Commit ac3b4328 authored by Song Liu's avatar Song Liu Committed by Luis Chamberlain

module: replace module_layout with module_memory

module_layout manages different types of memory (text, data, rodata, etc.)
in one allocation, which is problematic for some reasons:

1. It is hard to enable CONFIG_STRICT_MODULE_RWX.
2. It is hard to use huge pages in modules (and not break strict rwx).
3. Many archs uses module_layout for arch-specific data, but it is not
   obvious how these data are used (are they RO, RX, or RW?)

Improve the scenario by replacing 2 (or 3) module_layout per module with
up to 7 module_memory per module:

        MOD_TEXT,
        MOD_DATA,
        MOD_RODATA,
        MOD_RO_AFTER_INIT,
        MOD_INIT_TEXT,
        MOD_INIT_DATA,
        MOD_INIT_RODATA,

and allocating them separately. This adds slightly more entries to
mod_tree (from up to 3 entries per module, to up to 7 entries per
module). However, this at most adds a small constant overhead to
__module_address(), which is expected to be fast.

Various archs use module_layout for different data. These data are put
into different module_memory based on their location in module_layout.
IOW, data that used to go with text is allocated with MOD_MEM_TYPE_TEXT;
data that used to go with data is allocated with MOD_MEM_TYPE_DATA, etc.

module_memory simplifies quite some of the module code. For example,
ARCH_WANTS_MODULES_DATA_IN_VMALLOC is a lot cleaner, as it just uses a
different allocator for the data. kernel/module/strict_rwx.c is also
much cleaner with module_memory.
Signed-off-by: default avatarSong Liu <song@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
parent fe15c26e
......@@ -369,6 +369,8 @@ void *unwind_add_table(struct module *module, const void *table_start,
unsigned long table_size)
{
struct unwind_table *table;
struct module_memory *core_text;
struct module_memory *init_text;
if (table_size <= 0)
return NULL;
......@@ -377,11 +379,11 @@ void *unwind_add_table(struct module *module, const void *table_start,
if (!table)
return NULL;
init_unwind_table(table, module->name,
module->core_layout.base, module->core_layout.size,
module->init_layout.base, module->init_layout.size,
table_start, table_size,
NULL, 0);
core_text = &module->mem[MOD_TEXT];
init_text = &module->mem[MOD_INIT_TEXT];
init_unwind_table(table, module->name, core_text->base, core_text->size,
init_text->base, init_text->size, table_start, table_size, NULL, 0);
init_unwind_hdr(table, unw_hdr_alloc);
......
......@@ -28,11 +28,6 @@ static const u32 fixed_plts[] = {
#endif
};
static bool in_init(const struct module *mod, unsigned long loc)
{
return loc - (u32)mod->init_layout.base < mod->init_layout.size;
}
static void prealloc_fixed(struct mod_plt_sec *pltsec, struct plt_entries *plt)
{
int i;
......@@ -50,8 +45,8 @@ static void prealloc_fixed(struct mod_plt_sec *pltsec, struct plt_entries *plt)
u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val)
{
struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
&mod->arch.init;
struct mod_plt_sec *pltsec = !within_module_init(loc, mod) ?
&mod->arch.core : &mod->arch.init;
struct plt_entries *plt;
int idx;
......
......@@ -65,17 +65,12 @@ static bool plt_entries_equal(const struct plt_entry *a,
(q + aarch64_insn_adrp_get_offset(le32_to_cpu(b->adrp)));
}
static bool in_init(const struct module *mod, void *loc)
{
return (u64)loc - (u64)mod->init_layout.base < mod->init_layout.size;
}
u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs,
void *loc, const Elf64_Rela *rela,
Elf64_Sym *sym)
{
struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
&mod->arch.init;
struct mod_plt_sec *pltsec = !within_module_init((unsigned long)loc, mod) ?
&mod->arch.core : &mod->arch.init;
struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr;
int i = pltsec->plt_num_entries;
int j = i - 1;
......@@ -105,8 +100,8 @@ u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs,
u64 module_emit_veneer_for_adrp(struct module *mod, Elf64_Shdr *sechdrs,
void *loc, u64 val)
{
struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
&mod->arch.init;
struct mod_plt_sec *pltsec = !within_module_init((unsigned long)loc, mod) ?
&mod->arch.core : &mod->arch.init;
struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr;
int i = pltsec->plt_num_entries++;
u32 br;
......
......@@ -485,19 +485,19 @@ module_frob_arch_sections (Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, char *secstrings,
return 0;
}
static inline int
static inline bool
in_init (const struct module *mod, uint64_t addr)
{
return addr - (uint64_t) mod->init_layout.base < mod->init_layout.size;
return within_module_init(addr, mod);
}
static inline int
static inline bool
in_core (const struct module *mod, uint64_t addr)
{
return addr - (uint64_t) mod->core_layout.base < mod->core_layout.size;
return within_module_core(addr, mod);
}
static inline int
static inline bool
is_internal (const struct module *mod, uint64_t value)
{
return in_init(mod, value) || in_core(mod, value);
......@@ -677,7 +677,8 @@ do_reloc (struct module *mod, uint8_t r_type, Elf64_Sym *sym, uint64_t addend,
break;
case RV_BDREL:
val -= (uint64_t) (in_init(mod, val) ? mod->init_layout.base : mod->core_layout.base);
val -= (uint64_t) (in_init(mod, val) ? mod->mem[MOD_INIT_TEXT].base :
mod->mem[MOD_TEXT].base);
break;
case RV_LTV:
......@@ -812,15 +813,18 @@ apply_relocate_add (Elf64_Shdr *sechdrs, const char *strtab, unsigned int symind
* addresses have been selected...
