[GIT PULL] EFI fix

[GIT PULL] EFI fix

[Ingo Molnar]

Linus,

Please pull the latest efi-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus

   # HEAD: 792ef14df5c585c19b2831673a077504a09e5203 efi: Fix boot panic because of invalid BGRT image address

A boot crash fix for certain systems where the kernel would trust a piece of 
firmware data it should not have.

 Thanks,

	Ingo

------------------>
Dave Young (1):
      efi: Fix boot panic because of invalid BGRT image address


 drivers/firmware/efi/efi-bgrt.c | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/efi-bgrt.c b/drivers/firmware/efi/efi-bgrt.c
index 8bf27323f7a3..b58233e4ed71 100644
--- a/drivers/firmware/efi/efi-bgrt.c
+++ b/drivers/firmware/efi/efi-bgrt.c
@@ -27,6 +27,26 @@ struct bmp_header {
 	u32 size;
 } __packed;
 
+static bool efi_bgrt_addr_valid(u64 addr)
+{
+	efi_memory_desc_t *md;
+
+	for_each_efi_memory_desc(md) {
+		u64 size;
+		u64 end;
+
+		if (md->type != EFI_BOOT_SERVICES_DATA)
+			continue;
+
+		size = md->num_pages << EFI_PAGE_SHIFT;
+		end = md->phys_addr + size;
+		if (addr >= md->phys_addr && addr < end)
+			return true;
+	}
+
+	return false;
+}
+
 void __init efi_bgrt_init(struct acpi_table_header *table)
 {
 	void *image;
@@ -36,7 +56,7 @@ void __init efi_bgrt_init(struct acpi_table_header *table)
 	if (acpi_disabled)
 		return;
 
-	if (!efi_enabled(EFI_BOOT))
+	if (!efi_enabled(EFI_MEMMAP))
 		return;
 
 	if (table->length < sizeof(bgrt_tab)) {
@@ -65,6 +85,10 @@ void __init efi_bgrt_init(struct acpi_table_header *table)
 		goto out;
 	}
 
+	if (!efi_bgrt_addr_valid(bgrt->image_address)) {
+		pr_notice("Ignoring BGRT: invalid image address\n");
+		goto out;
+	}
 	image = early_memremap(bgrt->image_address, sizeof(bmp_header));
 	if (!image) {
 		pr_notice("Ignoring BGRT: failed to map image header memory\n");

Re: [GIT PULL] EFI fix

[Ingo Molnar]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Thu, Jan 10, 2019 at 11:46 PM Ingo Molnar <mingo@kernel.org> wrote:
> >
> > A single fix that adds an annotation to resolve a kmemleak false
> > positive.
> 
> This one is apparently obviated by commit 80424b02d42b ("efi: Reduce
> the amount of memblock reservations for persistent allocations")

... and it turns out I mis-merged it in tip:master not realizing this 
connection (hence the pull request) - so good thing that Ard warned about 
this and you double checked it!

Thanks,

	Ingo

Re: [GIT PULL] EFI fix

[Ingo Molnar]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Fri, Jan 11, 2019 at 6:22 AM Ard Biesheuvel
> <ard.biesheuvel@linaro.org> wrote:
> >
> > I was hoping we could merge this patch (so we can backport it), but
> > resolve the conflict by dropping the kmemleak_ignore() again [..]
> 
> Well, we'd drop the new #include line also, since it would be
> pointless without the kmemleak_ignore().
> 
> End result: there would be nothing left. Better not to merge it at all.

Indeed!

> It's easy enough to backport, and just say "done differently upstream
> in commit 80424b02d42b ("efi: Reduce the amount of memblock
> reservations for persistent allocations").
> 
> The stable tree doesn't require that the *same* commits be upstream,
> it only requires that the fixes be upstream and Greg&al want a pointer
> to the upstream fix just so that they know they're not fixing
> something that might still be broken upstream.
> 
> See for example (just random googling)
> 
>    https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=37435f7e80ef9adc32a69013c18f135e3f434244
> 
> which shows that "fixed differently upstream" case and points to why.

Thanks - I'm dropping the commit from efi/urgent.

	Ingo

Re: [GIT PULL] EFI fix

[Linus Torvalds]

On Fri, Jan 11, 2019 at 6:22 AM Ard Biesheuvel
<ard.biesheuvel@linaro.org> wrote:
>
> I was hoping we could merge this patch (so we can backport it), but
> resolve the conflict by dropping the kmemleak_ignore() again [..]

Well, we'd drop the new #include line also, since it would be
pointless without the kmemleak_ignore().

End result: there would be nothing left. Better not to merge it at all.

It's easy enough to backport, and just say "done differently upstream
in commit 80424b02d42b ("efi: Reduce the amount of memblock
reservations for persistent allocations").

