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-rw-r--r--arch/mips/kernel/module.c301
1 files changed, 223 insertions, 78 deletions
diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c
index 977a623d9253..ba0f62d8eff5 100644
--- a/arch/mips/kernel/module.c
+++ b/arch/mips/kernel/module.c
@@ -1,17 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Copyright (C) 2001 Rusty Russell.
* Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org)
@@ -20,18 +8,18 @@
#undef DEBUG
+#include <linux/extable.h>
#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/mm.h>
-#include <linux/vmalloc.h>
+#include <linux/numa.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/jump_label.h>
-
-#include <asm/pgtable.h> /* MODULE_START */
+#include <asm/jump_label.h>
struct mips_hi16 {
struct mips_hi16 *next;
@@ -42,52 +30,43 @@ struct mips_hi16 {
static LIST_HEAD(dbe_list);
static DEFINE_SPINLOCK(dbe_lock);
-#ifdef MODULE_START
-void *module_alloc(unsigned long size)
+static void apply_r_mips_32(u32 *location, u32 base, Elf_Addr v)
{
- return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
- GFP_KERNEL, PAGE_KERNEL, -1,
- __builtin_return_address(0));
+ *location = base + v;
}
-#endif
-int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v)
-{
- return 0;
-}
-
-static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v)
-{
- *location += v;
-
- return 0;
-}
-
-static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_26(struct module *me, u32 *location, u32 base,
+ Elf_Addr v)
{
if (v % 4) {
- pr_err("module %s: dangerous R_MIPS_26 REL relocation\n",
+ pr_err("module %s: dangerous R_MIPS_26 relocation\n",
me->name);
return -ENOEXEC;
}
if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
- printk(KERN_ERR
- "module %s: relocation overflow\n",
+ pr_err("module %s: relocation overflow\n",
me->name);
return -ENOEXEC;
}
*location = (*location & ~0x03ffffff) |
- ((*location + (v >> 2)) & 0x03ffffff);
+ ((base + (v >> 2)) & 0x03ffffff);
return 0;
}
-static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_hi16(struct module *me, u32 *location, Elf_Addr v,
+ bool rela)
{
struct mips_hi16 *n;
+ if (rela) {
+ *location = (*location & 0xffff0000) |
+ ((((long long) v + 0x8000LL) >> 16) & 0xffff);
+ return 0;
+ }
+
/*
* We cannot relocate this one now because we don't know the value of
* the carry we need to add. Save the information, and let LO16 do the
@@ -116,12 +95,18 @@ static void free_relocation_chain(struct mips_hi16 *l)
}
}
-static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_lo16(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela)
{
- unsigned long insnlo = *location;
+ unsigned long insnlo = base;
struct mips_hi16 *l;
Elf_Addr val, vallo;
+ if (rela) {
+ *location = (*location & 0xffff0000) | (v & 0xffff);
+ return 0;
+ }
+
/* Sign extend the addend we extract from the lo insn. */
vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
@@ -177,73 +162,232 @@ out_danger:
free_relocation_chain(l);
me->arch.r_mips_hi16_list = NULL;
- pr_err("module %s: dangerous R_MIPS_LO16 REL relocation\n", me->name);
+ pr_err("module %s: dangerous R_MIPS_LO16 relocation\n", me->name);
return -ENOEXEC;
}
-static int (*reloc_handlers_rel[]) (struct module *me, u32 *location,
- Elf_Addr v) = {
- [R_MIPS_NONE] = apply_r_mips_none,
- [R_MIPS_32] = apply_r_mips_32_rel,
- [R_MIPS_26] = apply_r_mips_26_rel,
- [R_MIPS_HI16] = apply_r_mips_hi16_rel,
- [R_MIPS_LO16] = apply_r_mips_lo16_rel
-};
+static int apply_r_mips_pc(struct module *me, u32 *location, u32 base,
+ Elf_Addr v, unsigned int bits)
+{
+ unsigned long mask = GENMASK(bits - 1, 0);
+ unsigned long se_bits;
+ long offset;
-int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
- unsigned int symindex, unsigned int relsec,
- struct module *me)
+ if (v % 4) {
+ pr_err("module %s: dangerous R_MIPS_PC%u relocation\n",
+ me->name, bits);
+ return -ENOEXEC;
+ }
+
+ /* retrieve & sign extend implicit addend if any */
+ offset = base & mask;
+ offset |= (offset & BIT(bits - 1)) ? ~mask : 0;
+
+ offset += ((long)v - (long)location) >> 2;
+
+ /* check the sign bit onwards are identical - ie. we didn't overflow */
+ se_bits = (offset & BIT(bits - 1)) ? ~0ul : 0;
+ if ((offset & ~mask) != (se_bits & ~mask)) {
+ pr_err("module %s: relocation overflow\n", me->name);
+ return -ENOEXEC;
+ }
+
+ *location = (*location & ~mask) | (offset & mask);