*/
uint64_t gp;
if (mod->core_layout.size > MAX_LTOFF)
struct module_memory *mod_mem;
mod_mem = &mod->mem[MOD_DATA];
if (mod_mem->size > MAX_LTOFF)
/*
* This takes advantage of fact that SHF_ARCH_SMALL gets allocated
* at the end of the module.
*/
gp = mod->core_layout.size - MAX_LTOFF / 2;
gp = mod_mem->size - MAX_LTOFF / 2;
else
gp = mod->core_layout.size / 2;
gp = (uint64_t) mod->core_layout.base + ((gp + 7) & -8);
gp = mod_mem->size / 2;
gp = (uint64_t) mod_mem->base + ((gp + 7) & -8);
mod->arch.gp = gp;
DEBUGP("%s: placing gp at 0x%lx\n", __func__, gp);
}
......
......@@ -199,18 +199,17 @@ static void layout_sections(struct module *mod, const Elf_Ehdr *hdr,
for (m = 0; m < ARRAY_SIZE(masks); ++m) {
for (i = 0; i < hdr->e_shnum; ++i) {
Elf_Shdr *s = &sechdrs[i];
struct module_memory *mod_mem;
mod_mem = &mod->mem[MOD_TEXT];
if ((s->sh_flags & masks[m][0]) != masks[m][0]
|| (s->sh_flags & masks[m][1])
|| s->sh_entsize != ~0UL)
continue;
s->sh_entsize =
get_offset((unsigned long *)&mod->core_layout.size, s);
get_offset((unsigned long *)&mod_mem->size, s);
}
if (m == 0)
mod->core_layout.text_size = mod->core_layout.size;
}
}
......@@ -641,7 +640,7 @@ static int vpe_elfload(struct vpe *v)
layout_sections(&mod, hdr, sechdrs, secstrings);
}
v->load_addr = alloc_progmem(mod.core_layout.size);
v->load_addr = alloc_progmem(mod.mod_mem[MOD_TEXT].size);
if (!v->load_addr)
return -ENOMEM;
......
......@@ -27,9 +27,9 @@
* We are not doing SEGREL32 handling correctly. According to the ABI, we
* should do a value offset, like this:
* if (in_init(me, (void *)val))
* val -= (uint32_t)me->init_layout.base;
* val -= (uint32_t)me->mem[MOD_INIT_TEXT].base;
* else
* val -= (uint32_t)me->core_layout.base;
* val -= (uint32_t)me->mem[MOD_TEXT].base;
* However, SEGREL32 is used only for PARISC unwind entries, and we want
* those entries to have an absolute address, and not just an offset.
*
......@@ -76,25 +76,6 @@
* allows us to allocate up to 4095 GOT entries. */
#define MAX_GOTS 4095
/* three functions to determine where in the module core
* or init pieces the location is */
static inline int in_init(struct module *me, void *loc)
{
return (loc >= me->init_layout.base &&
loc <= (me->init_layout.base + me->init_layout.size));
}
static inline int in_core(struct module *me, void *loc)
{
return (loc >= me->core_layout.base &&
loc <= (me->core_layout.base + me->core_layout.size));
}
static inline int in_local(struct module *me, void *loc)
{
return in_init(me, loc) || in_core(me, loc);
}
#ifndef CONFIG_64BIT
struct got_entry {
Elf32_Addr addr;
......@@ -302,6 +283,7 @@ int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
{
unsigned long gots = 0, fdescs = 0, len;
unsigned int i;
struct module_memory *mod_mem;
len = hdr->e_shnum * sizeof(me->arch.section[0]);
me->arch.section = kzalloc(len, GFP_KERNEL);
......@@ -346,14 +328,15 @@ int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
me->arch.section[s].stub_entries += count;
}
mod_mem = &me->mem[MOD_TEXT];
/* align things a bit */
me->core_layout.size = ALIGN(me->core_layout.size, 16);
me->arch.got_offset = me->core_layout.size;
me->core_layout.size += gots * sizeof(struct got_entry);
mod_mem->size = ALIGN(mod_mem->size, 16);
me->arch.got_offset = mod_mem->size;
mod_mem->size += gots * sizeof(struct got_entry);
me->core_layout.size = ALIGN(me->core_layout.size, 16);
me->arch.fdesc_offset = me->core_layout.size;
me->core_layout.size += fdescs * sizeof(Elf_Fdesc);
mod_mem->size = ALIGN(mod_mem->size, 16);
me->arch.fdesc_offset = mod_mem->size;
mod_mem->size += fdescs * sizeof(Elf_Fdesc);
me->arch.got_max = gots;