The stable tree doesn't require that the *same* commits be upstream,
it only requires that the fixes be upstream and Greg&al want a pointer
to the upstream fix just so that they know they're not fixing
something that might still be broken upstream.

See for example (just random googling)

   https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=37435f7e80ef9adc32a69013c18f135e3f434244

which shows that "fixed differently upstream" case and points to why.

                  Linus

Re: [GIT PULL] EFI fix

[Linus Torvalds]

On Thu, Jan 10, 2019 at 11:46 PM Ingo Molnar <mingo@kernel.org> wrote:
>
> A single fix that adds an annotation to resolve a kmemleak false
> positive.

This one is apparently obviated by commit 80424b02d42b ("efi: Reduce
the amount of memblock reservations for persistent allocations")

               Linus

Re: [GIT PULL] EFI fix

[Ard Biesheuvel]

On Fri, 11 Jan 2019 at 08:46, Ingo Molnar <mingo@kernel.org> wrote:
>
> Linus,
>
> Please pull the latest efi-urgent-for-linus git tree from:
>
>    git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus
>
>    # HEAD: b12f5440d8ca02e8f9ab4f1461f9214295cc4f66 Merge branch 'linus' into efi/urgent, to resolve conflict
>
> A single fix that adds an annotation to resolve a kmemleak false
> positive.
>
>  Thanks,
>
>         Ingo
>
> ------------------>
> Qian Cai (1):
>       efi: Let kmemleak ignore false positives
>
>
>  drivers/firmware/efi/efi.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
> index 4c46ff6f2242..7ac09dd8f268 100644
> --- a/drivers/firmware/efi/efi.c
> +++ b/drivers/firmware/efi/efi.c
> @@ -31,6 +31,7 @@
>  #include <linux/acpi.h>
>  #include <linux/ucs2_string.h>
>  #include <linux/memblock.h>
> +#include <linux/kmemleak.h>
>
>  #include <asm/early_ioremap.h>
>
> @@ -1026,6 +1027,8 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
>         if (!rsv)
>                 return -ENOMEM;
>
> +       kmemleak_ignore(rsv);
> +
>         rsv->size = EFI_MEMRESERVE_COUNT(PAGE_SIZE);
>         atomic_set(&rsv->count, 1);
>         rsv->entry[0].base = addr;

I was hoping we could merge this patch (so we can backport it), but
resolve the conflict by dropping the kmemleak_ignore() again, since it
will now complain since the kmalloc() has been replaced with a
__get_free_page() in the mean time (if that makes sense)

[GIT PULL] EFI fix

[Ingo Molnar]

Linus,

Please pull the latest efi-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus

   # HEAD: b12f5440d8ca02e8f9ab4f1461f9214295cc4f66 Merge branch 'linus' into efi/urgent, to resolve conflict

A single fix that adds an annotation to resolve a kmemleak false 
positive.

 Thanks,

	Ingo

------------------>
Qian Cai (1):
      efi: Let kmemleak ignore false positives


 drivers/firmware/efi/efi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 4c46ff6f2242..7ac09dd8f268 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -31,6 +31,7 @@
 #include <linux/acpi.h>
 #include <linux/ucs2_string.h>
 #include <linux/memblock.h>
+#include <linux/kmemleak.h>
 
 #include <asm/early_ioremap.h>
 
@@ -1026,6 +1027,8 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
 	if (!rsv)
 		return -ENOMEM;
 
+	kmemleak_ignore(rsv);
+
 	rsv->size = EFI_MEMRESERVE_COUNT(PAGE_SIZE);
 	atomic_set(&rsv->count, 1);
 	rsv->entry[0].base = addr;

[GIT PULL] EFI fix

[Ingo Molnar]

Linus,

Please pull the latest efi-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus

   # HEAD: 9b788f32bee6b0b293a4bdfca4ad4bb0206407fb x86/efi: Access EFI MMIO data as unencrypted when SEV is active

An UEFI variables fix for SEV guests.

 Thanks,

	Ingo

------------------>
Brijesh Singh (1):
      x86/efi: Access EFI MMIO data as unencrypted when SEV is active


 arch/x86/platform/efi/efi_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 77873ce700ae..5f2eb3231607 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -417,7 +417,7 @@ static void __init __map_region(efi_memory_desc_t *md, u64 va)
 	if (!(md->attribute & EFI_MEMORY_WB))
 		flags |= _PAGE_PCD;
 
-	if (sev_active())
+	if (sev_active() && md->type != EFI_MEMORY_MAPPED_IO)
 		flags |= _PAGE_ENC;
 
 	pfn = md->phys_addr >> PAGE_SHIFT;