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module: replace module_layout with module_memory

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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: Song 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: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
This commit is contained in:
Song Liu 2023-02-06 16:28:02 -08:00 committed by Luis Chamberlain
parent fe15c26ee2
commit ac3b432839
18 changed files with 437 additions and 477 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

12
arch/arc/kernel/unwind.c
View file

@ -369,6 +369,8 @@ void *unwind_add_table(struct module *module, const void *table_start,
unsigned long table_size) unsigned long table_size)
{ {
struct unwind_table *table; struct unwind_table *table;
struct module_memory *core_text;
struct module_memory *init_text;
if (table_size <= 0) if (table_size <= 0)
return NULL; return NULL;
@ -377,11 +379,11 @@ void *unwind_add_table(struct module *module, const void *table_start,
if (!table) if (!table)
return NULL; return NULL;
init_unwind_table(table, module->name, core_text = &module->mem[MOD_TEXT];
module->core_layout.base, module->core_layout.size, init_text = &module->mem[MOD_INIT_TEXT];
module->init_layout.base, module->init_layout.size,
table_start, table_size, init_unwind_table(table, module->name, core_text->base, core_text->size,
NULL, 0); init_text->base, init_text->size, table_start, table_size, NULL, 0);
init_unwind_hdr(table, unw_hdr_alloc); init_unwind_hdr(table, unw_hdr_alloc);

9
arch/arm/kernel/module-plts.c
View file

@ -28,11 +28,6 @@ static const u32 fixed_plts[] = {
#endif #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) static void prealloc_fixed(struct mod_plt_sec *pltsec, struct plt_entries *plt)
{ {
int i; 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) 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 : struct mod_plt_sec *pltsec = !within_module_init(loc, mod) ?
&mod->arch.init; &mod->arch.core : &mod->arch.init;
struct plt_entries *plt; struct plt_entries *plt;
int idx; int idx;

13
arch/arm64/kernel/module-plts.c
View file

@ -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))); (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, u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs,
void *loc, const Elf64_Rela *rela, void *loc, const Elf64_Rela *rela,
Elf64_Sym *sym) Elf64_Sym *sym)
{ {
struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core : struct mod_plt_sec *pltsec = !within_module_init((unsigned long)loc, mod) ?
&mod->arch.init; &mod->arch.core : &mod->arch.init;
struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr; struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr;
int i = pltsec->plt_num_entries; int i = pltsec->plt_num_entries;
int j = i - 1; 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, u64 module_emit_veneer_for_adrp(struct module *mod, Elf64_Shdr *sechdrs,
void *loc, u64 val) void *loc, u64 val)
{ {
struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core : struct mod_plt_sec *pltsec = !within_module_init((unsigned long)loc, mod) ?
&mod->arch.init; &mod->arch.core : &mod->arch.init;
struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr; struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr;
int i = pltsec->plt_num_entries++; int i = pltsec->plt_num_entries++;
u32 br; u32 br;

24
arch/ia64/kernel/module.c
View file

@ -485,19 +485,19 @@ module_frob_arch_sections (Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, char *secstrings,
return 0; return 0;
} }
static inline int static inline bool
in_init (const struct module *mod, uint64_t addr) 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) 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) is_internal (const struct module *mod, uint64_t value)
{ {
return in_init(mod, value) || in_core(mod, 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; break;
case RV_BDREL: 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; break;
case RV_LTV: case RV_LTV:
@ -812,15 +813,18 @@ apply_relocate_add (Elf64_Shdr *sechdrs, const char *strtab, unsigned int symind
* addresses have been selected... * addresses have been selected...
*/ */
uint64_t gp; 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 * This takes advantage of fact that SHF_ARCH_SMALL gets allocated
* at the end of the module. * at the end of the module.
*/ */
gp = mod->core_layout.size - MAX_LTOFF / 2; gp = mod_mem->size - MAX_LTOFF / 2;
else else
gp = mod->core_layout.size / 2; gp = mod_mem->size / 2;
gp = (uint64_t) mod->core_layout.base + ((gp + 7) & -8); gp = (uint64_t) mod_mem->base + ((gp + 7) & -8);
mod->arch.gp = gp; mod->arch.gp = gp;
DEBUGP("%s: placing gp at 0x%lx\n", __func__, gp); DEBUGP("%s: placing gp at 0x%lx\n", __func__, gp);
} }

11
arch/mips/kernel/vpe.c
View file

@ -199,18 +199,17 @@ static void layout_sections(struct module *mod, const Elf_Ehdr *hdr,
for (m = 0; m < ARRAY_SIZE(masks); ++m) { for (m = 0; m < ARRAY_SIZE(masks); ++m) {
for (i = 0; i < hdr->e_shnum; ++i) { for (i = 0; i < hdr->e_shnum; ++i) {
Elf_Shdr *s = &sechdrs[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] if ((s->sh_flags & masks[m][0]) != masks[m][0]
|| (s->sh_flags & masks[m][1]) || (s->sh_flags & masks[m][1])
|| s->sh_entsize != ~0UL) || s->sh_entsize != ~0UL)
continue; continue;
s->sh_entsize = 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); 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) if (!v->load_addr)
return -ENOMEM; return -ENOMEM;

