diff options
| -rw-r--r-- | subx/012elf.cc | 8 | ||||
| -rw-r--r-- | subx/020syscalls.cc | 5 |
2 files changed, 12 insertions, 1 deletions
diff --git a/subx/012elf.cc b/subx/012elf.cc index a77c6056..2fea60db 100644 --- a/subx/012elf.cc +++ b/subx/012elf.cc @@ -90,7 +90,13 @@ void load_elf_contents(uint8_t* elf_contents, size_t size, int argc, char* argv[ void push(uint32_t val) { Reg[ESP].u -= 4; - assert(Reg[ESP].u >= STACK_SEGMENT); + if (Reg[ESP].u < STACK_SEGMENT) { + raise << "The stack overflowed its segment. " + << "Maybe SPACE_FOR_SEGMENT should be larger? " + << "Or you need to carve out an exception for the stack segment " + << "to be larger.\n" << end(); + exit(1); + } trace(Callstack_depth+1, "run") << "decrementing ESP to 0x" << HEXWORD << Reg[ESP].u << end(); trace(Callstack_depth+1, "run") << "pushing value 0x" << HEXWORD << val << end(); write_mem_u32(Reg[ESP].u, val); diff --git a/subx/020syscalls.cc b/subx/020syscalls.cc index 6b9faa2c..444c9fd5 100644 --- a/subx/020syscalls.cc +++ b/subx/020syscalls.cc @@ -122,5 +122,10 @@ uint32_t new_segment(uint32_t length) { uint32_t result = Next_segment; Mem.push_back(vma(Next_segment, Next_segment+length)); Next_segment -= SPACE_FOR_SEGMENT; + if (Next_segment <= DATA_SEGMENT) { + raise << "Allocated too many segments; the VM ran out of memory. " + << "Maybe SPACE_FOR_SEGMENT can be smaller?\n" << end(); + exit(1); + } return result; } |