diff mbox series

[livepatch-build-tools:,independ.,modules] livepatch-build: Embed hypervisor build id into every hotpatch

Message ID 20190416125714.32771-1-wipawel@amazon.de (mailing list archive)
State New, archived
Headers show
Series [livepatch-build-tools:,independ.,modules] livepatch-build: Embed hypervisor build id into every hotpatch | expand

Commit Message

Wieczorkiewicz, Pawel April 16, 2019, 12:57 p.m. UTC
This change is part of a independant stacked hotpatch modules
feature. This feature allows to bypass dependencies between modules
upon loading, but still verifies Xen build ID matching.

With stacked hotpatch modules it is essential that each and every
hotpatch is verified against the hypervisor build id upon upload.
It must not be possible to successfully upload hotpatches built for
incorrect version of the hypervisor.

To achieve that always embed an additional ELF section:
'.livpatch.xen_depends' containing the hypervisor build id.

The hypervisor build id must be always provided as a command line
parameter: --xen-depends.

Signed-off-by: Pawel Wieczorkiewicz <wipawel@amazon.de>
Reviewed-by: Andra-Irina Paraschiv <andraprs@amazon.com>
Reviewed-by: Bjoern Doebel <doebel@amazon.de>
Reviewed-by: Norbert Manthey <nmanthey@amazon.de>
---
 livepatch-build | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

Comments

Konrad Rzeszutek Wilk April 25, 2019, 4:49 a.m. UTC | #1
On Tue, Apr 16, 2019 at 12:57:14PM +0000, Pawel Wieczorkiewicz wrote:
> This change is part of a independant stacked hotpatch modules
> feature. This feature allows to bypass dependencies between modules
> upon loading, but still verifies Xen build ID matching.
> 
> With stacked hotpatch modules it is essential that each and every
> hotpatch is verified against the hypervisor build id upon upload.
> It must not be possible to successfully upload hotpatches built for
> incorrect version of the hypervisor.
> 
> To achieve that always embed an additional ELF section:
> '.livpatch.xen_depends' containing the hypervisor build id.
> 
> The hypervisor build id must be always provided as a command line
> parameter: --xen-depends.
> 
> Signed-off-by: Pawel Wieczorkiewicz <wipawel@amazon.de>
> Reviewed-by: Andra-Irina Paraschiv <andraprs@amazon.com>
> Reviewed-by: Bjoern Doebel <doebel@amazon.de>
> Reviewed-by: Norbert Manthey <nmanthey@amazon.de>

This patch looks OK, but I would want to wait until the Xen hypervisor
one gets the test-cases+documentation changes..

> ---
>  livepatch-build | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/livepatch-build b/livepatch-build
> index c057fa1..0938b3a 100755
> --- a/livepatch-build
> +++ b/livepatch-build
> @@ -30,6 +30,7 @@ DEBUG=n
>  XEN_DEBUG=n
>  SKIP=
>  DEPENDS=
> +XEN_DEPENDS=
>  PRELINK=
>  XENSYMS=xen-syms
>  
> @@ -157,6 +158,9 @@ function create_patch()
>      # Create a dependency section
>      perl -e "print pack 'VVVZ*H*', 4, 20, 3, 'GNU', '${DEPENDS}'" > depends.bin
>  
> +    # Create a Xen dependency section
> +    perl -e "print pack 'VVVZ*H*', 4, 20, 3, 'GNU', '${XEN_DEPENDS}'" > xen_depends.bin
> +
>      echo "Creating patch module..."
>      if [ -z "$PRELINK" ]; then
>          ld -r -o "${PATCHNAME}.livepatch" --build-id=sha1 $(find output -type f -name "*.o") || die
> @@ -168,6 +172,9 @@ function create_patch()
>  
>      objcopy --add-section .livepatch.depends=depends.bin "${PATCHNAME}.livepatch"
>      objcopy --set-section-flags .livepatch.depends=alloc,readonly "${PATCHNAME}.livepatch"
> +
> +    objcopy --add-section .livepatch.xen_depends=xen_depends.bin "${PATCHNAME}.livepatch"
> +    objcopy --set-section-flags .livepatch.xen_depends=alloc,readonly "${PATCHNAME}.livepatch"
>  }
>  
>  usage() {
> @@ -183,12 +190,13 @@ usage() {
>      echo "        --xen-debug        Build debug Xen (if your .config does not have the options)" >&2
>      echo "        --xen-syms         Build against a xen-syms" >&2
>      echo "        --depends          Required build-id" >&2
> +    echo "        --xen-depends      Required Xen build-id" >&2
>      echo "        --prelink          Prelink" >&2
>  }
>  
>  find_tools || die "can't find supporting tools"
>  
> -options=$(getopt -o hs:p:c:o:j:k:d -l "help,srcdir:,patch:,config:,output:,cpus:,skip:,debug,xen-debug,xen-syms:,depends:,prelink" -- "$@") || die "getopt failed"
> +options=$(getopt -o hs:p:c:o:j:k:d -l "help,srcdir:,patch:,config:,output:,cpus:,skip:,debug,xen-debug,xen-syms:,depends:,xen-depends:,prelink" -- "$@") || die "getopt failed"
>  
>  eval set -- "$options"
>  
> @@ -247,6 +255,11 @@ while [[ $# -gt 0 ]]; do
>              DEPENDS="$1"
>              shift
>              ;;
> +        --xen-depends)
> +            shift
> +            XEN_DEPENDS="$1"
> +            shift
> +            ;;
>          --prelink)
>              PRELINK=--resolve
>              shift
> @@ -263,6 +276,7 @@ done
>  [ -z "$configarg" ] && die ".config not given"
>  [ -z "$outputarg" ] && die "Output directory not given"
>  [ -z "$DEPENDS" ] && die "Build-id dependency not given"
> +[ -z "$XEN_DEPENDS" ] && die "Xen Build-id dependency not given"
>  
>  SRCDIR="$(readlink -m -- "$srcarg")"
>  PATCHFILE="$(readlink -m -- "$patcharg")"
> -- 
> 2.16.5
> 
> 
> 
> 
> Amazon Development Center Germany GmbH
> Krausenstr. 38
> 10117 Berlin
> Geschaeftsfuehrer: Christian Schlaeger, Ralf Herbrich
> Ust-ID: DE 289 237 879
> Eingetragen am Amtsgericht Charlottenburg HRB 149173 B
> 
>
diff mbox series

