elf: Add overlapping PHDR detection
diff --git a/common/lib/elf.c b/common/lib/elf.c
index 321b5411..ed0b63eb 100644
--- a/common/lib/elf.c
+++ b/common/lib/elf.c
@@ -457,6 +457,32 @@ bool elf64_load(uint8_t *elf, uint64_t *entry_point, uint64_t *_slide, uint32_t
continue;
}
+ // check for overlapping phdrs
+ for (uint16_t j = 0; j < hdr->ph_num; j++) {
+ struct elf64_phdr *phdr_in = (void *)elf + (hdr->phoff + j * hdr->phdr_size);
+
+ if (phdr_in->p_type != PT_LOAD) {
+ continue;
+ }
+
+ // Drop entries not in the higher half
+ if (phdr_in->p_vaddr < FIXED_HIGHER_HALF_OFFSET_64) {
+ continue;
+ }
+
+ if (phdr_in == phdr) {
+ continue;
+ }
+
+ if ((phdr_in->p_vaddr >= phdr->p_vaddr
+ && phdr_in->p_vaddr < phdr->p_vaddr + phdr->p_memsz)
+ ||
+ (phdr_in->p_vaddr + phdr_in->p_memsz > phdr->p_vaddr
+ && phdr_in->p_vaddr + phdr_in->p_memsz <= phdr->p_vaddr + phdr->p_memsz)) {
+ panic(true, "elf: Attempted to load ELF file with overlapping PHDRs (%u and %u overlap)", i, j);
+ }
+ }
+
if (phdr->p_vaddr < min_vaddr) {
min_vaddr = phdr->p_vaddr;
}
