/*
* kobj_affix:
*
* Set an object's name and perform global relocs. May only be
* called after the module and any requisite modules are loaded.
*/
int
kobj_affix(kobj_t ko, const char *name)
{
int error;
KASSERT(ko->ko_ksyms == false);
KASSERT(ko->ko_loaded == false);
kobj_setname(ko, name);
/* Cache addresses of undefined symbols. */
error = kobj_checksyms(ko, true);
/* Now do global relocations. */
if (error == 0)
error = kobj_relocate(ko, false);
/*
* Now that we know the name, register the symbol table.
* Do after global relocations because ksyms will pack
* the table.
*/
if (error == 0) {
ksyms_modload(ko->ko_name, ko->ko_symtab, ko->ko_symcnt *
sizeof(Elf_Sym), ko->ko_strtab, ko->ko_strtabsz);
ko->ko_ksyms = true;
}
/* Jettison unneeded memory post-link. */
kobj_jettison(ko);
/*
* Notify MD code that a module has been loaded.
*
* Most architectures use this opportunity to flush their caches.
*/
if (error == 0) {
error = kobj_machdep(ko, (void *)ko->ko_address, ko->ko_size,
true);
if (error != 0)
kobj_error(__func__, __LINE__, ko,
"machine dependent init failed %d", error);
ko->ko_loaded = true;
}
/* If there was an error, destroy the whole object. */
if (error != 0) {
kobj_unload(ko);
}
return error;
}
/*
* kobj_affix:
*
* Set an object's name and perform global relocs. May only be
* called after the module and any requisite modules are loaded.
*/
int
kobj_affix(kobj_t ko, const char *name)
{
int error;
KASSERT(ko->ko_ksyms == false);
KASSERT(ko->ko_loaded == false);
strlcpy(ko->ko_name, name, sizeof(ko->ko_name));
/* Now do global relocations. */
error = kobj_relocate(ko, false);
/*
* Now that we know the name, register the symbol table.
* Do after global relocations because ksyms will pack it.
*/
ksyms_modload(ko->ko_name, ko->ko_symtab, ko->ko_symcnt *
sizeof(Elf_Sym), ko->ko_strtab, ko->ko_strtabsz);
ko->ko_ksyms = true;
/* Jettison unneeded memory post-link. */
kobj_jettison(ko);
/* Notify MD code that a module has been loaded. */
if (error == 0) {
error = kobj_machdep(ko, (void *)ko->ko_address, ko->ko_size,
true);
if (error != 0) {
kobj_error("machine dependent init failed");
}
ko->ko_loaded = true;
}
/* If there was an error, destroy the whole object. */
if (error != 0) {
kobj_unload(ko);
}
return error;
}
/*
* kobj_load:
*
* Load an ELF object and prepare to link into the running kernel
* image.
*/
int
kobj_load(kobj_t ko)
{
Elf_Ehdr *hdr;
Elf_Shdr *shdr;
Elf_Sym *es;
vaddr_t mapbase;
size_t mapsize;
int error;
int symtabindex;
int symstrindex;
int nsym;
int pb, rl, ra;
int alignmask;
int i, j;
void *addr;
KASSERT(ko->ko_type != KT_UNSET);
KASSERT(ko->ko_source != NULL);
shdr = NULL;
mapsize = 0;
error = 0;
hdr = NULL;
/*
* Read the elf header from the file.
*/
error = ko->ko_read(ko, (void **)&hdr, sizeof(*hdr), 0, true);
if (error != 0) {
kobj_error(__func__, __LINE__, ko, "read failed %d", error);
goto out;
}
if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0) {
kobj_error(__func__, __LINE__, ko, "not an ELF object");
error = ENOEXEC;
goto out;
}
if (hdr->e_ident[EI_VERSION] != EV_CURRENT ||
hdr->e_version != EV_CURRENT) {
kobj_error(__func__, __LINE__, ko,
"unsupported file version %d", hdr->e_ident[EI_VERSION]);
error = ENOEXEC;
goto out;
}
if (hdr->e_type != ET_REL) {
kobj_error(__func__, __LINE__, ko, "unsupported file type %d",
hdr->e_type);
error = ENOEXEC;
goto out;
}
switch (hdr->e_machine) {
#if ELFSIZE == 32
ELF32_MACHDEP_ID_CASES
#elif ELFSIZE == 64
ELF64_MACHDEP_ID_CASES
#else
#error not defined
#endif
default:
kobj_error(__func__, __LINE__, ko, "unsupported machine %d",
hdr->e_machine);
error = ENOEXEC;
goto out;
}
ko->ko_nprogtab = 0;
ko->ko_shdr = 0;
ko->ko_nrel = 0;
ko->ko_nrela = 0;
/*
* Allocate and read in the section header.