51
arch/parisc/kernel/module.c
View file

@ -27,9 +27,9 @@
* We are not doing SEGREL32 handling correctly. According to the ABI, we * We are not doing SEGREL32 handling correctly. According to the ABI, we
* should do a value offset, like this: * should do a value offset, like this:
* if (in_init(me, (void *)val)) * if (in_init(me, (void *)val))
* val -= (uint32_t)me->init_layout.base; * val -= (uint32_t)me->mem[MOD_INIT_TEXT].base;
* else * 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 * However, SEGREL32 is used only for PARISC unwind entries, and we want
* those entries to have an absolute address, and not just an offset. * 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. */ * allows us to allocate up to 4095 GOT entries. */
#define MAX_GOTS 4095 #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 #ifndef CONFIG_64BIT
struct got_entry { struct got_entry {
Elf32_Addr addr; Elf32_Addr addr;
@ -302,6 +283,7 @@ int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
{ {
unsigned long gots = 0, fdescs = 0, len; unsigned long gots = 0, fdescs = 0, len;
unsigned int i; unsigned int i;
struct module_memory *mod_mem;
len = hdr->e_shnum * sizeof(me->arch.section[0]); len = hdr->e_shnum * sizeof(me->arch.section[0]);
me->arch.section = kzalloc(len, GFP_KERNEL); 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; me->arch.section[s].stub_entries += count;
} }
mod_mem = &me->mem[MOD_TEXT];
/* align things a bit */ /* align things a bit */
me->core_layout.size = ALIGN(me->core_layout.size, 16); mod_mem->size = ALIGN(mod_mem->size, 16);
me->arch.got_offset = me->core_layout.size; me->arch.got_offset = mod_mem->size;
me->core_layout.size += gots * sizeof(struct got_entry); mod_mem->size += gots * sizeof(struct got_entry);
me->core_layout.size = ALIGN(me->core_layout.size, 16); mod_mem->size = ALIGN(mod_mem->size, 16);
me->arch.fdesc_offset = me->core_layout.size; me->arch.fdesc_offset = mod_mem->size;
me->core_layout.size += fdescs * sizeof(Elf_Fdesc); mod_mem->size += fdescs * sizeof(Elf_Fdesc);
me->arch.got_max = gots; me->arch.got_max = gots;
me->arch.fdesc_max = fdescs; 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); 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++) for (i = 0; got[i].addr; i++)
if (got[i].addr == value) if (got[i].addr == value)
goto out; goto out;
@ -389,7 +372,7 @@ static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
#ifdef CONFIG_64BIT #ifdef CONFIG_64BIT
static Elf_Addr get_fdesc(struct module *me, unsigned long value) 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) { if (!value) {
printk(KERN_ERR "%s: zero OPD requested!\n", me->name); 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 */ /* Create new one */
fdesc->addr = value; 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; return (Elf_Addr)fdesc;
} }
#endif /* CONFIG_64BIT */ #endif /* CONFIG_64BIT */
@ -742,7 +725,7 @@ int apply_relocate_add(Elf_Shdr *sechdrs,
loc, val); loc, val);
val += addend; val += addend;
/* can we reach it locally? */ /* 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 /* this is the case where the symbol is local
* to the module, but in a different section, * to the module, but in a different section,
* so stub the jump in case it's more than 22 * so stub the jump in case it's more than 22
@ -801,7 +784,7 @@ int apply_relocate_add(Elf_Shdr *sechdrs,
break; break;
case R_PARISC_FPTR64: case R_PARISC_FPTR64:
/* 64-bit function address */ /* 64-bit function address */
if(in_local(me, (void *)(val + addend))) { if (within_module(val + addend, me)) {
*loc64 = get_fdesc(me, val+addend); *loc64 = get_fdesc(me, val+addend);
pr_debug("FDESC for %s at %llx points to %llx\n", pr_debug("FDESC for %s at %llx points to %llx\n",
strtab + sym->st_name, *loc64, 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; table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
end = table + sechdrs[me->arch.unwind_section].sh_size; 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", pr_debug("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
me->arch.unwind_section, table, end, gp); me->arch.unwind_section, table, end, gp);
@ -977,7 +960,7 @@ void module_arch_cleanup(struct module *mod)
#ifdef CONFIG_64BIT #ifdef CONFIG_64BIT
void *dereference_module_function_descriptor(struct module *mod, void *ptr) 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; mod->arch.fdesc_offset;
unsigned long end_opd = start_opd + unsigned long end_opd = start_opd +
mod->arch.fdesc_count * sizeof(Elf64_Fdesc); mod->arch.fdesc_count * sizeof(Elf64_Fdesc);

7
arch/powerpc/kernel/module_32.c
View file

@ -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); pr_debug("Doing plt for call to 0x%x at 0x%x\n", val, (unsigned int)location);
/* Init, or core PLT? */ /* Init, or core PLT? */
if (location >= mod->core_layout.base if (within_module_core((unsigned long)location, mod))
&& location < mod->core_layout.base + mod->core_layout.size)
entry = (void *)sechdrs[mod->arch.core_plt_section].sh_addr; entry = (void *)sechdrs[mod->arch.core_plt_section].sh_addr;
else else
entry = (void *)sechdrs[mod->arch.init_plt_section].sh_addr; 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) 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, (unsigned long)ftrace_caller,
sechdrs, module); sechdrs, module);
if (!module->arch.tramp) if (!module->arch.tramp)
return -ENOENT; return -ENOENT;
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS #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, (unsigned long)ftrace_regs_caller,
sechdrs, module); sechdrs, module);
if (!module->arch.tramp_regs) if (!module->arch.tramp_regs)

26
arch/s390/kernel/module.c
View file

@ -126,6 +126,7 @@ int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
Elf_Rela *rela; Elf_Rela *rela;
char *strings; char *strings;
int nrela, i, j; int nrela, i, j;
struct module_memory *mod_mem;
/* Find symbol table and string table. */ /* Find symbol table and string table. */
symtab = NULL; 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 /* Increase core size by size of got & plt and set start
offsets for got and plt. */ offsets for got and plt. */
me->core_layout.size = ALIGN(me->core_layout.size, 4); mod_mem = &me->mem[MOD_TEXT];
me->arch.got_offset = me->core_layout.size; mod_mem->size = ALIGN(mod_mem->size, 4);
me->core_layout.size += me->arch.got_size; me->arch.got_offset = mod_mem->size;
me->arch.plt_offset = me->core_layout.size; mod_mem->size += me->arch.got_size;
me->arch.plt_offset = mod_mem->size;
if (me->arch.plt_size) { if (me->arch.plt_size) {
if (IS_ENABLED(CONFIG_EXPOLINE) && !nospec_disable) if (IS_ENABLED(CONFIG_EXPOLINE) && !nospec_disable)
me->arch.plt_size += PLT_ENTRY_SIZE; me->arch.plt_size += PLT_ENTRY_SIZE;
me->core_layout.size += me->arch.plt_size; mod_mem->size += me->arch.plt_size;
} }
return 0; 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_GOTPLT64: /* 64 bit offset to jump slot. */
case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */ case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
if (info->got_initialized == 0) { if (info->got_initialized == 0) {
Elf_Addr *gotent = me->core_layout.base + Elf_Addr *gotent = me->mem[MOD_TEXT].base +
me->arch.got_offset + me->arch.got_offset +
info->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); rc = apply_rela_bits(loc, val, 0, 64, 0, write);
else if (r_type == R_390_GOTENT || else if (r_type == R_390_GOTENT ||
r_type == R_390_GOTPLTENT) { 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); rc = apply_rela_bits(loc, val, 1, 32, 1, write);
} }
break; break;
@ -345,7 +347,7 @@ static int apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
char *plt_base; char *plt_base;
char *ip; 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; ip = plt_base + info->plt_offset;
*(int *)insn = 0x0d10e310; /* basr 1,0 */ *(int *)insn = 0x0d10e310; /* basr 1,0 */
*(int *)&insn[4] = 0x100c0004; /* lg 1,12(1) */ *(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) || val - loc + 0xffffUL < 0x1ffffeUL) ||
(r_type == R_390_PLT32DBL && (r_type == R_390_PLT32DBL &&
val - loc + 0xffffffffULL < 0x1fffffffeULL))) val - loc + 0xffffffffULL < 0x1fffffffeULL)))
val = (Elf_Addr) me->core_layout.base + val = (Elf_Addr) me->mem[MOD_TEXT].base +
me->arch.plt_offset + me->arch.plt_offset +
info->plt_offset; info->plt_offset;
val += rela->r_addend - loc; 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_GOTOFF32: /* 32 bit offset to GOT. */
case R_390_GOTOFF64: /* 64 bit offset to GOT. */ case R_390_GOTOFF64: /* 64 bit offset to GOT. */
val = val + rela->r_addend - 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) if (r_type == R_390_GOTOFF16)
rc = apply_rela_bits(loc, val, 0, 16, 0, write); rc = apply_rela_bits(loc, val, 0, 16, 0, write);
else if (r_type == R_390_GOTOFF32) 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; break;
case R_390_GOTPC: /* 32 bit PC relative offset to GOT. */ 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. */ 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; rela->r_addend - loc;
if (r_type == R_390_GOTPC) if (r_type == R_390_GOTPC)
rc = apply_rela_bits(loc, val, 1, 32, 0, write); 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) { !nospec_disable && me->arch.plt_size) {
unsigned int *ij; 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; me->arch.plt_size - PLT_ENTRY_SIZE;
ij[0] = 0xc6000000; /* exrl %r0,.+10 */ ij[0] = 0xc6000000; /* exrl %r0,.+10 */
ij[1] = 0x0005a7f4; /* j . */ ij[1] = 0x0005a7f4; /* j . */

