Merge pull request #788 from danielinux/fenrir-fixes-2026-06-05

Fenrir fixes 2026 06 05

Author: mattia-moffa

.gitignore

@@ -188,6 +188,8 @@ tools/unit-tests/unit-max-space
 tools/unit-tests/unit-sdhci-disk-unaligned
 tools/unit-tests/unit-fwtpm-stub
 tools/unit-tests/unit-gzip
+tools/unit-tests/unit-linux-loader-e820
+tools/unit-tests/unit-linux-loader-syssize
 
 
 # Elf preprocessing tools

src/arm_tee_psa_ipc.c

@@ -766,16 +766,23 @@ int32_t arm_tee_psa_call(psa_handle_t handle, int32_t type,
             const void *data;
             const psa_storage_create_flags_t *flags;
             struct wolfboot_ps_entry *entry;
+            size_t data_len;
             if (in_vec == NULL || in_len < 3) {
                 return PSA_ERROR_INVALID_ARGUMENT;
             }
             uid = (const psa_storage_uid_t *)in_vec[0].base;
             data = in_vec[1].base;
             flags = (const psa_storage_create_flags_t *)in_vec[2].base;
+            /* Snapshot the NS-supplied length once into a Secure-stack local.
+             * in_vec lives in NS memory and may be mutated concurrently (a
+             * preempting NS interrupt or NS-accessible DMA), so re-reading
+             * in_vec[1].len after the bounds check would allow a TOCTOU
+             * double-fetch to grow the copy past WOLFBOOT_PS_MAX_DATA. */
+            data_len = in_vec[1].len;
             if (uid == NULL || flags == NULL) {
                 return PSA_ERROR_INVALID_ARGUMENT;
             }
-            if (in_vec[1].len > WOLFBOOT_PS_MAX_DATA) {
+            if (data_len > WOLFBOOT_PS_MAX_DATA) {
                 return PSA_ERROR_INSUFFICIENT_STORAGE;
             }
             entry = wolfboot_ps_find(*uid);
@@ -787,13 +794,13 @@ int32_t arm_tee_psa_call(psa_handle_t handle, int32_t type,
             } else if ((entry->flags & PSA_STORAGE_FLAG_WRITE_ONCE) != 0U) {
                 return PSA_ERROR_NOT_PERMITTED;
             }
-            if (in_vec[1].len > 0 && data == NULL) {
+            if (data_len > 0 && data == NULL) {
                 return PSA_ERROR_INVALID_ARGUMENT;
             }
-            if (in_vec[1].len > 0) {
-                XMEMCPY(entry->data, data, in_vec[1].len);
+            if (data_len > 0) {
+                XMEMCPY(entry->data, data, data_len);
             }
-            entry->size = in_vec[1].len;
+            entry->size = data_len;
             entry->flags = *flags;
             return PSA_SUCCESS;
         }

src/fdt.c

@@ -125,6 +125,8 @@ static uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
 {
     const uint32_t *tagp, *lenp;
     uint32_t tag;
+    uint32_t proplen;
+    uint64_t next_off;
     int offset = startoffset;
     const char *p;
 
@@ -152,13 +154,30 @@ static uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
         if (!lenp) {
             return FDT_END; /* premature end */
         }
-        /* skip-name offset, length and value */
-        offset += sizeof(struct fdt_property) - FDT_TAGSIZE
-            + fdt32_to_cpu(*lenp);
-        if (fdt_version(fdt) < 0x10 && fdt32_to_cpu(*lenp) >= 8 &&
-            ((offset - fdt32_to_cpu(*lenp)) % 8) != 0) {
-            offset += 4;
+        proplen = fdt32_to_cpu(*lenp);
+        /* A property value can never be larger than the blob itself.
+         * Reject an oversized length up front: otherwise the unsigned
+         * cursor arithmetic below wraps (e.g. len=0xFFFFFFFF advances
+         * offset by only 7 bytes), the malformed node slips past the
+         * fdt_offset_ptr() bounds check, and the bogus length propagates
+         * to callers as a negative int (a ~4GB memcpy size). */
+        if (proplen > (uint32_t)fdt_totalsize(fdt)) {
+            return FDT_END; /* bad structure */
         }
+        /* skip-name offset, length and value. Accumulate the next cursor in a
+         * 64-bit unsigned so neither the addition nor the narrowing back to the
+         * signed int offset can overflow, then re-validate it against the blob
+         * size before continuing. */
+        next_off = (uint64_t)offset
+            + (sizeof(struct fdt_property) - FDT_TAGSIZE) + proplen;
+        if (fdt_version(fdt) < 0x10 && proplen >= 8 &&
+            ((next_off - proplen) % 8) != 0) {
+            next_off += 4;
+        }
+        if (next_off > (uint64_t)fdt_totalsize(fdt)) {
+            return FDT_END; /* bad structure */
+        }
+        offset = (int)next_off;
         break;
 