*/
ko->ko_shdrsz = hdr->e_shnum * hdr->e_shentsize;
if (ko->ko_shdrsz == 0 || hdr->e_shoff == 0 ||
hdr->e_shentsize != sizeof(Elf_Shdr)) {
kobj_error(__func__, __LINE__, ko, "bad sizes");
error = ENOEXEC;
goto out;
}
error = ko->ko_read(ko, (void **)&shdr, ko->ko_shdrsz, hdr->e_shoff,
true);
if (error != 0) {
kobj_error(__func__, __LINE__, ko, "read failed %d", error);
goto out;
}
ko->ko_shdr = shdr;
/*
* Scan the section header for information and table sizing.
*/
nsym = 0;
symtabindex = -1;
symstrindex = -1;
for (i = 0; i < hdr->e_shnum; i++) {
switch (shdr[i].sh_type) {
case SHT_PROGBITS:
case SHT_NOBITS:
ko->ko_nprogtab++;
break;
case SHT_SYMTAB:
nsym++;
symtabindex = i;
symstrindex = shdr[i].sh_link;
break;
case SHT_REL:
if (shdr[shdr[i].sh_info].sh_type != SHT_PROGBITS)
continue;
ko->ko_nrel++;
break;
case SHT_RELA:
if (shdr[shdr[i].sh_info].sh_type != SHT_PROGBITS)
continue;
ko->ko_nrela++;
break;
case SHT_STRTAB:
break;
}
}
if (ko->ko_nprogtab == 0) {
kobj_error(__func__, __LINE__, ko, "file has no contents");
error = ENOEXEC;
goto out;
}
if (nsym != 1) {
/* Only allow one symbol table for now */
kobj_error(__func__, __LINE__, ko,
"file has no valid symbol table");
error = ENOEXEC;
goto out;
}
if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
shdr[symstrindex].sh_type != SHT_STRTAB) {
kobj_error(__func__, __LINE__, ko,
"file has invalid symbol strings");
error = ENOEXEC;
goto out;
}
/*
* Allocate space for tracking the load chunks.
*/
if (ko->ko_nprogtab != 0) {
ko->ko_progtab = kmem_zalloc(ko->ko_nprogtab *
sizeof(*ko->ko_progtab), KM_SLEEP);
if (ko->ko_progtab == NULL) {
error = ENOMEM;
kobj_error(__func__, __LINE__, ko, "out of memory");
goto out;
}
}
if (ko->ko_nrel != 0) {
ko->ko_reltab = kmem_zalloc(ko->ko_nrel *
sizeof(*ko->ko_reltab), KM_SLEEP);
if (ko->ko_reltab == NULL) {
error = ENOMEM;
kobj_error(__func__, __LINE__, ko, "out of memory");
goto out;
}
}
if (ko->ko_nrela != 0) {
ko->ko_relatab = kmem_zalloc(ko->ko_nrela *
sizeof(*ko->ko_relatab), KM_SLEEP);
if (ko->ko_relatab == NULL) {
error = ENOMEM;
kobj_error(__func__, __LINE__, ko, "out of memory");
goto out;
}
}
if (symtabindex == -1) {
kobj_error(__func__, __LINE__, ko, "lost symbol table index");
goto out;
}
/*
* Allocate space for and load the symbol table.
