundant silly stubs

Posted by Borislav Petkov 2 years, 1 month ago

On Wed, Aug 09, 2023 at 02:47:41PM -0700, Pawan Gupta wrote:
> Do you want me to send a separate patch for this?

No need - I'll fix it up.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH 2/3] driver core: cpu: Unify redundant silly stubs

Posted by Nikolay Borisov 2 years, 1 month ago


On 9.08.23 г. 13:26 ч., Borislav Petkov wrote:
> From: "Borislav Petkov (AMD)" <bp@alien8.de>
> 
> Make them all a weak function, aliasing to a single function which
> issues the "Not affected" string.
> 
> No functional changes.
> 
> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>


Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>

[tip: x86/bugs] driver core: cpu: Unify redundant silly stubs

Posted by tip-bot2 for Borislav Petkov (AMD) 2 years, 1 month ago

The following commit has been merged into the x86/bugs branch of tip:

Commit-ID:     0fddfe338210aa018137c03030c581f5ea4be282
Gitweb:        https://git.kernel.org/tip/0fddfe338210aa018137c03030c581f5ea4be282
Author:        Borislav Petkov (AMD) <bp@alien8.de>
AuthorDate:    Sat, 29 Jul 2023 17:20:33 +02:00
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Thu, 10 Aug 2023 11:03:04 +02:00

driver core: cpu: Unify redundant silly stubs

Make them all a weak function, aliasing to a single function which
issues the "Not affected" string.

No functional changes.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Link: https://lore.kernel.org/r/20230809102700.29449-3-bp@alien8.de
---
 drivers/base/cpu.c | 87 +++++++++------------------------------------
 1 file changed, 19 insertions(+), 68 deletions(-)

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 52df435..054c81b 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -509,79 +509,30 @@ static void __init cpu_dev_register_generic(void)
 }
 
 #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES
-
-ssize_t __weak cpu_show_meltdown(struct device *dev,
-				 struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spectre_v1(struct device *dev,
-				   struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spectre_v2(struct device *dev,
-				   struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spec_store_bypass(struct device *dev,
-					  struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_l1tf(struct device *dev,
-			     struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_mds(struct device *dev,
-			    struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_tsx_async_abort(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
-				      struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_srbds(struct device *dev,
+ssize_t cpu_show_not_affected(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
 	return sysfs_emit(buf, "Not affected\n");
 }
 
-ssize_t __weak cpu_show_mmio_stale_data(struct device *dev,
-					struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_retbleed(struct device *dev,
-				 struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
-
-ssize_t __weak cpu_show_spec_rstack_overflow(struct device *dev,
-					     struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "Not affected\n");
-}
+#define CPU_SHOW_VULN_FALLBACK(func)					\
+	ssize_t cpu_show_##func(struct device *,			\
+				  struct device_attribute *, char *)	\
+		 __attribute__((weak, alias("cpu_show_not_affected")))
+
+CPU_SHOW_VULN_FALLBACK(meltdown);
+CPU_SHOW_VULN_FALLBACK(spectre_v1);
+CPU_SHOW_VULN_FALLBACK(spectre_v2);
+CPU_SHOW_VULN_FALLBACK(spec_store_bypass);
+CPU_SHOW_VULN_FALLBACK(l1tf);
+CPU_SHOW_VULN_FALLBACK(mds);
+CPU_SHOW_VULN_FALLBACK(tsx_async_abort);
+CPU_SHOW_VULN_FALLBACK(itlb_multihit);
+CPU_SHOW_VULN_FALLBACK(srbds);
+CPU_SHOW_VULN_FALLBACK(mmio_stale_data);
+CPU_SHOW_VULN_FALLBACK(retbleed);
+CPU_SHOW_VULN_FALLBACK(spec_rstack_overflow);
+CPU_SHOW_VULN_FALLBACK(gather_data_sampling);
 
 ssize_t __weak cpu_show_gds(struct device *dev,
 			    struct device_attribute *attr, char *buf)