4
arch/x86/kernel/callthunks.c
View file

@ -330,8 +330,8 @@ void noinline callthunks_patch_module_calls(struct callthunk_sites *cs,
struct module *mod) struct module *mod)
{ {
struct core_text ct = { struct core_text ct = {
.base = (unsigned long)mod->core_layout.base, .base = (unsigned long)mod->mem[MOD_TEXT].base,
.end = (unsigned long)mod->core_layout.base + mod->core_layout.size, .end = (unsigned long)mod->mem[MOD_TEXT].base + mod->mem[MOD_TEXT].size,
.name = mod->name, .name = mod->name,
}; };

4
arch/x86/kernel/module.c
View file

@ -362,8 +362,8 @@ int module_finalize(const Elf_Ehdr *hdr,
} }
if (locks) { if (locks) {
void *lseg = (void *)locks->sh_addr; void *lseg = (void *)locks->sh_addr;
void *text = me->core_layout.base; void *text = me->mem[MOD_TEXT].base;
void *text_end = text + me->core_layout.text_size; void *text_end = text + me->mem[MOD_TEXT].size;
alternatives_smp_module_add(me, me->name, alternatives_smp_module_add(me, me->name,
lseg, lseg + locks->sh_size, lseg, lseg + locks->sh_size,
text, text_end); text, text_end);

87
include/linux/module.h
View file

@ -320,17 +320,47 @@ struct mod_tree_node {
struct latch_tree_node node; struct latch_tree_node node;
}; };
struct module_layout { enum mod_mem_type {
/* The actual code + data. */ 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; void *base;
/* Total size. */
unsigned int 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 #ifdef CONFIG_MODULES_TREE_LOOKUP
struct mod_tree_node mtn; struct mod_tree_node mtn;
@ -339,9 +369,9 @@ struct module_layout {
#ifdef CONFIG_MODULES_TREE_LOOKUP #ifdef CONFIG_MODULES_TREE_LOOKUP
/* Only touch one cacheline for common rbtree-for-core-layout case. */ /* Only touch one cacheline for common rbtree-for-core-layout case. */
#define __module_layout_align ____cacheline_aligned #define __module_memory_align ____cacheline_aligned
#else #else
#define __module_layout_align #define __module_memory_align
#endif #endif
struct mod_kallsyms { struct mod_kallsyms {
@ -426,12 +456,7 @@ struct module {
/* Startup function. */ /* Startup function. */
int (*init)(void); int (*init)(void);
/* Core layout: rbtree is accessed frequently, so keep together. */ struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
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
/* Arch-specific module values */ /* Arch-specific module values */
struct mod_arch_specific arch; 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_percpu_address(unsigned long addr);
bool is_module_text_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, static inline bool within_module_core(unsigned long addr,
const struct module *mod) const struct module *mod)
{ {
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC for_class_mod_mem_type(type, core) {
if ((unsigned long)mod->data_layout.base <= addr && if (within_module_mem_type(addr, mod, type))
addr < (unsigned long)mod->data_layout.base + mod->data_layout.size)
return true; return true;
#endif }
return (unsigned long)mod->core_layout.base <= addr && return false;
addr < (unsigned long)mod->core_layout.base + mod->core_layout.size;
} }
static inline bool within_module_init(unsigned long addr, static inline bool within_module_init(unsigned long addr,
const struct module *mod) const struct module *mod)
{ {
return (unsigned long)mod->init_layout.base <= addr && for_class_mod_mem_type(type, init) {
addr < (unsigned long)mod->init_layout.base + mod->init_layout.size; if (within_module_mem_type(addr, mod, type))
return true;
}
return false;
} }
static inline bool within_module(unsigned long addr, const struct module *mod) static inline bool within_module(unsigned long addr, const struct module *mod)

40
kernel/module/internal.h
View file

@ -17,28 +17,20 @@
#define ARCH_SHF_SMALL 0 #define ARCH_SHF_SMALL 0
#endif #endif
/* If this is set, the section belongs in the init part of the module */ /*
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG - 1)) * 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).
*/
#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() */ /* Maximum number of characters written by module_flags() */
#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) #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
*/
static inline unsigned int strict_align(unsigned int size)
{
if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
return PAGE_ALIGN(size);
else
return size;
}
extern struct mutex module_mutex; extern struct mutex module_mutex;
extern struct list_head modules; 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); bool find_symbol(struct find_symbol_arg *fsa);
struct module *find_module_all(const char *name, size_t len, bool even_unformed); struct module *find_module_all(const char *name, size_t len, bool even_unformed);
int cmp_name(const void *name, const void *sym); int cmp_name(const void *name, const void *sym);
long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr, long module_get_offset_and_type(struct module *mod, enum mod_mem_type type,
unsigned int section); Elf_Shdr *sechdr, unsigned int section);
char *module_flags(struct module *mod, char *buf, bool show_state); char *module_flags(struct module *mod, char *buf, bool show_state);
size_t module_flags_taint(unsigned long taints, char *buf); size_t module_flags_taint(unsigned long taints, char *buf);
@ -190,10 +182,13 @@ struct mod_tree_root {
#endif #endif
unsigned long addr_min; unsigned long addr_min;
unsigned long addr_max; 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_tree;
extern struct mod_tree_root mod_data_tree;
#ifdef CONFIG_MODULES_TREE_LOOKUP #ifdef CONFIG_MODULES_TREE_LOOKUP
void mod_tree_insert(struct module *mod); 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); void module_enable_x(const struct module *mod);
int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
char *secstrings, struct module *mod); char *secstrings, struct module *mod);
bool module_check_misalignment(const struct module *mod);
#ifdef CONFIG_MODULE_SIG #ifdef CONFIG_MODULE_SIG
int module_sig_check(struct load_info *info, int flags); int module_sig_check(struct load_info *info, int flags);