*/
ko->ko_symcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
if (ko->ko_symcnt == 0) {
kobj_error(__func__, __LINE__, ko, "no symbol table");
goto out;
}
error = ko->ko_read(ko, (void **)&ko->ko_symtab,
ko->ko_symcnt * sizeof(Elf_Sym),
shdr[symtabindex].sh_offset, true);
if (error != 0) {
kobj_error(__func__, __LINE__, ko, "read failed %d", error);
goto out;
}
/*
* Allocate space for and load the symbol strings.
*/
ko->ko_strtabsz = shdr[symstrindex].sh_size;
if (ko->ko_strtabsz == 0) {
kobj_error(__func__, __LINE__, ko, "no symbol strings");
goto out;
}
error = ko->ko_read(ko, (void *)&ko->ko_strtab, ko->ko_strtabsz,
shdr[symstrindex].sh_offset, true);
if (error != 0) {
kobj_error(__func__, __LINE__, ko, "read failed %d", error);
goto out;
}
/*
* Adjust module symbol namespace, if necessary (e.g. with rump)
*/
error = kobj_renamespace(ko->ko_symtab, ko->ko_symcnt,
&ko->ko_strtab, &ko->ko_strtabsz);
if (error != 0) {
kobj_error(__func__, __LINE__, ko, "renamespace failed %d",
error);
goto out;
}
/*
* Do we have a string table for the section names?
*/
if (hdr->e_shstrndx != 0 && shdr[hdr->e_shstrndx].sh_size != 0 &&
shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
ko->ko_shstrtabsz = shdr[hdr->e_shstrndx].sh_size;
error = ko->ko_read(ko, (void **)&ko->ko_shstrtab,
shdr[hdr->e_shstrndx].sh_size,
shdr[hdr->e_shstrndx].sh_offset, true);
if (error != 0) {
kobj_error(__func__, __LINE__, ko, "read failed %d",
error);
goto out;
}
}
/*
* Size up code/data(progbits) and bss(nobits).
*/
alignmask = 0;
mapbase = 0;
for (i = 0; i < hdr->e_shnum; i++) {
switch (shdr[i].sh_type) {
case SHT_PROGBITS:
case SHT_NOBITS:
if (mapbase == 0)
mapbase = shdr[i].sh_offset;
alignmask = shdr[i].sh_addralign - 1;
mapsize += alignmask;
mapsize &= ~alignmask;
mapsize += shdr[i].sh_size;
break;
}
}
/*
* We know how much space we need for the text/data/bss/etc.
* This stuff needs to be in a single chunk so that profiling etc
* can get the bounds and gdb can associate offsets with modules.
*/
if (mapsize == 0) {
kobj_error(__func__, __LINE__, ko, "no text/data/bss");
goto out;
}
if (ko->ko_type == KT_MEMORY) {
mapbase += (vaddr_t)ko->ko_source;
} else {
mapbase = uvm_km_alloc(module_map, round_page(mapsize),
0, UVM_KMF_WIRED | UVM_KMF_EXEC);
if (mapbase == 0) {
kobj_error(__func__, __LINE__, ko, "out of memory");
error = ENOMEM;
goto out;
}
}
ko->ko_address = mapbase;
ko->ko_size = mapsize;
/*
* Now load code/data(progbits), zero bss(nobits), allocate space
* for and load relocs
*/
pb = 0;
rl = 0;
ra = 0;
alignmask = 0;
for (i = 0; i < hdr->e_shnum; i++) {
switch (shdr[i].sh_type) {
case SHT_PROGBITS:
case SHT_NOBITS:
alignmask = shdr[i].sh_addralign - 1;
if (ko->ko_type == KT_MEMORY) {
addr = (void *)(shdr[i].sh_offset +
(vaddr_t)ko->ko_source);
if (((vaddr_t)addr & alignmask) != 0) {
kobj_error(__func__, __LINE__, ko,
"section %d not aligned",
i);
goto out;
}
} else {
mapbase += alignmask;
