coreboot/fam15h: only use this, for amd boards

it is identical to fam15h_rdimm, with _udimm now removed;
the latter had a patch that added certain behaviour only
intended for rdimm, but the patch in question breaks various
configurations.

raminit has always been unreliable on these boards. i'd rather
simplify it all, in lbmk. i'll probably update this to the dasharo
tree later on, specificalyl for kgpe-d16

Signed-off-by: Leah Rowe <leah@libreboot.org>

2 files changed, 181 insertions, 0 deletions

diff --git a/config/submodule/coreboot/fam15h/vboot/module.cfg b/config/submodule/coreboot/fam15h/vboot/module.cfg
new file mode 100644
index 00000000..5fac75c3
--- /dev/null
+++ b/config/submodule/coreboot/fam15h/vboot/module.cfg
@@ -0,0 +1,3 @@
+subrepo="https://review.coreboot.org/vboot.git"
+subrepo_bkup="https://github.com/coreboot/vboot"
+subhash="ecdca931ae0637d1a9498f64862939bd5bb99e0b"
diff --git a/config/submodule/coreboot/fam15h/vboot/patches/0001-extract_vmlinuz.c-Fix-the-bounds-check-on-vmlinuz_he.patch b/config/submodule/coreboot/fam15h/vboot/patches/0001-extract_vmlinuz.c-Fix-the-bounds-check-on-vmlinuz_he.patch
new file mode 100644
index 00000000..1ac41de6
--- /dev/null
+++ b/config/submodule/coreboot/fam15h/vboot/patches/0001-extract_vmlinuz.c-Fix-the-bounds-check-on-vmlinuz_he.patch
@@ -0,0 +1,178 @@
+From 195f61375aeec9eec16604ec59f6eda2e6058cc1 Mon Sep 17 00:00:00 2001
+From: "Luke T. Shumaker" <lukeshu@lukeshu.com>
+Date: Thu, 30 May 2024 14:08:33 -0600
+Subject: [PATCH 1/1] extract_vmlinuz.c: Fix the bounds check on
+ vmlinuz_header_{offset,size}
+
+The check on vmlinuz_header_offset and vmlinuz_header_size is obviously
+wrong:
+
+	if (!vmlinuz_header_size ||
+	    kpart_data + vmlinuz_header_offset + vmlinuz_header_size >
+	    kpart_data) {
+		return 1;
+	}
+
+`kpart_data + some_unsigned_values` can obviously never be `> kpart_data`,
+unless something has overflowed!  And `vmlinuz_header_offset` hasn't even
+been set yet (besides being initialized to zero)!
+
+GCC will deduce that if the check didn't cause the function to bail, then
+vmlinuz_header_size (a uint32_t) must be "negative"; that is: in the range
+[2GiB,4GiB).
+
+On platforms where size_t is 32-bits, this is *especially* broken.
+memcpy's size argument must be in the range [0,2GiB).  Because GCC has
+proved that vmlinuz_header_size is higher than that, it will fail to
+compile:
+
+	host/lib/extract_vmlinuz.c:67:9: error: 'memcpy' specified bound between 2147483648 and 4294967295 exceeds maximum object size 2147483647 [-Werror=stringop-overflow=]
+
+So, fix the check.
+
+I can now say that what I suspect the original author meant to write would
+be the following patch, if `vmlinuz_header_offset` were already set:
+
+	-kpart_data + vmlinuz_header_offset + vmlinuz_header_size > kpart_data
+	+now        + vmlinuz_header_offset + vmlinuz_header_size > kpart_size
+
+This hypothesis is supported by `now` not getting incremented by
+`kblob_size` the way it is for the keyblock and preamble sizes.
+
+However, we can also see that even this "corrected" bounds check is
+insufficient: it does not detect the vmlinuz_header overflowing into
+kblob_data.
+
+OK, so let's describe the fix:
+
+Have a `*vmlinuz_header` pointer instead of a
+`uint64_t vmlinuz_header_offset`, to be more similar to all the other
+regions.  With this change, the correct check becomes a simple
+
+      vmlinuz_header + vmlinuz_header_size > kblob_data
+
+While we're at it, make some changes that could have helped avoid this in
+the first place:
+
+ - Add comments.
+ - Calculate the vmlinuz_header offset right away, instead of waiting.
+ - Go ahead and increment `now` by `kblob_size`, to increase regularity.
+
+Change-Id: I5c03e49070b6dd2e04459566ef7dd129d27736e4
+---
+ host/lib/extract_vmlinuz.c | 72 +++++++++++++++++++++++++++-----------
+ 1 file changed, 51 insertions(+), 21 deletions(-)
+
+diff --git a/host/lib/extract_vmlinuz.c b/host/lib/extract_vmlinuz.c
+index 4ccfcf33..d2c09443 100644
+--- a/host/lib/extract_vmlinuz.c
++++ b/host/lib/extract_vmlinuz.c
+@@ -15,16 +15,44 @@
+ 
+ int ExtractVmlinuz(void *kpart_data, size_t kpart_size,