56
kernel/module/kallsyms.c
View file

@ -78,6 +78,7 @@ static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
unsigned int shnum, unsigned int pcpundx) unsigned int shnum, unsigned int pcpundx)
{ {
const Elf_Shdr *sec; const Elf_Shdr *sec;
enum mod_mem_type type;
if (src->st_shndx == SHN_UNDEF || if (src->st_shndx == SHN_UNDEF ||
src->st_shndx >= shnum || src->st_shndx >= shnum ||
@ -90,11 +91,12 @@ static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
#endif #endif
sec = sechdrs + src->st_shndx; sec = sechdrs + src->st_shndx;
type = sec->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
if (!(sec->sh_flags & SHF_ALLOC) if (!(sec->sh_flags & SHF_ALLOC)
#ifndef CONFIG_KALLSYMS_ALL #ifndef CONFIG_KALLSYMS_ALL
|| !(sec->sh_flags & SHF_EXECINSTR) || !(sec->sh_flags & SHF_EXECINSTR)
#endif #endif
|| (sec->sh_entsize & INIT_OFFSET_MASK)) || mod_mem_type_is_init(type))
return false; return false;
return true; return true;
@ -113,11 +115,13 @@ void layout_symtab(struct module *mod, struct load_info *info)
Elf_Shdr *strsect = info->sechdrs + info->index.str; Elf_Shdr *strsect = info->sechdrs + info->index.str;
const Elf_Sym *src; const Elf_Sym *src;
unsigned int i, nsrc, ndst, strtab_size = 0; 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. */ /* Put symbol section at end of init part of module. */
symsect->sh_flags |= SHF_ALLOC; symsect->sh_flags |= SHF_ALLOC;
symsect->sh_entsize = module_get_offset(mod, &mod->init_layout.size, symsect, symsect->sh_entsize = module_get_offset_and_type(mod, MOD_INIT_DATA,
info->index.sym) | INIT_OFFSET_MASK; symsect, info->index.sym);
pr_debug("\t%s\n", info->secstrings + symsect->sh_name); pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
src = (void *)info->hdr + symsect->sh_offset; 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. */ /* Append room for core symbols at end of core part. */
info->symoffs = ALIGN(mod->data_layout.size, symsect->sh_addralign ?: 1); info->symoffs = ALIGN(mod_mem_data->size, symsect->sh_addralign ?: 1);
info->stroffs = mod->data_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); info->stroffs = mod_mem_data->size = info->symoffs + ndst * sizeof(Elf_Sym);
mod->data_layout.size += strtab_size; mod_mem_data->size += strtab_size;
/* Note add_kallsyms() computes strtab_size as core_typeoffs - stroffs */ /* Note add_kallsyms() computes strtab_size as core_typeoffs - stroffs */
info->core_typeoffs = mod->data_layout.size; info->core_typeoffs = mod_mem_data->size;
mod->data_layout.size += ndst * sizeof(char); mod_mem_data->size += ndst * sizeof(char);
mod->data_layout.size = strict_align(mod->data_layout.size);
/* Put string table section at end of init part of module. */ /* Put string table section at end of init part of module. */
strsect->sh_flags |= SHF_ALLOC; strsect->sh_flags |= SHF_ALLOC;
strsect->sh_entsize = module_get_offset(mod, &mod->init_layout.size, strsect, strsect->sh_entsize = module_get_offset_and_type(mod, MOD_INIT_DATA,
info->index.str) | INIT_OFFSET_MASK; strsect, info->index.str);
pr_debug("\t%s\n", info->secstrings + strsect->sh_name); pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
/* We'll tack temporary mod_kallsyms on the end. */ /* We'll tack temporary mod_kallsyms on the end. */
mod->init_layout.size = ALIGN(mod->init_layout.size, mod_mem_init_data->size = ALIGN(mod_mem_init_data->size,
__alignof__(struct mod_kallsyms)); __alignof__(struct mod_kallsyms));
info->mod_kallsyms_init_off = mod->init_layout.size; info->mod_kallsyms_init_off = mod_mem_init_data->size;
mod->init_layout.size += sizeof(struct mod_kallsyms);
info->init_typeoffs = mod->init_layout.size; mod_mem_init_data->size += sizeof(struct mod_kallsyms);
mod->init_layout.size += nsrc * sizeof(char); info->init_typeoffs = mod_mem_init_data->size;
mod->init_layout.size = strict_align(mod->init_layout.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; char *s;
Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
unsigned long strtab_size; 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. */ /* 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; info->mod_kallsyms_init_off;
rcu_read_lock(); 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. */ /* Make sure we get permanent strtab: don't use info->strtab. */
rcu_dereference(mod->kallsyms)->strtab = rcu_dereference(mod->kallsyms)->strtab =
(void *)info->sechdrs[info->index.str].sh_addr; (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 * Now populate the cut down core kallsyms for after init
* and set types up while we still have access to sections. * 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.symtab = dst = data_base + info->symoffs;
mod->core_kallsyms.strtab = s = mod->data_layout.base + info->stroffs; mod->core_kallsyms.strtab = s = data_base + info->stroffs;
mod->core_kallsyms.typetab = mod->data_layout.base + info->core_typeoffs; mod->core_kallsyms.typetab = data_base + info->core_typeoffs;
strtab_size = info->core_typeoffs - info->stroffs; strtab_size = info->core_typeoffs - info->stroffs;
src = rcu_dereference(mod->kallsyms)->symtab; src = rcu_dereference(mod->kallsyms)->symtab;
for (ndst = i = 0; i < rcu_dereference(mod->kallsyms)->num_symtab; i++) { 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 int i, best = 0;
unsigned long nextval, bestval; unsigned long nextval, bestval;
struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
struct module_memory *mod_mem;
/* At worse, next value is at end of module */ /* At worse, next value is at end of module */
if (within_module_init(addr, mod)) 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 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]); bestval = kallsyms_symbol_value(&kallsyms->symtab[best]);

17
kernel/module/kdb.c
View file

@ -26,10 +26,11 @@ int kdb_lsmod(int argc, const char **argv)
if (mod->state == MODULE_STATE_UNFORMED) if (mod->state == MODULE_STATE_UNFORMED)
continue; continue;
kdb_printf("%-20s%8u", mod->name, mod->core_layout.size); kdb_printf("%-20s%8u", mod->name, mod->mem[MOD_TEXT].size);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC kdb_printf("/%8u", mod->mem[MOD_RODATA].size);
kdb_printf("/%8u", mod->data_layout.size); kdb_printf("/%8u", mod->mem[MOD_RO_AFTER_INIT].size);
#endif kdb_printf("/%8u", mod->mem[MOD_DATA].size);
kdb_printf(" 0x%px ", (void *)mod); kdb_printf(" 0x%px ", (void *)mod);
#ifdef CONFIG_MODULE_UNLOAD #ifdef CONFIG_MODULE_UNLOAD
kdb_printf("%4d ", module_refcount(mod)); kdb_printf("%4d ", module_refcount(mod));
@ -40,10 +41,10 @@ int kdb_lsmod(int argc, const char **argv)
kdb_printf(" (Loading)"); kdb_printf(" (Loading)");
else else
kdb_printf(" (Live)"); kdb_printf(" (Live)");
kdb_printf(" 0x%px", mod->core_layout.base); kdb_printf(" 0x%px", mod->mem[MOD_TEXT].base);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC kdb_printf("/0x%px", mod->mem[MOD_RODATA].base);
kdb_printf("/0x%px", mod->data_layout.base); kdb_printf("/0x%px", mod->mem[MOD_RO_AFTER_INIT].base);
#endif kdb_printf("/0x%px", mod->mem[MOD_DATA].base);
#ifdef CONFIG_MODULE_UNLOAD #ifdef CONFIG_MODULE_UNLOAD
{ {