me->arch.fdesc_max = fdescs;
......@@ -371,7 +354,7 @@ static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
BUG_ON(value == 0);
got = me->core_layout.base + me->arch.got_offset;
got = me->mem[MOD_TEXT].base + me->arch.got_offset;
for (i = 0; got[i].addr; i++)
if (got[i].addr == value)
goto out;
......@@ -389,7 +372,7 @@ static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
#ifdef CONFIG_64BIT
static Elf_Addr get_fdesc(struct module *me, unsigned long value)
{
Elf_Fdesc *fdesc = me->core_layout.base + me->arch.fdesc_offset;
Elf_Fdesc *fdesc = me->mem[MOD_TEXT].base + me->arch.fdesc_offset;
if (!value) {
printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
......@@ -407,7 +390,7 @@ static Elf_Addr get_fdesc(struct module *me, unsigned long value)
/* Create new one */
fdesc->addr = value;
fdesc->gp = (Elf_Addr)me->core_layout.base + me->arch.got_offset;
fdesc->gp = (Elf_Addr)me->mem[MOD_TEXT].base + me->arch.got_offset;
return (Elf_Addr)fdesc;
}
#endif /* CONFIG_64BIT */
......@@ -742,7 +725,7 @@ int apply_relocate_add(Elf_Shdr *sechdrs,
loc, val);
val += addend;
/* can we reach it locally? */
if (in_local(me, (void *)val)) {
if (within_module(val, me)) {
/* this is the case where the symbol is local
* to the module, but in a different section,
* so stub the jump in case it's more than 22
......@@ -801,7 +784,7 @@ int apply_relocate_add(Elf_Shdr *sechdrs,
break;
case R_PARISC_FPTR64:
/* 64-bit function address */
if(in_local(me, (void *)(val + addend))) {
if (within_module(val + addend, me)) {
*loc64 = get_fdesc(me, val+addend);
pr_debug("FDESC for %s at %llx points to %llx\n",
strtab + sym->st_name, *loc64,
......@@ -839,7 +822,7 @@ register_unwind_table(struct module *me,
table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
end = table + sechdrs[me->arch.unwind_section].sh_size;
gp = (Elf_Addr)me->core_layout.base + me->arch.got_offset;
gp = (Elf_Addr)me->mem[MOD_TEXT].base + me->arch.got_offset;
pr_debug("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
me->arch.unwind_section, table, end, gp);
......@@ -977,7 +960,7 @@ void module_arch_cleanup(struct module *mod)
#ifdef CONFIG_64BIT
void *dereference_module_function_descriptor(struct module *mod, void *ptr)
{
unsigned long start_opd = (Elf64_Addr)mod->core_layout.base +
unsigned long start_opd = (Elf64_Addr)mod->mem[MOD_TEXT].base +
mod->arch.fdesc_offset;
unsigned long end_opd = start_opd +
mod->arch.fdesc_count * sizeof(Elf64_Fdesc);
......
......@@ -163,8 +163,7 @@ static uint32_t do_plt_call(void *location,
pr_debug("Doing plt for call to 0x%x at 0x%x\n", val, (unsigned int)location);
/* Init, or core PLT? */
if (location >= mod->core_layout.base
&& location < mod->core_layout.base + mod->core_layout.size)
if (within_module_core((unsigned long)location, mod))
entry = (void *)sechdrs[mod->arch.core_plt_section].sh_addr;
else
entry = (void *)sechdrs[mod->arch.init_plt_section].sh_addr;
......@@ -322,14 +321,14 @@ notrace int module_trampoline_target(struct module *mod, unsigned long addr,
int module_finalize_ftrace(struct module *module, const Elf_Shdr *sechdrs)
{
module->arch.tramp = do_plt_call(module->core_layout.base,
module->arch.tramp = do_plt_call(module->mem[MOD_TEXT].base,
(unsigned long)ftrace_caller,
sechdrs, module);
if (!module->arch.tramp)
return -ENOENT;
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
module->arch.tramp_regs = do_plt_call(module->core_layout.base,
module->arch.tramp_regs = do_plt_call(module->mem[MOD_TEXT].base,
(unsigned long)ftrace_regs_caller,
sechdrs, module);
if (!module->arch.tramp_regs)
......