     case FDT_END:

src/fwtpm_callable.c

@@ -17,6 +17,28 @@
 #include "wolftpm/fwtpm/fwtpm_nv.h"
 #include "wolftpm/tpm2_types.h"
 
+/* Validate that a buffer supplied by the non-secure caller lives in the
+ * non-secure world before the secure side dereferences it. Without this check a
+ * non-secure caller could pass a pointer into Secure SRAM and turn this veneer
+ * into a confused-deputy primitive (forging TPM responses into Secure memory or
+ * leaking Secure memory through the command path). The relevant property is the
+ * Secure/Non-secure attribution (SAU/IDAU): only CMSE_NONSECURE is checked, not
+ * the MPU read/write permission bits. The MPU bits depend on an enabled NS MPU
+ * (they read back as 0 when NO_MPU is set) and do not constrain Secure accesses
+ * to NS memory anyway, so requiring them would wrongly reject valid NS buffers.
+ * Outside of a CMSE secure build there is no security boundary, so the checks
+ * collapse to a simple non-NULL pass-through. */
+#if defined(__ARM_FEATURE_CMSE) && (__ARM_FEATURE_CMSE == 3U)
+#include <arm_cmse.h>
+#define WCS_FWTPM_NS_RW(p, sz) \
+    cmse_check_address_range((void*)(p), (size_t)(sz), CMSE_NONSECURE)
+#define WCS_FWTPM_NS_R(p, sz) \
+    cmse_check_address_range((void*)(p), (size_t)(sz), CMSE_NONSECURE)
+#else
+#define WCS_FWTPM_NS_RW(p, sz) ((void*)(p))
+#define WCS_FWTPM_NS_R(p, sz)  ((void*)(p))
+#endif
+
 static FWTPM_CTX fwtpm_ctx;
 static int fwtpm_ready;
 
@@ -129,11 +151,18 @@ int CSME_NSE_API wcs_fwtpm_transmit(const uint8_t *cmd, uint32_t cmdSz,
             cmdSz > WCS_FWTPM_MAX_COMMAND_SIZE) {
         return BAD_FUNC_ARG;
     }
+    if (WCS_FWTPM_NS_R(cmd, cmdSz) == NULL ||
+            WCS_FWTPM_NS_RW(rspSz, sizeof(*rspSz)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
 
     rspCapacity = *rspSz;
     if (rspCapacity == 0U || rspCapacity > WCS_FWTPM_MAX_COMMAND_SIZE) {
         return BAD_FUNC_ARG;
     }
+    if (WCS_FWTPM_NS_RW(rsp, rspCapacity) == NULL) {
+        return BAD_FUNC_ARG;
+    }
 
     rspLen = (int)rspCapacity;
     rc = FWTPM_ProcessCommand(&fwtpm_ctx, cmd, (int)cmdSz, rsp, &rspLen, 0);

src/libwolfboot.c

@@ -2419,6 +2419,25 @@ int wolfBoot_ram_decrypt(uint8_t *src, uint8_t *dst)
 #endif /* EXT_ENCRYPTED */
 