385
kernel/module/main.c
View file

@ -80,12 +80,6 @@ struct mod_tree_root mod_tree __cacheline_aligned = {
.addr_min = -1UL, .addr_min = -1UL,
}; };
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
struct mod_tree_root mod_data_tree __cacheline_aligned = {
.addr_min = -1UL,
};
#endif
struct symsearch { struct symsearch {
const struct kernel_symbol *start, *stop; const struct kernel_symbol *start, *stop;
const s32 *crcs; const s32 *crcs;
@ -93,14 +87,24 @@ struct symsearch {
}; };
/* /*
* Bounds of module text, for speeding up __module_address. * Bounds of module memory, for speeding up __module_address.
* Protected by module_mutex. * Protected by module_mutex.
*/ */
static void __mod_update_bounds(void *base, unsigned int size, struct mod_tree_root *tree) static void __mod_update_bounds(enum mod_mem_type type __maybe_unused, void *base,
unsigned int size, struct mod_tree_root *tree)
{ {
unsigned long min = (unsigned long)base; unsigned long min = (unsigned long)base;
unsigned long max = min + size; unsigned long max = min + size;
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
if (mod_mem_type_is_core_data(type)) {
if (min < tree->data_addr_min)
tree->data_addr_min = min;
if (max > tree->data_addr_max)
tree->data_addr_max = max;
return;
}
#endif
if (min < tree->addr_min) if (min < tree->addr_min)
tree->addr_min = min; tree->addr_min = min;
if (max > tree->addr_max) if (max > tree->addr_max)
@ -109,12 +113,12 @@ static void __mod_update_bounds(void *base, unsigned int size, struct mod_tree_r
static void mod_update_bounds(struct module *mod) static void mod_update_bounds(struct module *mod)
{ {
__mod_update_bounds(mod->core_layout.base, mod->core_layout.size, &mod_tree); for_each_mod_mem_type(type) {
if (mod->init_layout.size) struct module_memory *mod_mem = &mod->mem[type];
__mod_update_bounds(mod->init_layout.base, mod->init_layout.size, &mod_tree);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC if (mod_mem->size)
__mod_update_bounds(mod->data_layout.base, mod->data_layout.size, &mod_data_tree); __mod_update_bounds(type, mod_mem->base, mod_mem->size, &mod_tree);
#endif }
} }
/* Block module loading/unloading? */ /* Block module loading/unloading? */
@ -926,7 +930,13 @@ struct module_attribute module_uevent =
static ssize_t show_coresize(struct module_attribute *mattr, static ssize_t show_coresize(struct module_attribute *mattr,
struct module_kobject *mk, char *buffer) struct module_kobject *mk, char *buffer)
{ {
return sprintf(buffer, "%u\n", mk->mod->core_layout.size); unsigned int size = mk->mod->mem[MOD_TEXT].size;
if (!IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC)) {
for_class_mod_mem_type(type, core_data)
size += mk->mod->mem[type].size;
}
return sprintf(buffer, "%u\n", size);
} }
static struct module_attribute modinfo_coresize = static struct module_attribute modinfo_coresize =
@ -936,7 +946,11 @@ static struct module_attribute modinfo_coresize =
static ssize_t show_datasize(struct module_attribute *mattr, static ssize_t show_datasize(struct module_attribute *mattr,
struct module_kobject *mk, char *buffer) struct module_kobject *mk, char *buffer)
{ {
return sprintf(buffer, "%u\n", mk->mod->data_layout.size); unsigned int size = 0;
for_class_mod_mem_type(type, core_data)
size += mk->mod->mem[type].size;
return sprintf(buffer, "%u\n", size);
} }
static struct module_attribute modinfo_datasize = static struct module_attribute modinfo_datasize =
@ -946,7 +960,11 @@ static struct module_attribute modinfo_datasize =
static ssize_t show_initsize(struct module_attribute *mattr, static ssize_t show_initsize(struct module_attribute *mattr,
struct module_kobject *mk, char *buffer) struct module_kobject *mk, char *buffer)
{ {
return sprintf(buffer, "%u\n", mk->mod->init_layout.size); unsigned int size = 0;
for_class_mod_mem_type(type, init)
size += mk->mod->mem[type].size;
return sprintf(buffer, "%u\n", size);
} }
static struct module_attribute modinfo_initsize = static struct module_attribute modinfo_initsize =
@ -1143,6 +1161,46 @@ void __weak module_arch_freeing_init(struct module *mod)
{ {
} }
static bool mod_mem_use_vmalloc(enum mod_mem_type type)
{
return IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC) &&
mod_mem_type_is_core_data(type);
}
static void *module_memory_alloc(unsigned int size, enum mod_mem_type type)
{
if (mod_mem_use_vmalloc(type))
return vzalloc(size);
return module_alloc(size);
}
static void module_memory_free(void *ptr, enum mod_mem_type type)
{
if (mod_mem_use_vmalloc(type))
vfree(ptr);
else
module_memfree(ptr);
}
static void free_mod_mem(struct module *mod)
{
for_each_mod_mem_type(type) {
struct module_memory *mod_mem = &mod->mem[type];
if (type == MOD_DATA)
continue;
/* Free lock-classes; relies on the preceding sync_rcu(). */
lockdep_free_key_range(mod_mem->base, mod_mem->size);
if (mod_mem->size)
module_memory_free(mod_mem->base, type);
}
/* MOD_DATA hosts mod, so free it at last */
lockdep_free_key_range(mod->mem[MOD_DATA].base, mod->mem[MOD_DATA].size);
module_memory_free(mod->mem[MOD_DATA].base, MOD_DATA);
}
/* Free a module, remove from lists, etc. */ /* Free a module, remove from lists, etc. */
static void free_module(struct module *mod) static void free_module(struct module *mod)
{ {
@ -1189,18 +1247,10 @@ static void free_module(struct module *mod)
/* This may be empty, but that's OK */ /* This may be empty, but that's OK */
module_arch_freeing_init(mod); module_arch_freeing_init(mod);
module_memfree(mod->init_layout.base);
kfree(mod->args); kfree(mod->args);
percpu_modfree(mod); percpu_modfree(mod);
/* Free lock-classes; relies on the preceding sync_rcu(). */ free_mod_mem(mod);
lockdep_free_key_range(mod->data_layout.base, mod->data_layout.size);
/* Finally, free the core (containing the module structure) */
module_memfree(mod->core_layout.base);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
vfree(mod->data_layout.base);
#endif
} }
void *__symbol_get(const char *symbol) void *__symbol_get(const char *symbol)
@ -1387,16 +1437,18 @@ unsigned int __weak arch_mod_section_prepend(struct module *mod,
return 0; return 0;
} }
/* Update size with this section: return offset. */ long module_get_offset_and_type(struct module *mod, enum mod_mem_type type,
long module_get_offset(struct module *mod, unsigned int *size,
Elf_Shdr *sechdr, unsigned int section) Elf_Shdr *sechdr, unsigned int section)
{ {
long ret; long offset;
long mask = ((unsigned long)(type) & SH_ENTSIZE_TYPE_MASK) << SH_ENTSIZE_TYPE_SHIFT;
*size += arch_mod_section_prepend(mod, section); mod->mem[type].size += arch_mod_section_prepend(mod, section);
ret = ALIGN(*size, sechdr->sh_addralign ?: 1); offset = ALIGN(mod->mem[type].size, sechdr->sh_addralign ?: 1);
*size = ret + sechdr->sh_size; mod->mem[type].size = offset + sechdr->sh_size;
return ret;
WARN_ON_ONCE(offset & mask);
return offset | mask;
} }
static bool module_init_layout_section(const char *sname) static bool module_init_layout_section(const char *sname)
@ -1408,15 +1460,11 @@ static bool module_init_layout_section(const char *sname)
return module_init_section(sname); return module_init_section(sname);
} }
/* static void __layout_sections(struct module *mod, struct load_info *info, bool is_init)
* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
* might -- code, read-only data, read-write data, small data. Tally