......@@ -126,6 +126,7 @@ int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
Elf_Rela *rela;
char *strings;
int nrela, i, j;
struct module_memory *mod_mem;
/* Find symbol table and string table. */
symtab = NULL;
......@@ -173,14 +174,15 @@ int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
/* Increase core size by size of got & plt and set start
offsets for got and plt. */
me->core_layout.size = ALIGN(me->core_layout.size, 4);
me->arch.got_offset = me->core_layout.size;
me->core_layout.size += me->arch.got_size;
me->arch.plt_offset = me->core_layout.size;
mod_mem = &me->mem[MOD_TEXT];
mod_mem->size = ALIGN(mod_mem->size, 4);
me->arch.got_offset = mod_mem->size;
mod_mem->size += me->arch.got_size;
me->arch.plt_offset = mod_mem->size;
if (me->arch.plt_size) {
if (IS_ENABLED(CONFIG_EXPOLINE) && !nospec_disable)
me->arch.plt_size += PLT_ENTRY_SIZE;
me->core_layout.size += me->arch.plt_size;
mod_mem->size += me->arch.plt_size;
}
return 0;
}
......@@ -304,7 +306,7 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
if (info->got_initialized == 0) {
Elf_Addr *gotent = me->core_layout.base +
Elf_Addr *gotent = me->mem[MOD_TEXT].base +
me->arch.got_offset +
info->got_offset;
......@@ -329,7 +331,7 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
rc = apply_rela_bits(loc, val, 0, 64, 0, write);
else if (r_type == R_390_GOTENT ||
r_type == R_390_GOTPLTENT) {
val += (Elf_Addr) me->core_layout.base - loc;
val += (Elf_Addr) me->mem[MOD_TEXT].base - loc;
rc = apply_rela_bits(loc, val, 1, 32, 1, write);
}
break;
......@@ -345,7 +347,7 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
char *plt_base;
char *ip;
plt_base = me->core_layout.base + me->arch.plt_offset;
plt_base = me->mem[MOD_TEXT].base + me->arch.plt_offset;
ip = plt_base + info->plt_offset;
*(int *)insn = 0x0d10e310; /* basr 1,0 */
*(int *)&insn[4] = 0x100c0004; /* lg 1,12(1) */
......@@ -375,7 +377,7 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
val - loc + 0xffffUL < 0x1ffffeUL) ||
(r_type == R_390_PLT32DBL &&
val - loc + 0xffffffffULL < 0x1fffffffeULL)))
val = (Elf_Addr) me->core_layout.base +
val = (Elf_Addr) me->mem[MOD_TEXT].base +
me->arch.plt_offset +
info->plt_offset;
val += rela->r_addend - loc;
......@@ -397,7 +399,7 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
case R_390_GOTOFF32: /* 32 bit offset to GOT. */
case R_390_GOTOFF64: /* 64 bit offset to GOT. */
val = val + rela->r_addend -
((Elf_Addr) me->core_layout.base + me->arch.got_offset);
((Elf_Addr) me->mem[MOD_TEXT].base + me->arch.got_offset);
if (r_type == R_390_GOTOFF16)
rc = apply_rela_bits(loc, val, 0, 16, 0, write);
else if (r_type == R_390_GOTOFF32)
......@@ -407,7 +409,7 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
break;
case R_390_GOTPC: /* 32 bit PC relative offset to GOT. */
case R_390_GOTPCDBL: /* 32 bit PC rel. off. to GOT shifted by 1. */
val = (Elf_Addr) me->core_layout.base + me->arch.got_offset +
val = (Elf_Addr) me->mem[MOD_TEXT].base + me->arch.got_offset +
rela->r_addend - loc;
if (r_type == R_390_GOTPC)
rc = apply_rela_bits(loc, val, 1, 32, 0, write);
......@@ -515,7 +517,7 @@ int module_finalize(const Elf_Ehdr *hdr,
!nospec_disable && me->arch.plt_size) {
unsigned int *ij;
ij = me->core_layout.base + me->arch.plt_offset +
ij = me->mem[MOD_TEXT].base + me->arch.plt_offset +
me->arch.plt_size - PLT_ENTRY_SIZE;
ij[0] = 0xc6000000; /* exrl %r0,.+10 */
ij[1] = 0x0005a7f4; /* j . */
......
......@@ -330,8 +330,8 @@ void noinline callthunks_patch_module_calls(struct callthunk_sites *cs,
struct module *mod)
{
struct core_text ct = {
.base = (unsigned long)mod->core_layout.base,
.end = (unsigned long)mod->core_layout.base + mod->core_layout.size,
.base = (unsigned long)mod->mem[MOD_TEXT].base,
.end = (unsigned long)mod->mem[MOD_TEXT].base + mod->mem[MOD_TEXT].size,
.name = mod->name,
};
......
......@@ -362,8 +362,8 @@ int module_finalize(const Elf_Ehdr *hdr,
}
if (locks) {
void *lseg = (void *)locks->sh_addr;
void *text = me->core_layout.base;
void *text_end = text + me->core_layout.text_size;
void *text = me->mem[MOD_TEXT].base;
void *text_end = text + me->mem[MOD_TEXT].size;
alternatives_smp_module_add(me, me->name,
lseg, lseg + locks->sh_size,
text, text_end);
......