Patch

diff --git a/livepatch-build b/livepatch-build
index c057fa1..0938b3a 100755
--- a/livepatch-build
+++ b/livepatch-build
@@ -30,6 +30,7 @@  DEBUG=n
 XEN_DEBUG=n
 SKIP=
 DEPENDS=
+XEN_DEPENDS=
 PRELINK=
 XENSYMS=xen-syms
 
@@ -157,6 +158,9 @@  function create_patch()
     # Create a dependency section
     perl -e "print pack 'VVVZ*H*', 4, 20, 3, 'GNU', '${DEPENDS}'" > depends.bin
 
+    # Create a Xen dependency section
+    perl -e "print pack 'VVVZ*H*', 4, 20, 3, 'GNU', '${XEN_DEPENDS}'" > xen_depends.bin
+
     echo "Creating patch module..."
     if [ -z "$PRELINK" ]; then
         ld -r -o "${PATCHNAME}.livepatch" --build-id=sha1 $(find output -type f -name "*.o") || die
@@ -168,6 +172,9 @@  function create_patch()
 
     objcopy --add-section .livepatch.depends=depends.bin "${PATCHNAME}.livepatch"
     objcopy --set-section-flags .livepatch.depends=alloc,readonly "${PATCHNAME}.livepatch"
+
+    objcopy --add-section .livepatch.xen_depends=xen_depends.bin "${PATCHNAME}.livepatch"
+    objcopy --set-section-flags .livepatch.xen_depends=alloc,readonly "${PATCHNAME}.livepatch"
 }
 
 usage() {
@@ -183,12 +190,13 @@  usage() {
     echo "        --xen-debug        Build debug Xen (if your .config does not have the options)" >&2
     echo "        --xen-syms         Build against a xen-syms" >&2
     echo "        --depends          Required build-id" >&2
+    echo "        --xen-depends      Required Xen build-id" >&2
     echo "        --prelink          Prelink" >&2
 }
 
 find_tools || die "can't find supporting tools"
 
-options=$(getopt -o hs:p:c:o:j:k:d -l "help,srcdir:,patch:,config:,output:,cpus:,skip:,debug,xen-debug,xen-syms:,depends:,prelink" -- "$@") || die "getopt failed"
+options=$(getopt -o hs:p:c:o:j:k:d -l "help,srcdir:,patch:,config:,output:,cpus:,skip:,debug,xen-debug,xen-syms:,depends:,xen-depends:,prelink" -- "$@") || die "getopt failed"
 
 eval set -- "$options"
 
@@ -247,6 +255,11 @@  while [[ $# -gt 0 ]]; do
             DEPENDS="$1"
             shift
             ;;
+        --xen-depends)
+            shift
+            XEN_DEPENDS="$1"
+            shift
+            ;;
         --prelink)
             PRELINK=--resolve
             shift
@@ -263,6 +276,7 @@  done
 [ -z "$configarg" ] && die ".config not given"
 [ -z "$outputarg" ] && die "Output directory not given"
 [ -z "$DEPENDS" ] && die "Build-id dependency not given"
+[ -z "$XEN_DEPENDS" ] && die "Xen Build-id dependency not given"
 
 SRCDIR="$(readlink -m -- "$srcarg")"
 PATCHFILE="$(readlink -m -- "$patcharg")"