mapbase &= ~alignmask;
addr = (void *)mapbase;
mapbase += shdr[i].sh_size;
}
ko->ko_progtab[pb].addr = addr;
if (shdr[i].sh_type == SHT_PROGBITS) {
ko->ko_progtab[pb].name = "<<PROGBITS>>";
error = ko->ko_read(ko, &addr,
shdr[i].sh_size, shdr[i].sh_offset, false);
if (error != 0) {
kobj_error(__func__, __LINE__, ko,
"read failed %d", error);
goto out;
}
} else if (ko->ko_type == KT_MEMORY &&
shdr[i].sh_size != 0) {
kobj_error(__func__, __LINE__, ko,
"non-loadable BSS "
"section in pre-loaded module");
error = EINVAL;
goto out;
} else {
ko->ko_progtab[pb].name = "<<NOBITS>>";
memset(addr, 0, shdr[i].sh_size);
}
ko->ko_progtab[pb].size = shdr[i].sh_size;
ko->ko_progtab[pb].sec = i;
if (ko->ko_shstrtab != NULL && shdr[i].sh_name != 0) {
ko->ko_progtab[pb].name =
ko->ko_shstrtab + shdr[i].sh_name;
}
/* Update all symbol values with the offset. */
for (j = 0; j < ko->ko_symcnt; j++) {
es = &ko->ko_symtab[j];
if (es->st_shndx != i) {
continue;
}
es->st_value += (Elf_Addr)addr;
}
pb++;
break;
case SHT_REL:
if (shdr[shdr[i].sh_info].sh_type != SHT_PROGBITS)
break;
ko->ko_reltab[rl].size = shdr[i].sh_size;
ko->ko_reltab[rl].size -=
shdr[i].sh_size % sizeof(Elf_Rel);
if (ko->ko_reltab[rl].size != 0) {
ko->ko_reltab[rl].nrel =
shdr[i].sh_size / sizeof(Elf_Rel);
ko->ko_reltab[rl].sec = shdr[i].sh_info;
error = ko->ko_read(ko,
(void **)&ko->ko_reltab[rl].rel,
ko->ko_reltab[rl].size,
shdr[i].sh_offset, true);
if (error != 0) {
kobj_error(__func__, __LINE__, ko,
"read failed %d", error);
goto out;
}
}
rl++;
break;
case SHT_RELA:
if (shdr[shdr[i].sh_info].sh_type != SHT_PROGBITS)
break;
ko->ko_relatab[ra].size = shdr[i].sh_size;
ko->ko_relatab[ra].size -=
shdr[i].sh_size % sizeof(Elf_Rela);
if (ko->ko_relatab[ra].size != 0) {
ko->ko_relatab[ra].nrela =
shdr[i].sh_size / sizeof(Elf_Rela);
ko->ko_relatab[ra].sec = shdr[i].sh_info;
error = ko->ko_read(ko,
(void **)&ko->ko_relatab[ra].rela,
shdr[i].sh_size,
shdr[i].sh_offset, true);
if (error != 0) {
kobj_error(__func__, __LINE__, ko,
"read failed %d", error);
goto out;
}
}
ra++;
break;
default:
break;
}
}
if (pb != ko->ko_nprogtab) {
panic("%s:%d: %s: lost progbits", __func__, __LINE__,
ko->ko_name);
}
if (rl != ko->ko_nrel) {
panic("%s:%d: %s: lost rel", __func__, __LINE__,
ko->ko_name);
}
if (ra != ko->ko_nrela) {
panic("%s:%d: %s: lost rela", __func__, __LINE__,
ko->ko_name);
}
if (ko->ko_type != KT_MEMORY && mapbase != ko->ko_address + mapsize) {
panic("%s:%d: %s: "
"mapbase 0x%lx != address %lx + mapsize %ld (0x%lx)\n",
__func__, __LINE__, ko->ko_name,
(long)mapbase, (long)ko->ko_address, (long)mapsize,
(long)ko->ko_address + mapsize);
}
/*
* Perform local relocations only. Relocations relating to global
* symbols will be done by kobj_affix().
*/
error = kobj_checksyms(ko, false);
if (error == 0) {
error = kobj_relocate(ko, true);
}
out:
if (hdr != NULL) {
kobj_free(ko, hdr, sizeof(*hdr));
}
kobj_close(ko);
if (error != 0) {
kobj_unload(ko);
}
return error;
}