......@@ -320,17 +320,47 @@ struct mod_tree_node {
struct latch_tree_node node;
};
struct module_layout {
/* The actual code + data. */
enum mod_mem_type {
MOD_TEXT = 0,
MOD_DATA,
MOD_RODATA,
MOD_RO_AFTER_INIT,
MOD_INIT_TEXT,
MOD_INIT_DATA,
MOD_INIT_RODATA,
MOD_MEM_NUM_TYPES,
MOD_INVALID = -1,
};
#define mod_mem_type_is_init(type) \
((type) == MOD_INIT_TEXT || \
(type) == MOD_INIT_DATA || \
(type) == MOD_INIT_RODATA)
#define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
#define mod_mem_type_is_text(type) \
((type) == MOD_TEXT || \
(type) == MOD_INIT_TEXT)
#define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
#define mod_mem_type_is_core_data(type) \
(mod_mem_type_is_core(type) && \
mod_mem_type_is_data(type))
#define for_each_mod_mem_type(type) \
for (enum mod_mem_type (type) = 0; \
(type) < MOD_MEM_NUM_TYPES; (type)++)
#define for_class_mod_mem_type(type, class) \
for_each_mod_mem_type(type) \
if (mod_mem_type_is_##class(type))
struct module_memory {
void *base;
/* Total size. */
unsigned int size;
/* The size of the executable code. */
unsigned int text_size;
/* Size of RO section of the module (text+rodata) */
unsigned int ro_size;
/* Size of RO after init section */
unsigned int ro_after_init_size;
#ifdef CONFIG_MODULES_TREE_LOOKUP
struct mod_tree_node mtn;
......@@ -339,9 +369,9 @@ struct module_layout {
#ifdef CONFIG_MODULES_TREE_LOOKUP
/* Only touch one cacheline for common rbtree-for-core-layout case. */
#define __module_layout_align ____cacheline_aligned
#define __module_memory_align ____cacheline_aligned
#else
#define __module_layout_align
#define __module_memory_align
#endif
struct mod_kallsyms {
......@@ -426,12 +456,7 @@ struct module {
/* Startup function. */
int (*init)(void);
/* Core layout: rbtree is accessed frequently, so keep together. */
struct module_layout core_layout __module_layout_align;
struct module_layout init_layout;
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
struct module_layout data_layout;
#endif
struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
/* Arch-specific module values */
struct mod_arch_specific arch;
......@@ -581,23 +606,35 @@ bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
bool is_module_percpu_address(unsigned long addr);
bool is_module_text_address(unsigned long addr);
static inline bool within_module_mem_type(unsigned long addr,
const struct module *mod,
enum mod_mem_type type)
{
unsigned long base, size;
base = (unsigned long)mod->mem[type].base;
size = mod->mem[type].size;
return addr - base < size;
}
static inline bool within_module_core(unsigned long addr,
const struct module *mod)
{
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
if ((unsigned long)mod->data_layout.base <= addr &&
addr < (unsigned long)mod->data_layout.base + mod->data_layout.size)
return true;
#endif
return (unsigned long)mod->core_layout.base <= addr &&
addr < (unsigned long)mod->core_layout.base + mod->core_layout.size;
for_class_mod_mem_type(type, core) {
if (within_module_mem_type(addr, mod, type))
return true;
}
return false;
}
static inline bool within_module_init(unsigned long addr,
const struct module *mod)
{
return (unsigned long)mod->init_layout.base <= addr &&
addr < (unsigned long)mod->init_layout.base + mod->init_layout.size;
for_class_mod_mem_type(type, init) {
if (within_module_mem_type(addr, mod, type))
return true;
}
return false;
}
static inline bool within_module(unsigned long addr, const struct module *mod)
......
......@@ -17,27 +17,19 @@
#define ARCH_SHF_SMALL 0
#endif
/* If this is set, the section belongs in the init part of the module */
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG - 1))
/* Maximum number of characters written by module_flags() */
#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
#ifndef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
#define data_layout core_layout
#endif
/*
* Modules' sections will be aligned on page boundaries
* to ensure complete separation of code and data, but
* only when CONFIG_STRICT_MODULE_RWX=y
* Use highest 4 bits of sh_entsize to store the mod_mem_type of this
* section. This leaves 28 bits for offset on 32-bit systems, which is
* about 256 MiB (WARN_ON_ONCE if we exceed that).
*/
static inline unsigned int strict_align(unsigned int size)
{
if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
return PAGE_ALIGN(size);
else
return size;
}
#define SH_ENTSIZE_TYPE_BITS 4
#define SH_ENTSIZE_TYPE_SHIFT (BITS_PER_LONG - SH_ENTSIZE_TYPE_BITS)
#define SH_ENTSIZE_TYPE_MASK ((1UL << SH_ENTSIZE_TYPE_BITS) - 1)
#define SH_ENTSIZE_OFFSET_MASK ((1UL << (BITS_PER_LONG - SH_ENTSIZE_TYPE_BITS)) - 1)
/* Maximum number of characters written by module_flags() */
#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
extern struct mutex module_mutex;
extern struct list_head modules;
......@@ -101,8 +93,8 @@ int try_to_force_load(struct module *mod, const char *reason);
bool find_symbol(struct find_symbol_arg *fsa);
struct module *find_module_all(const char *name, size_t len, bool even_unformed);
int cmp_name(const void *name, const void *sym);
long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr,
unsigned int section);
long module_get_offset_and_type(struct module *mod, enum mod_mem_type type,
Elf_Shdr *sechdr, unsigned int section);
char *module_flags(struct module *mod, char *buf, bool show_state);
size_t module_flags_taint(unsigned long taints, char *buf);
......@@ -190,10 +182,13 @@ struct mod_tree_root {
#endif
unsigned long addr_min;
unsigned long addr_max;
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
unsigned long data_addr_min;
unsigned long data_addr_max;
#endif
};
extern struct mod_tree_root mod_tree;
extern struct mod_tree_root mod_data_tree;
#ifdef CONFIG_MODULES_TREE_LOOKUP
void mod_tree_insert(struct module *mod);
......@@ -224,7 +219,6 @@ void module_enable_nx(const struct module *mod);
void module_enable_x(const struct module *mod);
int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
char *secstrings, struct module *mod);
bool module_check_misalignment(const struct module *mod);
#ifdef CONFIG_MODULE_SIG
int module_sig_check(struct load_info *info, int flags);
......