 #if defined(__WOLFBOOT) && defined(TZEN)
+
+/* The wolfBoot_nsc_* functions are cmse_nonsecure_entry veneers callable by any
+ * non-secure code. Pointer arguments arrive directly from the NS caller and are
+ * used as the write target of the secure callee. Validate the whole range lives
+ * in the non-secure world before writing, otherwise an NS caller could aim the
+ * write at Secure SRAM (a confused-deputy write primitive). The check verifies
+ * only the Secure/Non-secure attribution (CMSE_NONSECURE); the MPU read/write
+ * permission bits are deliberately not required, as they read back as 0 when the
+ * NS MPU is disabled (NO_MPU) and do not constrain Secure accesses to NS memory
+ * anyway. Outside a CMSE secure build there is no security boundary, so the check
+ * collapses to a non-NULL pass-through. Same fix pattern as F-4416/F-4417/F-4644. */
+#if defined(__ARM_FEATURE_CMSE) && (__ARM_FEATURE_CMSE == 3U)
+#include <arm_cmse.h>
+#define WOLFBOOT_NSC_NS_RW(p, sz) \
+    cmse_check_address_range((void*)(p), (size_t)(sz), CMSE_NONSECURE)
+#else
+#define WOLFBOOT_NSC_NS_RW(p, sz) ((void*)(p))
+#endif
+
 CSME_NSE_API
 void wolfBoot_nsc_success(void)
 {
@@ -2440,6 +2459,8 @@ uint32_t wolfBoot_nsc_get_image_version(uint8_t part)
 CSME_NSE_API
 int wolfBoot_nsc_get_partition_state(uint8_t part, uint8_t *st)
 {
+    if (WOLFBOOT_NSC_NS_RW(st, sizeof(uint8_t)) == NULL)
+        return -1;
     return wolfBoot_get_partition_state(part, st);
 }
 

src/pci.c

@@ -481,6 +481,15 @@ static int pci_program_bar(uint8_t bus, uint8_t dev, uint8_t fun,
                     (is_mmio ? "mm" : "io"), bus, dev, fun, bar_idx,
                      (uint32_t)bar_value, *is_64bit ? "64bit" : "",
                      is_prefetch ? "prefetch" : "");
+    /* A BAR with no writable address bits (bar_align == 0) is unimplemented
+     * or malformed: (~0) + 1 would wrap to length 0, leaving the allocator
+     * cursor unchanged and colliding the next BAR onto the same address.
+     * Treat it as unimplemented and skip it.  Legitimate MMIO BARs always
+     * have at least one writable address bit; IO BARs force the high bits
+     * above, so bar_align is never 0 for them. */
+    if (bar_align == 0)
+        goto restore_bar;
+
     align = length = (~bar_align) + 1;
     /* force pci address to be on page boundary */
     if (align < 0x1000)

src/pkcs11_store.c

@@ -127,6 +127,12 @@ static void bitmap_put(uint32_t pos, int val)
     uint32_t bit = pos % 8;
     uint8_t *bitmap = cached_sector + sizeof(uint32_t);
 
+    /* Reject out-of-range positions (e.g. a power-fault-corrupted hdr->pos
+     * left as erased flash) to avoid an out-of-bounds write past the
+     * bitmap, which lives within cached_sector. */
+    if (pos >= KEYVAULT_MAX_ITEMS)
+        return;
+
     if (val != 0) {
         bitmap[octet] |= (1 << bit);
     } else {

src/tpm.c

@@ -1230,14 +1230,41 @@ static int wolfRNG_GetSeedCB(OS_Seed* os, uint8_t* seed, uint32_t sz)
 
 
 /* API's that are callable from non-secure code */
+
+/* Validate that a buffer supplied by the non-secure caller lives in the
+ * non-secure world before the secure side dereferences it. Without this check a
+ * non-secure caller could pass a pointer into Secure SRAM and turn these veneers
+ * into a confused-deputy write primitive against Secure memory. The check
+ * verifies only the Secure/Non-secure attribution (CMSE_NONSECURE); the MPU
+ * read/write permission bits are deliberately not required, as they read back as
+ * 0 when the NS MPU is disabled (NO_MPU) and do not constrain Secure accesses to
+ * NS memory anyway. Outside of a CMSE secure build there is no security
+ * boundary, so the checks collapse to a simple non-NULL pass-through. */
+#if defined(__ARM_FEATURE_CMSE) && (__ARM_FEATURE_CMSE == 3U)
+#include <arm_cmse.h>
+#define WOLFBOOT_TPM_NS_RW(p, sz) \
+    cmse_check_address_range((void*)(p), (size_t)(sz), CMSE_NONSECURE)
+#define WOLFBOOT_TPM_NS_R(p, sz) \
+    cmse_check_address_range((void*)(p), (size_t)(sz), CMSE_NONSECURE)
+#else
+#define WOLFBOOT_TPM_NS_RW(p, sz) ((void*)(p))
+#define WOLFBOOT_TPM_NS_R(p, sz)  ((void*)(p))
+#endif
+
 int CSME_NSE_API wolfBoot_tpm2_caps(WOLFTPM2_CAPS* caps)
 {
+    if (WOLFBOOT_TPM_NS_RW(caps, sizeof(*caps)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
     memset(caps, 0, sizeof(*caps));
     return wolfTPM2_GetCapabilities(&wolftpm_dev, caps);
 }
 