* sizes, and place the offsets into sh_entsize fields: high bit means it
* belongs in init.
*/
static void layout_sections(struct module *mod, struct load_info *info)
{ {
static unsigned long const masks[][2] = { unsigned int m, i;
static const unsigned long masks[][2] = {
/* /*
* NOTE: all executable code must be the first section * NOTE: all executable code must be the first section
* in this array; otherwise modify the text_size * in this array; otherwise modify the text_size
@ -1428,82 +1476,61 @@ static void layout_sections(struct module *mod, struct load_info *info)
{ SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
{ ARCH_SHF_SMALL | SHF_ALLOC, 0 } { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
}; };
unsigned int m, i; static const int core_m_to_mem_type[] = {
MOD_TEXT,
MOD_RODATA,
MOD_RO_AFTER_INIT,
MOD_DATA,
MOD_INVALID, /* This is needed to match the masks array */
};
static const int init_m_to_mem_type[] = {
MOD_INIT_TEXT,
MOD_INIT_RODATA,
MOD_INVALID,
MOD_INIT_DATA,
MOD_INVALID, /* This is needed to match the masks array */
};
for (m = 0; m < ARRAY_SIZE(masks); ++m) {
enum mod_mem_type type = is_init ? init_m_to_mem_type[m] : core_m_to_mem_type[m];
for (i = 0; i < info->hdr->e_shnum; ++i) {
Elf_Shdr *s = &info->sechdrs[i];
const char *sname = info->secstrings + s->sh_name;
if ((s->sh_flags & masks[m][0]) != masks[m][0]
|| (s->sh_flags & masks[m][1])
|| s->sh_entsize != ~0UL
|| is_init != module_init_layout_section(sname))
continue;
if (WARN_ON_ONCE(type == MOD_INVALID))
continue;
s->sh_entsize = module_get_offset_and_type(mod, type, s, i);
pr_debug("\t%s\n", sname);
}
}
}
/*
* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
* might -- code, read-only data, read-write data, small data. Tally
* sizes, and place the offsets into sh_entsize fields: high bit means it
* belongs in init.
*/
static void layout_sections(struct module *mod, struct load_info *info)
{
unsigned int i;
for (i = 0; i < info->hdr->e_shnum; i++) for (i = 0; i < info->hdr->e_shnum; i++)
info->sechdrs[i].sh_entsize = ~0UL; info->sechdrs[i].sh_entsize = ~0UL;
pr_debug("Core section allocation order:\n"); pr_debug("Core section allocation order:\n");
for (m = 0; m < ARRAY_SIZE(masks); ++m) { __layout_sections(mod, info, false);
for (i = 0; i < info->hdr->e_shnum; ++i) {
Elf_Shdr *s = &info->sechdrs[i];
const char *sname = info->secstrings + s->sh_name;
unsigned int *sizep;
if ((s->sh_flags & masks[m][0]) != masks[m][0]
|| (s->sh_flags & masks[m][1])
|| s->sh_entsize != ~0UL
|| module_init_layout_section(sname))
continue;
sizep = m ? &mod->data_layout.size : &mod->core_layout.size;
s->sh_entsize = module_get_offset(mod, sizep, s, i);
pr_debug("\t%s\n", sname);
}
switch (m) {
case 0: /* executable */
mod->core_layout.size = strict_align(mod->core_layout.size);
mod->core_layout.text_size = mod->core_layout.size;
break;
case 1: /* RO: text and ro-data */
mod->data_layout.size = strict_align(mod->data_layout.size);
mod->data_layout.ro_size = mod->data_layout.size;
break;
case 2: /* RO after init */
mod->data_layout.size = strict_align(mod->data_layout.size);
mod->data_layout.ro_after_init_size = mod->data_layout.size;
break;
case 4: /* whole core */
mod->data_layout.size = strict_align(mod->data_layout.size);
break;
}
}
pr_debug("Init section allocation order:\n"); pr_debug("Init section allocation order:\n");
for (m = 0; m < ARRAY_SIZE(masks); ++m) { __layout_sections(mod, info, true);
for (i = 0; i < info->hdr->e_shnum; ++i) {
Elf_Shdr *s = &info->sechdrs[i];
const char *sname = info->secstrings + s->sh_name;
if ((s->sh_flags & masks[m][0]) != masks[m][0]
|| (s->sh_flags & masks[m][1])
|| s->sh_entsize != ~0UL
|| !module_init_layout_section(sname))
continue;
s->sh_entsize = (module_get_offset(mod, &mod->init_layout.size, s, i)
| INIT_OFFSET_MASK);
pr_debug("\t%s\n", sname);
}
switch (m) {
case 0: /* executable */
mod->init_layout.size = strict_align(mod->init_layout.size);
mod->init_layout.text_size = mod->init_layout.size;
break;
case 1: /* RO: text and ro-data */
mod->init_layout.size = strict_align(mod->init_layout.size);
mod->init_layout.ro_size = mod->init_layout.size;
break;
case 2:
/*
* RO after init doesn't apply to init_layout (only
* core_layout), so it just takes the value of ro_size.
*/
mod->init_layout.ro_after_init_size = mod->init_layout.ro_size;
break;
case 4: /* whole init */
mod->init_layout.size = strict_align(mod->init_layout.size);
break;
}
}
} }
static void set_license(struct module *mod, const char *license) static void set_license(struct module *mod, const char *license)
@ -2122,72 +2149,41 @@ static int move_module(struct module *mod, struct load_info *info)
{ {
int i; int i;
void *ptr; void *ptr;
enum mod_mem_type t;
for_each_mod_mem_type(type) {
if (!mod->mem[type].size) {
mod->mem[type].base = NULL;
continue;
}
mod->mem[type].size = PAGE_ALIGN(mod->mem[type].size);
ptr = module_memory_alloc(mod->mem[type].size, type);
/* Do the allocs. */
ptr = module_alloc(mod->core_layout.size);
/* /*
* The pointer to this block is stored in the module structure * The pointer to this block is stored in the module structure
* which is inside the block. Just mark it as not being a * which is inside the block. Just mark it as not being a
* leak. * leak.
*/ */
kmemleak_not_leak(ptr);
if (!ptr)
return -ENOMEM;
memset(ptr, 0, mod->core_layout.size);
mod->core_layout.base = ptr;
if (mod->init_layout.size) {
ptr = module_alloc(mod->init_layout.size);
/*
* The pointer to this block is stored in the module structure
* which is inside the block. This block doesn't need to be
* scanned as it contains data and code that will be freed
* after the module is initialized.
*/
kmemleak_ignore(ptr); kmemleak_ignore(ptr);
if (!ptr) { if (!ptr) {
module_memfree(mod->core_layout.base); t = type;
return -ENOMEM; goto out_enomem;
} }
memset(ptr, 0, mod->init_layout.size); memset(ptr, 0, mod->mem[type].size);
mod->init_layout.base = ptr; mod->mem[type].base = ptr;
} else
mod->init_layout.base = NULL;
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
/* Do the allocs. */
ptr = vzalloc(mod->data_layout.size);
/*
* The pointer to this block is stored in the module structure
* which is inside the block. Just mark it as not being a
* leak.
*/
kmemleak_not_leak(ptr);
if (!ptr) {
module_memfree(mod->core_layout.base);
module_memfree(mod->init_layout.base);
return -ENOMEM;
} }
mod->data_layout.base = ptr;
#endif
/* Transfer each section which specifies SHF_ALLOC */ /* Transfer each section which specifies SHF_ALLOC */
pr_debug("final section addresses:\n"); pr_debug("final section addresses:\n");
for (i = 0; i < info->hdr->e_shnum; i++) { for (i = 0; i < info->hdr->e_shnum; i++) {
void *dest; void *dest;
Elf_Shdr *shdr = &info->sechdrs[i]; Elf_Shdr *shdr = &info->sechdrs[i];
enum mod_mem_type type = shdr->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
if (!(shdr->sh_flags & SHF_ALLOC)) if (!(shdr->sh_flags & SHF_ALLOC))
continue; continue;
if (shdr->sh_entsize & INIT_OFFSET_MASK) dest = mod->mem[type].base + (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK);
dest = mod->init_layout.base
+ (shdr->sh_entsize & ~INIT_OFFSET_MASK);
else if (!(shdr->sh_flags & SHF_EXECINSTR))
dest = mod->data_layout.base + shdr->sh_entsize;
else
dest = mod->core_layout.base + shdr->sh_entsize;
if (shdr->sh_type != SHT_NOBITS) if (shdr->sh_type != SHT_NOBITS)
memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
@ -2198,6 +2194,10 @@ static int move_module(struct module *mod, struct load_info *info)
} }
return 0; return 0;
out_enomem:
for (t--; t >= 0; t--)
module_memory_free(mod->mem[t].base, t);
return -ENOMEM;
} }
static int check_module_license_and_versions(struct module *mod) static int check_module_license_and_versions(struct module *mod)
@ -2242,12 +2242,14 @@ static void flush_module_icache(const struct module *mod)
* Do it before processing of module parameters, so the module * Do it before processing of module parameters, so the module
* can provide parameter accessor functions of its own. * can provide parameter accessor functions of its own.
*/ */
if (mod->init_layout.base) for_each_mod_mem_type(type) {
flush_icache_range((unsigned long)mod->init_layout.base, const struct module_memory *mod_mem = &mod->mem[type];
(unsigned long)mod->init_layout.base
+ mod->init_layout.size); if (mod_mem->size) {
flush_icache_range((unsigned long)mod->core_layout.base, flush_icache_range((unsigned long)mod_mem->base,
(unsigned long)mod->core_layout.base + mod->core_layout.size); (unsigned long)mod_mem->base + mod_mem->size);
}
}
} }
bool __weak module_elf_check_arch(Elf_Ehdr *hdr) bool __weak module_elf_check_arch(Elf_Ehdr *hdr)
@ -2350,11 +2352,8 @@ static void module_deallocate(struct module *mod, struct load_info *info)
{ {
percpu_modfree(mod); percpu_modfree(mod);
module_arch_freeing_init(mod); module_arch_freeing_init(mod);
module_memfree(mod->init_layout.base);
module_memfree(mod->core_layout.base); free_mod_mem(mod);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
vfree(mod->data_layout.base);
#endif
} }
int __weak module_finalize(const Elf_Ehdr *hdr, int __weak module_finalize(const Elf_Ehdr *hdr,
@ -2415,7 +2414,9 @@ static void do_mod_ctors(struct module *mod)
/* For freeing module_init on success, in case kallsyms traversing */ /* For freeing module_init on success, in case kallsyms traversing */
struct mod_initfree { struct mod_initfree {
struct llist_node node; struct llist_node node;
void *module_init; void *init_text;
void *init_data;
void *init_rodata;
}; };
static void do_free_init(struct work_struct *w) static void do_free_init(struct work_struct *w)
@ -2429,7 +2430,9 @@ static void do_free_init(struct work_struct *w)
llist_for_each_safe(pos, n, list) { llist_for_each_safe(pos, n, list) {
initfree = container_of(pos, struct mod_initfree, node); initfree = container_of(pos, struct mod_initfree, node);
module_memfree(initfree->module_init); module_memfree(initfree->init_text);
module_memfree(initfree->init_data);
module_memfree(initfree->init_rodata);
kfree(initfree); kfree(initfree);
} }
} }
@ -2456,7 +2459,9 @@ static noinline int do_init_module(struct module *mod)
ret = -ENOMEM; ret = -ENOMEM;
goto fail; goto fail;
} }
freeinit->module_init = mod->init_layout.base; freeinit->init_text = mod->mem[MOD_INIT_TEXT].base;
freeinit->init_data = mod->mem[MOD_INIT_DATA].base;
freeinit->init_rodata = mod->mem[MOD_INIT_RODATA].base;
do_mod_ctors(mod); do_mod_ctors(mod);
/* Start the module */ /* Start the module */
@ -2492,8 +2497,8 @@ static noinline int do_init_module(struct module *mod)
if (!mod->async_probe_requested) if (!mod->async_probe_requested)
async_synchronize_full(); async_synchronize_full();
ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base + ftrace_free_mem(mod, mod->mem[MOD_INIT_TEXT].base,
mod->init_layout.size); mod->mem[MOD_INIT_TEXT].base + mod->mem[MOD_INIT_TEXT].size);
mutex_lock(&module_mutex); mutex_lock(&module_mutex);
/* Drop initial reference. */ /* Drop initial reference. */
module_put(mod); module_put(mod);
@ -2505,11 +2510,10 @@ static noinline int do_init_module(struct module *mod)
module_enable_ro(mod, true); module_enable_ro(mod, true);
mod_tree_remove_init(mod); mod_tree_remove_init(mod);
module_arch_freeing_init(mod); module_arch_freeing_init(mod);
mod->init_layout.base = NULL; for_class_mod_mem_type(type, init) {
mod->init_layout.size = 0; mod->mem[type].base = NULL;
mod->init_layout.ro_size = 0; mod->mem[type].size = 0;
mod->init_layout.ro_after_init_size = 0; }
mod->init_layout.text_size = 0;
#ifdef CONFIG_DEBUG_INFO_BTF_MODULES #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
/* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */ /* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */
mod->btf_data = NULL; mod->btf_data = NULL;
@ -2628,9 +2632,6 @@ static int complete_formation(struct module *mod, struct load_info *info)
module_bug_finalize(info->hdr, info->sechdrs, mod); module_bug_finalize(info->hdr, info->sechdrs, mod);
module_cfi_finalize(info->hdr, info->sechdrs, mod); module_cfi_finalize(info->hdr, info->sechdrs, mod);
if (module_check_misalignment(mod))
goto out_misaligned;
module_enable_ro(mod, false); module_enable_ro(mod, false);
module_enable_nx(mod); module_enable_nx(mod);
module_enable_x(mod); module_enable_x(mod);
@ -2644,8 +2645,6 @@ static int complete_formation(struct module *mod, struct load_info *info)
return 0; return 0;
out_misaligned:
err = -EINVAL;
out: out:
mutex_unlock(&module_mutex); mutex_unlock(&module_mutex);
return err; return err;
@ -2909,7 +2908,10 @@ static int load_module(struct load_info *info, const char __user *uargs,
mutex_unlock(&module_mutex); mutex_unlock(&module_mutex);
free_module: free_module:
/* Free lock-classes; relies on the preceding sync_rcu() */ /* Free lock-classes; relies on the preceding sync_rcu() */
lockdep_free_key_range(mod->data_layout.base, mod->data_layout.size); for_class_mod_mem_type(type, core_data) {
lockdep_free_key_range(mod->mem[type].base,
mod->mem[type].size);
}
module_deallocate(mod, info); module_deallocate(mod, info);
free_copy: free_copy:
@ -3060,20 +3062,21 @@ bool is_module_address(unsigned long addr)
struct module *__module_address(unsigned long addr) struct module *__module_address(unsigned long addr)
{ {
struct module *mod; struct module *mod;
struct mod_tree_root *tree;
if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max) if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max)
tree = &mod_tree; goto lookup;
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC #ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
else if (addr >= mod_data_tree.addr_min && addr <= mod_data_tree.addr_max) if (addr >= mod_tree.data_addr_min && addr <= mod_tree.data_addr_max)
tree = &mod_data_tree; goto lookup;
#endif #endif
else
return NULL; return NULL;
lookup:
module_assert_mutex_or_preempt(); module_assert_mutex_or_preempt();
mod = mod_find(addr, tree); mod = mod_find(addr, &mod_tree);
if (mod) { if (mod) {
BUG_ON(!within_module(addr, mod)); BUG_ON(!within_module(addr, mod));
if (mod->state == MODULE_STATE_UNFORMED) if (mod->state == MODULE_STATE_UNFORMED)
@ -3113,8 +3116,8 @@ struct module *__module_text_address(unsigned long addr)
struct module *mod = __module_address(addr); struct module *mod = __module_address(addr);
if (mod) { if (mod) {
/* Make sure it's within the text section. */ /* Make sure it's within the text section. */
if (!within(addr, mod->init_layout.base, mod->init_layout.text_size) if (!within_module_mem_type(addr, mod, MOD_TEXT) &&
&& !within(addr, mod->core_layout.base, mod->core_layout.text_size)) !within_module_mem_type(addr, mod, MOD_INIT_TEXT))
mod = NULL; mod = NULL;
} }
return mod; return mod;