......@@ -78,6 +78,7 @@ static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
unsigned int shnum, unsigned int pcpundx)
{
const Elf_Shdr *sec;
enum mod_mem_type type;
if (src->st_shndx == SHN_UNDEF ||
src->st_shndx >= shnum ||
......@@ -90,11 +91,12 @@ static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
#endif
sec = sechdrs + src->st_shndx;
type = sec->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
if (!(sec->sh_flags & SHF_ALLOC)
#ifndef CONFIG_KALLSYMS_ALL
|| !(sec->sh_flags & SHF_EXECINSTR)
#endif
|| (sec->sh_entsize & INIT_OFFSET_MASK))
|| mod_mem_type_is_init(type))
return false;
return true;
......@@ -113,11 +115,13 @@ void layout_symtab(struct module *mod, struct load_info *info)
Elf_Shdr *strsect = info->sechdrs + info->index.str;
const Elf_Sym *src;
unsigned int i, nsrc, ndst, strtab_size = 0;
struct module_memory *mod_mem_data = &mod->mem[MOD_DATA];
struct module_memory *mod_mem_init_data = &mod->mem[MOD_INIT_DATA];
/* Put symbol section at end of init part of module. */
symsect->sh_flags |= SHF_ALLOC;
symsect->sh_entsize = module_get_offset(mod, &mod->init_layout.size, symsect,
info->index.sym) | INIT_OFFSET_MASK;
symsect->sh_entsize = module_get_offset_and_type(mod, MOD_INIT_DATA,
symsect, info->index.sym);
pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
src = (void *)info->hdr + symsect->sh_offset;
......@@ -134,28 +138,27 @@ void layout_symtab(struct module *mod, struct load_info *info)
}
/* Append room for core symbols at end of core part. */
info->symoffs = ALIGN(mod->data_layout.size, symsect->sh_addralign ?: 1);
info->stroffs = mod->data_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
mod->data_layout.size += strtab_size;
info->symoffs = ALIGN(mod_mem_data->size, symsect->sh_addralign ?: 1);
info->stroffs = mod_mem_data->size = info->symoffs + ndst * sizeof(Elf_Sym);
mod_mem_data->size += strtab_size;
/* Note add_kallsyms() computes strtab_size as core_typeoffs - stroffs */
info->core_typeoffs = mod->data_layout.size;
mod->data_layout.size += ndst * sizeof(char);
mod->data_layout.size = strict_align(mod->data_layout.size);
info->core_typeoffs = mod_mem_data->size;
mod_mem_data->size += ndst * sizeof(char);
/* Put string table section at end of init part of module. */
strsect->sh_flags |= SHF_ALLOC;
strsect->sh_entsize = module_get_offset(mod, &mod->init_layout.size, strsect,
info->index.str) | INIT_OFFSET_MASK;
strsect->sh_entsize = module_get_offset_and_type(mod, MOD_INIT_DATA,
strsect, info->index.str);
pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
/* We'll tack temporary mod_kallsyms on the end. */
mod->init_layout.size = ALIGN(mod->init_layout.size,
__alignof__(struct mod_kallsyms));
info->mod_kallsyms_init_off = mod->init_layout.size;
mod->init_layout.size += sizeof(struct mod_kallsyms);
info->init_typeoffs = mod->init_layout.size;
mod->init_layout.size += nsrc * sizeof(char);
mod->init_layout.size = strict_align(mod->init_layout.size);
mod_mem_init_data->size = ALIGN(mod_mem_init_data->size,
__alignof__(struct mod_kallsyms));
info->mod_kallsyms_init_off = mod_mem_init_data->size;
mod_mem_init_data->size += sizeof(struct mod_kallsyms);
info->init_typeoffs = mod_mem_init_data->size;
mod_mem_init_data->size += nsrc * sizeof(char);
}
/*
......@@ -171,9 +174,11 @@ void add_kallsyms(struct module *mod, const struct load_info *info)
char *s;
Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
unsigned long strtab_size;
void *data_base = mod->mem[MOD_DATA].base;
void *init_data_base = mod->mem[MOD_INIT_DATA].base;
/* Set up to point into init section. */
mod->kallsyms = (void __rcu *)mod->init_layout.base +
mod->kallsyms = (void __rcu *)init_data_base +
info->mod_kallsyms_init_off;
rcu_read_lock();
......@@ -183,15 +188,15 @@ void add_kallsyms(struct module *mod, const struct load_info *info)
/* Make sure we get permanent strtab: don't use info->strtab. */
rcu_dereference(mod->kallsyms)->strtab =
(void *)info->sechdrs[info->index.str].sh_addr;
rcu_dereference(mod->kallsyms)->typetab = mod->init_layout.base + info->init_typeoffs;
rcu_dereference(mod->kallsyms)->typetab = init_data_base + info->init_typeoffs;
/*
* Now populate the cut down core kallsyms for after init
* and set types up while we still have access to sections.