+ 		   void **vmlinuz_out, size_t *vmlinuz_size) {
++	// We're going to be extracting `vmlinuz_header` and
++	// `kblob_data`, and returning the concatenation of them.
++	//
++	// kpart_data = +-[kpart_size]------------------------------------+
++	//              |                                                 |
++	//  keyblock  = | +-[keyblock->keyblock_size]-------------------+ |
++	//              | | struct vb2_keyblock          keyblock       | |
++	//              | | char []                      ...data...     | |
++	//              | +---------------------------------------------+ |
++	//              |                                                 |
++	//  preamble  = | +-[preamble->preamble_size]-------------------+ |
++	//              | | struct vb2_kernel_preamble   preamble       | |
++	//              | | char []                       ...data...    | |
++	//              | | char []                      vmlinuz_header | |
++	//              | | char []                       ...data...    | |
++	//              | +---------------------------------------------+ |
++	//              |                                                 |
++	//  kblob_data= | +-[preamble->body_signature.data_size]--------+ |
++	//              | | char []                       ...data...    | |
++	//              | +---------------------------------------------+ |
++	//              |                                                 |
++	//              +-------------------------------------------------+
++
+ 	size_t now = 0;
++	// The 3 sections of kpart_data.
++	struct vb2_keyblock *keyblock = NULL;
+ 	struct vb2_kernel_preamble *preamble = NULL;
+ 	uint8_t *kblob_data = NULL;
+ 	uint32_t kblob_size = 0;
++	// vmlinuz_header
++	uint8_t *vmlinuz_header = NULL;
+ 	uint32_t vmlinuz_header_size = 0;
+-	uint64_t vmlinuz_header_address = 0;
+-	uint64_t vmlinuz_header_offset = 0;
++	// The concatenated result.
+ 	void *vmlinuz = NULL;
+ 
+-	struct vb2_keyblock *keyblock = (struct vb2_keyblock *)kpart_data;
++	// Isolate the 3 sections of kpart_data.
++
++	keyblock = (struct vb2_keyblock *)kpart_data;
+ 	now += keyblock->keyblock_size;
+ 	if (now > kpart_size)
+ 		return 1;
+@@ -36,37 +64,39 @@ int ExtractVmlinuz(void *kpart_data, size_t kpart_size,
+ 
+ 	kblob_data = kpart_data + now;
+ 	kblob_size = preamble->body_signature.data_size;
+-
+-	if (!kblob_data || (now + kblob_size) > kpart_size)
++	now += kblob_size;
++	if (now > kpart_size)
+ 		return 1;
+ 
++	// Find `vmlinuz_header` within `preamble`.
++
+ 	if (preamble->header_version_minor > 0) {
+-		vmlinuz_header_address = preamble->vmlinuz_header_address;
++		// calculate the vmlinuz_header offset from
++		// the beginning of the kpart_data.  The kblob doesn't
++		// include the body_load_offset, but does include
++		// the keyblock and preamble sections.
++		size_t vmlinuz_header_offset =
++			preamble->vmlinuz_header_address -
++			preamble->body_load_address +
++			keyblock->keyblock_size +
++			preamble->preamble_size;
++
++		vmlinuz_header = kpart_data + vmlinuz_header_offset;
+ 		vmlinuz_header_size = preamble->vmlinuz_header_size;
+ 	}
+ 
+-	if (!vmlinuz_header_size ||
+-	    kpart_data + vmlinuz_header_offset + vmlinuz_header_size >
+-	    kpart_data) {
++	if (!vmlinuz_header ||
++	    !vmlinuz_header_size ||
++	    vmlinuz_header + vmlinuz_header_size > kblob_data) {
+ 		return 1;
+ 	}
+ 
+-	// calculate the vmlinuz_header offset from
+-	// the beginning of the kpart_data.  The kblob doesn't
+-	// include the body_load_offset, but does include
+-	// the keyblock and preamble sections.
+-	vmlinuz_header_offset = vmlinuz_header_address -
+-		preamble->body_load_address +
+-		keyblock->keyblock_size +
+-		preamble->preamble_size;
++	// Concatenate and return.
+ 
+ 	vmlinuz = malloc(vmlinuz_header_size + kblob_size);
+ 	if (vmlinuz == NULL)
+ 		return 1;
+-
+-	memcpy(vmlinuz, kpart_data + vmlinuz_header_offset,
+-	       vmlinuz_header_size);
+-
++	memcpy(vmlinuz, vmlinuz_header, vmlinuz_header_size);
+ 	memcpy(vmlinuz + vmlinuz_header_size, kblob_data, kblob_size);
+ 
+ 	*vmlinuz_out = vmlinuz;
+-- 
+2.45.1
+