16
kernel/module/procfs.c
View file

@ -62,6 +62,15 @@ static void m_stop(struct seq_file *m, void *p)
mutex_unlock(&module_mutex); 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) static int m_show(struct seq_file *m, void *p)
{ {
struct module *mod = list_entry(p, struct module, list); 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) if (mod->state == MODULE_STATE_UNFORMED)
return 0; return 0;
size = mod->init_layout.size + mod->core_layout.size; size = module_total_size(mod);
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
size += mod->data_layout.size;
#endif
seq_printf(m, "%s %u", mod->name, size); seq_printf(m, "%s %u", mod->name, size);
print_unload_info(m, mod); 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" : mod->state == MODULE_STATE_COMING ? "Loading" :
"Live"); "Live");
/* Used by oprofile and other similar tools. */ /* 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); seq_printf(m, " 0x%px", value);
/* Taints info */ /* Taints info */

99
kernel/module/strict_rwx.c
View file

@ -11,82 +11,25 @@
#include <linux/set_memory.h> #include <linux/set_memory.h>
#include "internal.h" #include "internal.h"
/* static void module_set_memory(const struct module *mod, enum mod_mem_type type,
* LKM RO/NX protection: protect module's text/ro-data int (*set_memory)(unsigned long start, int num_pages))
* from modification and any data from execution. {
* const struct module_memory *mod_mem = &mod->mem[type];
* General layout of module is:
* [text] [read-only-data] [ro-after-init] [writable data] set_vm_flush_reset_perms(mod_mem->base);
* text_size -----^ ^ ^ ^ set_memory((unsigned long)mod_mem->base, mod_mem->size >> PAGE_SHIFT);
* ro_size ------------------------| | | }
* ro_after_init_size -----------------------------| |
* size -----------------------------------------------------------|
*
* These values are always page-aligned (as is base) when
* CONFIG_STRICT_MODULE_RWX is set.
*/
/* /*
* Since some arches are moving towards PAGE_KERNEL module allocations instead * 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 * CONFIG_STRICT_MODULE_RWX because they are needed regardless of whether we
* are strict. * 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) void module_enable_x(const struct module *mod)
{ {
if (!PAGE_ALIGNED(mod->core_layout.base) || for_class_mod_mem_type(type, text)
!PAGE_ALIGNED(mod->init_layout.base)) module_set_memory(mod, type, set_memory_x);
return;
frob_text(&mod->core_layout, set_memory_x);
frob_text(&mod->init_layout, set_memory_x);
} }
void module_enable_ro(const struct module *mod, bool after_init) 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; return;
#endif #endif
set_vm_flush_reset_perms(mod->core_layout.base); module_set_memory(mod, MOD_TEXT, set_memory_ro);
set_vm_flush_reset_perms(mod->init_layout.base); module_set_memory(mod, MOD_INIT_TEXT, set_memory_ro);
frob_text(&mod->core_layout, set_memory_ro); module_set_memory(mod, MOD_RODATA, set_memory_ro);
module_set_memory(mod, MOD_INIT_RODATA, 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);
if (after_init) 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) 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)) if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
return; return;
frob_rodata(&mod->data_layout, set_memory_nx); for_class_mod_mem_type(type, data)
frob_ro_after_init(&mod->data_layout, set_memory_nx); module_set_memory(mod, type, 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);
} }
int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,

39
kernel/module/tree_lookup.c
View file

@ -21,16 +21,16 @@
static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n) 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) 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 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) void mod_tree_insert(struct module *mod)
{ {
mod->core_layout.mtn.mod = mod; for_each_mod_mem_type(type) {
mod->init_layout.mtn.mod = mod; mod->mem[type].mtn.mod = mod;
if (mod->mem[type].size)
__mod_tree_insert(&mod->core_layout.mtn, &mod_tree); __mod_tree_insert(&mod->mem[type].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
} }
void mod_tree_remove_init(struct module *mod) void mod_tree_remove_init(struct module *mod)
{ {
if (mod->init_layout.size) for_class_mod_mem_type(type, init) {
__mod_tree_remove(&mod->init_layout.mtn, &mod_tree); if (mod->mem[type].size)
__mod_tree_remove(&mod->mem[type].mtn, &mod_tree);
}
} }
void mod_tree_remove(struct module *mod) void mod_tree_remove(struct module *mod)
{ {
__mod_tree_remove(&mod->core_layout.mtn, &mod_tree); for_each_mod_mem_type(type) {
mod_tree_remove_init(mod); if (mod->mem[type].size)
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC __mod_tree_remove(&mod->mem[type].mtn, &mod_tree);
__mod_tree_remove(&mod->data_layout.mtn, &mod_data_tree); }
#endif
} }
struct module *mod_find(unsigned long addr, struct mod_tree_root *tree) struct module *mod_find(unsigned long addr, struct mod_tree_root *tree)