*/
mod->core_kallsyms.symtab = dst = mod->data_layout.base + info->symoffs;
mod->core_kallsyms.strtab = s = mod->data_layout.base + info->stroffs;
mod->core_kallsyms.typetab = mod->data_layout.base + info->core_typeoffs;
mod->core_kallsyms.symtab = dst = data_base + info->symoffs;
mod->core_kallsyms.strtab = s = data_base + info->stroffs;
mod->core_kallsyms.typetab = data_base + info->core_typeoffs;
strtab_size = info->core_typeoffs - info->stroffs;
src = rcu_dereference(mod->kallsyms)->symtab;
for (ndst = i = 0; i < rcu_dereference(mod->kallsyms)->num_symtab; i++) {
......@@ -267,12 +272,15 @@ static const char *find_kallsyms_symbol(struct module *mod,
unsigned int i, best = 0;
unsigned long nextval, bestval;
struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
struct module_memory *mod_mem;
/* At worse, next value is at end of module */
if (within_module_init(addr, mod))
nextval = (unsigned long)mod->init_layout.base + mod->init_layout.text_size;
mod_mem = &mod->mem[MOD_INIT_TEXT];
else
nextval = (unsigned long)mod->core_layout.base + mod->core_layout.text_size;
mod_mem = &mod->mem[MOD_TEXT];
nextval = (unsigned long)mod_mem->base + mod_mem->size;
bestval = kallsyms_symbol_value(&kallsyms->symtab[best]);
......
......@@ -26,10 +26,11 @@ int kdb_lsmod(int argc, const char **argv)
if (mod->state == MODULE_STATE_UNFORMED)
continue;
kdb_printf("%-20s%8u", mod->name, mod->core_layout.size);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
kdb_printf("/%8u", mod->data_layout.size);
#endif
kdb_printf("%-20s%8u", mod->name, mod->mem[MOD_TEXT].size);
kdb_printf("/%8u", mod->mem[MOD_RODATA].size);
kdb_printf("/%8u", mod->mem[MOD_RO_AFTER_INIT].size);
kdb_printf("/%8u", mod->mem[MOD_DATA].size);
kdb_printf(" 0x%px ", (void *)mod);
#ifdef CONFIG_MODULE_UNLOAD
kdb_printf("%4d ", module_refcount(mod));
......@@ -40,10 +41,10 @@ int kdb_lsmod(int argc, const char **argv)
kdb_printf(" (Loading)");
else
kdb_printf(" (Live)");
kdb_printf(" 0x%px", mod->core_layout.base);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
kdb_printf("/0x%px", mod->data_layout.base);
#endif
kdb_printf(" 0x%px", mod->mem[MOD_TEXT].base);
kdb_printf("/0x%px", mod->mem[MOD_RODATA].base);
kdb_printf("/0x%px", mod->mem[MOD_RO_AFTER_INIT].base);
kdb_printf("/0x%px", mod->mem[MOD_DATA].base);
#ifdef CONFIG_MODULE_UNLOAD
{
......
This diff is collapsed.
......@@ -62,6 +62,15 @@ static void m_stop(struct seq_file *m, void *p)
mutex_unlock(&module_mutex);
}
static unsigned int module_total_size(struct module *mod)
{
int size = 0;
for_each_mod_mem_type(type)
size += mod->mem[type].size;
return size;
}
static int m_show(struct seq_file *m, void *p)
{
struct module *mod = list_entry(p, struct module, list);
......@@ -73,10 +82,7 @@ static int m_show(struct seq_file *m, void *p)
if (mod->state == MODULE_STATE_UNFORMED)
return 0;
size = mod->init_layout.size + mod->core_layout.size;
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
size += mod->data_layout.size;
#endif
size = module_total_size(mod);
seq_printf(m, "%s %u", mod->name, size);
print_unload_info(m, mod);
......@@ -86,7 +92,7 @@ static int m_show(struct seq_file *m, void *p)
mod->state == MODULE_STATE_COMING ? "Loading" :
"Live");
/* Used by oprofile and other similar tools. */
value = m->private ? NULL : mod->core_layout.base;
value = m->private ? NULL : mod->mem[MOD_TEXT].base;
seq_printf(m, " 0x%px", value);
/* Taints info */
......
......@@ -11,82 +11,25 @@
#include <linux/set_memory.h>
#include "internal.h"
/*
* LKM RO/NX protection: protect module's text/ro-data
* from modification and any data from execution.
*
* General layout of module is:
* [text] [read-only-data] [ro-after-init] [writable data]
* text_size -----^ ^ ^ ^
* ro_size ------------------------| | |
* ro_after_init_size -----------------------------| |
* size -----------------------------------------------------------|
*
* These values are always page-aligned (as is base) when
* CONFIG_STRICT_MODULE_RWX is set.
*/
static void module_set_memory(const struct module *mod, enum mod_mem_type type,
int (*set_memory)(unsigned long start, int num_pages))
{
const struct module_memory *mod_mem = &mod->mem[type];
set_vm_flush_reset_perms(mod_mem->base);
set_memory((unsigned long)mod_mem->base, mod_mem->size >> PAGE_SHIFT);
}
/*
* Since some arches are moving towards PAGE_KERNEL module allocations instead
* of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() independent of
* of PAGE_KERNEL_EXEC, keep module_enable_x() independent of
* CONFIG_STRICT_MODULE_RWX because they are needed regardless of whether we
* are strict.