 int CSME_NSE_API wolfBoot_tpm2_get_handles(TPM_HANDLE handle, TPML_HANDLE* handles)
 {
+    if (WOLFBOOT_TPM_NS_RW(handles, sizeof(*handles)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
     memset(handles, 0, sizeof(*handles));
     return wolfTPM2_GetHandles(handle, handles);
 }
@@ -1249,6 +1276,9 @@ const char* CSME_NSE_API wolfBoot_tpm2_get_alg_name(TPM_ALG_ID alg,
     if (name == NULL || name_sz <= 0) {
         return NULL;
     }
+    if (WOLFBOOT_TPM_NS_RW(name, name_sz) == NULL) {
+        return NULL;
+    }
     s_name = TPM2_GetAlgName(alg);
     if (s_name != NULL && name != NULL && name_sz > 0) {
         strncpy(name, s_name, name_sz - 1);
@@ -1267,6 +1297,9 @@ const char* CSME_NSE_API wolfBoot_tpm2_get_rc_string(int rc, char* error, int er
     if (error == NULL || error_sz <= 0) {
         return NULL;
     }
+    if (WOLFBOOT_TPM_NS_RW(error, error_sz) == NULL) {
+        return NULL;
+    }
     s_error = TPM2_GetRCString(rc);
     if (s_error != NULL && error != NULL && error_sz > 0) {
         strncpy(error, s_error, error_sz - 1);
@@ -1281,17 +1314,32 @@ const char* CSME_NSE_API wolfBoot_tpm2_get_rc_string(int rc, char* error, int er
 
 int CSME_NSE_API wolfBoot_tpm2_get_capability(GetCapability_In* in, GetCapability_Out* out)
 {
+    if (WOLFBOOT_TPM_NS_R(in, sizeof(*in)) == NULL ||
+        WOLFBOOT_TPM_NS_RW(out, sizeof(*out)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
     return (int)TPM2_GetCapability(in, out);
 }
 
 int CSME_NSE_API wolfBoot_tpm2_read_pcr(uint8_t pcrIndex, uint8_t* digest, int* digestSz)
 {
+    if (WOLFBOOT_TPM_NS_RW(digest,
+            TPM2_GetHashDigestSize(WOLFBOOT_TPM_PCR_ALG)) == NULL ||
+        WOLFBOOT_TPM_NS_RW(digestSz, sizeof(*digestSz)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
     return wolfTPM2_ReadPCR(&wolftpm_dev, pcrIndex, WOLFBOOT_TPM_PCR_ALG,
         digest, digestSz);
 }
 
 int CSME_NSE_API wolfBoot_tpm2_read_cert(uint32_t handle, uint8_t* cert, uint32_t* certSz)
 {
+    if (WOLFBOOT_TPM_NS_RW(certSz, sizeof(*certSz)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
+    if (WOLFBOOT_TPM_NS_RW(cert, *certSz) == NULL) {
+        return BAD_FUNC_ARG;
+    }
     wolfTPM2_SetAuthPassword(&wolftpm_dev, 0, NULL);
     return wolfTPM2_NVReadCert(&wolftpm_dev, handle, cert, certSz);
 }
@@ -1304,6 +1352,13 @@ int CSME_NSE_API wolfBoot_tpm2_get_aik(WOLFTPM2_KEY* aik,
     if (aik == NULL) {
         return BAD_FUNC_ARG;
     }
+    if (WOLFBOOT_TPM_NS_RW(aik, sizeof(*aik)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
+    if (masterPassword != NULL &&
+        WOLFBOOT_TPM_NS_R(masterPassword, masterPasswordSz) == NULL) {
+        return BAD_FUNC_ARG;
+    }
 
