diff options
| -rw-r--r-- | exec/exec.c | 57 |
1 files changed, 42 insertions, 15 deletions
diff --git a/exec/exec.c b/exec/exec.c index 3b63b7f6..ea352fa8 100644 --- a/exec/exec.c +++ b/exec/exec.c @@ -47,11 +47,12 @@ pthread_rwlock_t std_lock = PTHREAD_RWLOCK_INITIALIZER; #include <hurd/sigpreempt.h> -/* Load or allocate a section. */ -static void +/* Load or allocate a section. + Returns the address of the end of the section. */ +static vm_address_t load_section (void *section, struct execdata *u) { - vm_address_t addr = 0; + vm_address_t addr = 0, end = 0; vm_offset_t filepos = 0; vm_size_t filesz = 0, memsz = 0; vm_prot_t vm_prot; @@ -60,7 +61,7 @@ load_section (void *section, struct execdata *u) const ElfW(Phdr) *const ph = section; if (u->error) - return; + return 0; vm_prot = VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE; @@ -97,9 +98,11 @@ load_section (void *section, struct execdata *u) if (anywhere && addr < vm_page_size) addr = vm_page_size; + end = addr + memsz; + if (memsz == 0) /* This section is empty; ignore it. */ - return; + return 0; if (filesz != 0) { @@ -173,7 +176,7 @@ load_section (void *section, struct execdata *u) write_to_task (mapstart, size, vm_prot, (vm_address_t) buf); } if (u->error) - return; + return 0; if (anywhere) { @@ -230,7 +233,7 @@ load_section (void *section, struct execdata *u) { maplose: vm_deallocate (u->task, mapstart, filesz); - return; + return 0; } } @@ -294,7 +297,7 @@ load_section (void *section, struct execdata *u) mask, anywhere, MACH_PORT_NULL, 0, 1, vm_prot, VM_PROT_ALL, VM_INHERIT_COPY); if (u->error) - return; + return 0; } if (anywhere) @@ -319,7 +322,7 @@ load_section (void *section, struct execdata *u) if (u->error) { vm_deallocate (u->task, mapstart, memsz); - return; + return 0; } u->error = hurd_safe_memset ( (void *) (ourpage + (addr - overlap_page)), @@ -335,6 +338,7 @@ load_section (void *section, struct execdata *u) munmap ((caddr_t) ourpage, size); } } + return end; } /* XXX all accesses of the mapped data need to use fault handling @@ -717,18 +721,37 @@ set_name (task_t task, const char *exec_name, pid_t pid) free (name); } -/* Load the file. */ -static void -load (task_t usertask, struct execdata *e) +/* Load the file. Returns the address of the end of the load. */ +static vm_offset_t +load (task_t usertask, struct execdata *e, vm_offset_t anywhere_start) { + int anywhere = e->info.elf.anywhere; + vm_offset_t end; e->task = usertask; if (! e->error) { ElfW(Word) i; + + if (anywhere && anywhere_start) + { + /* Make sure this anywhere-load will go at the end of the previous + anywhere-load. */ + /* TODO: Rather compute how much contiguous room is needed, allocate + the area from the kernel, and then map memory sections. */ + /* TODO: Possibly implement Adresse Space Layout Randomization. */ + e->info.elf.loadbase = anywhere_start; + e->info.elf.anywhere = 0; + } + for (i = 0; i < e->info.elf.phnum; ++i) if (e->info.elf.phdr[i].p_type == PT_LOAD) - load_section (&e->info.elf.phdr[i], e); + { + end = load_section (&e->info.elf.phdr[i], e); + if (anywhere && end > anywhere_start) + /* This section pushes the next anywhere-load further */ + anywhere_start = end; + } /* The entry point address is relative to wherever we loaded the program text. */ @@ -737,6 +760,9 @@ load (task_t usertask, struct execdata *e) /* Release the conch for the file. */ finish_mapping (e); + + /* Return potentially-new start for anywhere-loads. */ + return round_page (anywhere_start); } @@ -783,6 +809,7 @@ do_exec (file_t file, mach_msg_type_number_t i; int intarray_dealloc = 0; /* Dealloc INTARRAY before returning? */ int oldtask_trashed = 0; /* Have we trashed the old task? */ + vm_address_t anywhere_start = 0; /* Prime E for executing FILE and check its validity. This must be an inline function because it stores pointers into alloca'd storage in E @@ -1156,7 +1183,7 @@ do_exec (file_t file, if (interp.file != MACH_PORT_NULL) { /* Load the interpreter file. */ - load (newtask, &interp); + anywhere_start = load (newtask, &interp, anywhere_start); if (interp.error) { e.error = interp.error; @@ -1167,7 +1194,7 @@ do_exec (file_t file, /* Load the file into the task. */ - load (newtask, &e); + anywhere_start = load (newtask, &e, anywhere_start); if (e.error) goto out; |