*/
static void frob_text(const struct module_layout *layout,
int (*set_memory)(unsigned long start, int num_pages))
{
set_memory((unsigned long)layout->base,
PAGE_ALIGN(layout->text_size) >> PAGE_SHIFT);
}
static void frob_rodata(const struct module_layout *layout,
int (*set_memory)(unsigned long start, int num_pages))
{
set_memory((unsigned long)layout->base + layout->text_size,
(layout->ro_size - layout->text_size) >> PAGE_SHIFT);
}
static void frob_ro_after_init(const struct module_layout *layout,
int (*set_memory)(unsigned long start, int num_pages))
{
set_memory((unsigned long)layout->base + layout->ro_size,
(layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT);
}
static void frob_writable_data(const struct module_layout *layout,
int (*set_memory)(unsigned long start, int num_pages))
{
set_memory((unsigned long)layout->base + layout->ro_after_init_size,
(layout->size - layout->ro_after_init_size) >> PAGE_SHIFT);
}
static bool layout_check_misalignment(const struct module_layout *layout)
{
return WARN_ON(!PAGE_ALIGNED(layout->base)) ||
WARN_ON(!PAGE_ALIGNED(layout->text_size)) ||
WARN_ON(!PAGE_ALIGNED(layout->ro_size)) ||
WARN_ON(!PAGE_ALIGNED(layout->ro_after_init_size)) ||
WARN_ON(!PAGE_ALIGNED(layout->size));
}
bool module_check_misalignment(const struct module *mod)
{
if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
return false;
return layout_check_misalignment(&mod->core_layout) ||
layout_check_misalignment(&mod->data_layout) ||
layout_check_misalignment(&mod->init_layout);
}
void module_enable_x(const struct module *mod)
{
if (!PAGE_ALIGNED(mod->core_layout.base) ||
!PAGE_ALIGNED(mod->init_layout.base))
return;
frob_text(&mod->core_layout, set_memory_x);
frob_text(&mod->init_layout, set_memory_x);
for_class_mod_mem_type(type, text)
module_set_memory(mod, type, set_memory_x);
}
void module_enable_ro(const struct module *mod, bool after_init)
......@@ -98,16 +41,13 @@ void module_enable_ro(const struct module *mod, bool after_init)
return;
#endif
set_vm_flush_reset_perms(mod->core_layout.base);
set_vm_flush_reset_perms(mod->init_layout.base);
frob_text(&mod->core_layout, set_memory_ro);
frob_rodata(&mod->data_layout, set_memory_ro);
frob_text(&mod->init_layout, set_memory_ro);
frob_rodata(&mod->init_layout, set_memory_ro);
module_set_memory(mod, MOD_TEXT, set_memory_ro);
module_set_memory(mod, MOD_INIT_TEXT, set_memory_ro);
module_set_memory(mod, MOD_RODATA, set_memory_ro);
module_set_memory(mod, MOD_INIT_RODATA, set_memory_ro);
if (after_init)
frob_ro_after_init(&mod->data_layout, set_memory_ro);
module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_ro);
}
void module_enable_nx(const struct module *mod)
......@@ -115,11 +55,8 @@ void module_enable_nx(const struct module *mod)
if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
return;
frob_rodata(&mod->data_layout, set_memory_nx);
frob_ro_after_init(&mod->data_layout, set_memory_nx);
frob_writable_data(&mod->data_layout, set_memory_nx);
frob_rodata(&mod->init_layout, set_memory_nx);
frob_writable_data(&mod->init_layout, set_memory_nx);
for_class_mod_mem_type(type, data)
module_set_memory(mod, type, set_memory_nx);
}
int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
......
......@@ -21,16 +21,16 @@
static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
{
struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
struct module_memory *mod_mem = container_of(n, struct module_memory, mtn.node);
return (unsigned long)layout->base;
return (unsigned long)mod_mem->base;
}
static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
{
struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
struct module_memory *mod_mem = container_of(n, struct module_memory, mtn.node);
return (unsigned long)layout->size;
return (unsigned long)mod_mem->size;
}
static __always_inline bool
......@@ -77,32 +77,27 @@ static void __mod_tree_remove(struct mod_tree_node *node, struct mod_tree_root *
*/
void mod_tree_insert(struct module *mod)
{
mod->core_layout.mtn.mod = mod;
mod->init_layout.mtn.mod = mod;
__mod_tree_insert(&mod->core_layout.mtn, &mod_tree);
if (mod->init_layout.size)
__mod_tree_insert(&mod->init_layout.mtn, &mod_tree);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
mod->data_layout.mtn.mod = mod;
__mod_tree_insert(&mod->data_layout.mtn, &mod_data_tree);
#endif
for_each_mod_mem_type(type) {
mod->mem[type].mtn.mod = mod;
if (mod->mem[type].size)
__mod_tree_insert(&mod->mem[type].mtn, &mod_tree);
}
}
void mod_tree_remove_init(struct module *mod)
{
if (mod->init_layout.size)
__mod_tree_remove(&mod->init_layout.mtn, &mod_tree);
for_class_mod_mem_type(type, init) {
if (mod->mem[type].size)
__mod_tree_remove(&mod->mem[type].mtn, &mod_tree);
}
}
void mod_tree_remove(struct module *mod)
{
__mod_tree_remove(&mod->core_layout.mtn, &mod_tree);
mod_tree_remove_init(mod);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
__mod_tree_remove(&mod->data_layout.mtn, &mod_data_tree);
#endif
for_each_mod_mem_type(type) {
if (mod->mem[type].size)
__mod_tree_remove(&mod->mem[type].mtn, &mod_tree);
}
}
struct module *mod_find(unsigned long addr, struct mod_tree_root *tree)
......
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