     /* Load existing AIK and set auth */
     rc = wolfTPM2_ReadPublicKey(&wolftpm_dev, aik, TPM2_IAK_KEY_HANDLE);
@@ -1330,6 +1385,10 @@ int CSME_NSE_API wolfBoot_tpm2_get_timestamp(WOLFTPM2_KEY* aik, GetTime_Out* get
     if (aik == NULL || getTime == NULL) {
         return BAD_FUNC_ARG;
     }
+    if (WOLFBOOT_TPM_NS_RW(aik, sizeof(*aik)) == NULL ||
+        WOLFBOOT_TPM_NS_RW(getTime, sizeof(*getTime)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
 
     memset(getTime, 0, sizeof(*getTime));
     memset(&eh_handle, 0, sizeof(eh_handle));
@@ -1358,6 +1417,10 @@ int CSME_NSE_API wolfBoot_tpm2_get_timestamp(WOLFTPM2_KEY* aik, GetTime_Out* get
 
 int CSME_NSE_API wolfBoot_tpm2_parse_attest(const TPM2B_ATTEST* in, TPMS_ATTEST* out)
 {
+    if (WOLFBOOT_TPM_NS_R(in, sizeof(*in)) == NULL ||
+        WOLFBOOT_TPM_NS_RW(out, sizeof(*out)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
     return TPM2_ParseAttest(in, out);
 }
 
@@ -1372,6 +1435,11 @@ int CSME_NSE_API wolfBoot_tpm2_quote(WOLFTPM2_KEY* aik,
         quoteResult == NULL) {
         return BAD_FUNC_ARG;
     }
+    if (WOLFBOOT_TPM_NS_RW(aik, sizeof(*aik)) == NULL ||
+        WOLFBOOT_TPM_NS_R(pcrArray, pcrArraySz) == NULL ||
+        WOLFBOOT_TPM_NS_RW(quoteResult, sizeof(*quoteResult)) == NULL) {
+        return BAD_FUNC_ARG;
+    }
 
     /* set auth for using the AIK */
     wolfTPM2_SetAuthHandle(&wolftpm_dev, 0, &aik->handle);

src/wc_callable.c

@@ -34,10 +34,31 @@
 #include "wolfboot/wcs_fwtpm.h"
 #endif
 
+/* wcs_get_random is a cmse_nonsecure_entry veneer: the rand pointer and size
+ * arrive from the non-secure caller and are used as the write target of
+ * wc_RNG_GenerateBlock. Validate the whole range lives in the non-secure world
+ * before writing, otherwise an NS caller could aim the RNG output at Secure SRAM
+ * (a confused-deputy write primitive). The check verifies only the
+ * Secure/Non-secure attribution (CMSE_NONSECURE); the MPU read/write permission
+ * bits are deliberately not required, as they read back as 0 when the NS MPU is
+ * disabled (NO_MPU) and do not constrain Secure accesses to NS memory anyway.
+ * Outside a CMSE secure build there is no security boundary, so the check
+ * collapses to a non-NULL pass-through. */
+#if defined(__ARM_FEATURE_CMSE) && (__ARM_FEATURE_CMSE == 3U)
+#include <arm_cmse.h>
+#define WOLFBOOT_WCS_NS_RW(p, sz) \
+    cmse_check_address_range((void*)(p), (size_t)(sz), CMSE_NONSECURE)
+#else
+#define WOLFBOOT_WCS_NS_RW(p, sz) ((void*)(p))
+#endif
+
 static WC_RNG wcs_rng;
 
 int CSME_NSE_API wcs_get_random(uint8_t *rand, uint32_t size)
 {
+    if (WOLFBOOT_WCS_NS_RW(rand, size) == NULL) {
+        return BAD_FUNC_ARG;
+    }
     return wc_RNG_GenerateBlock(&wcs_rng, rand, size);
 }