+
+ return 0;
+}
+
+static int apply_r_mips_pc16(struct module *me, u32 *location, u32 base,
+ Elf_Addr v)
+{
+ return apply_r_mips_pc(me, location, base, v, 16);
+}
+
+static int apply_r_mips_pc21(struct module *me, u32 *location, u32 base,
+ Elf_Addr v)
+{
+ return apply_r_mips_pc(me, location, base, v, 21);
+}
+
+static int apply_r_mips_pc26(struct module *me, u32 *location, u32 base,
+ Elf_Addr v)
+{
+ return apply_r_mips_pc(me, location, base, v, 26);
+}
+
+static int apply_r_mips_64(u32 *location, Elf_Addr v, bool rela)
+{
+ if (WARN_ON(!rela))
+ return -EINVAL;
+
+ *(Elf_Addr *)location = v;
+
+ return 0;
+}
+
+static int apply_r_mips_higher(u32 *location, Elf_Addr v, bool rela)
+{
+ if (WARN_ON(!rela))
+ return -EINVAL;
+
+ *location = (*location & 0xffff0000) |
+ ((((long long)v + 0x80008000LL) >> 32) & 0xffff);
+
+ return 0;
+}
+
+static int apply_r_mips_highest(u32 *location, Elf_Addr v, bool rela)
+{
+ if (WARN_ON(!rela))
+ return -EINVAL;
+
+ *location = (*location & 0xffff0000) |
+ ((((long long)v + 0x800080008000LL) >> 48) & 0xffff);
+
+ return 0;
+}
+
+/**
+ * reloc_handler() - Apply a particular relocation to a module
+ * @type: type of the relocation to apply
+ * @me: the module to apply the reloc to
+ * @location: the address at which the reloc is to be applied
+ * @base: the existing value at location for REL-style; 0 for RELA-style
+ * @v: the value of the reloc, with addend for RELA-style
+ * @rela: indication of is this a RELA (true) or REL (false) relocation
+ *
+ * Each implemented relocation function applies a particular type of
+ * relocation to the module @me. Relocs that may be found in either REL or RELA
+ * variants can be handled by making use of the @base & @v parameters which are
+ * set to values which abstract the difference away from the particular reloc
+ * implementations.
+ *
+ * Return: 0 upon success, else -ERRNO
+ */
+static int reloc_handler(u32 type, struct module *me, u32 *location, u32 base,
+ Elf_Addr v, bool rela)
{
- Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr;
+ switch (type) {
+ case R_MIPS_NONE:
+ break;
+ case R_MIPS_32:
+ apply_r_mips_32(location, base, v);
+ break;
+ case R_MIPS_26:
+ return apply_r_mips_26(me, location, base, v);
+ case R_MIPS_HI16:
+ return apply_r_mips_hi16(me, location, v, rela);
+ case R_MIPS_LO16:
+ return apply_r_mips_lo16(me, location, base, v, rela);
+ case R_MIPS_PC16:
+ return apply_r_mips_pc16(me, location, base, v);
+ case R_MIPS_PC21_S2:
+ return apply_r_mips_pc21(me, location, base, v);
+ case R_MIPS_PC26_S2:
+ return apply_r_mips_pc26(me, location, base, v);
+ case R_MIPS_64:
+ return apply_r_mips_64(location, v, rela);
+ case R_MIPS_HIGHER:
+ return apply_r_mips_higher(location, v, rela);
+ case R_MIPS_HIGHEST:
+ return apply_r_mips_highest(location, v, rela);
+ default:
+ pr_err("%s: Unknown relocation type %u\n", me->name, type);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *me, bool rela)
+{
+ union {
+ Elf_Mips_Rel *rel;
+ Elf_Mips_Rela *rela;
+ } r;
Elf_Sym *sym;
- u32 *location;
- unsigned int i;
+ u32 *location, base;
+ unsigned int i, type;
Elf_Addr v;
- int res;
+ int err = 0;
+ size_t reloc_sz;
pr_debug("Applying relocate section %u to %u\n", relsec,
sechdrs[relsec].sh_info);
+ r.rel = (void *)sechdrs[relsec].sh_addr;
+ reloc_sz = rela ? sizeof(*r.rela) : sizeof(*r.rel);
me->arch.r_mips_hi16_list = NULL;
- for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+ for (i = 0; i < sechdrs[relsec].sh_size / reloc_sz; i++) {
/* This is where to make the change */
location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
- + rel[i].r_offset;
+ + r.rel->r_offset;
/* This is the symbol it is referring to */
sym = (Elf_Sym *)sechdrs[symindex].sh_addr
- + ELF_MIPS_R_SYM(rel[i]);
- if (IS_ERR_VALUE(sym->st_value)) {
+ + ELF_MIPS_R_SYM(*r.rel);
+ if (sym->st_value >= -MAX_ERRNO) {
/* Ignore unresolved weak symbol */
if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
continue;
- printk(KERN_WARNING "%s: Unknown symbol %s\n",
- me->name, strtab + sym->st_name);
- return -ENOENT;
+ pr_warn("%s: Unknown symbol %s\n",
+ me->name, strtab + sym->st_name);
+ err = -ENOENT;
+ goto out;
}
- v = sym->st_value;
+ type = ELF_MIPS_R_TYPE(*r.rel);
+
+ if (rela) {
+ v = sym->st_value + r.rela->r_addend;
+ base = 0;
+ r.rela = &r.rela[1];
+ } else {
+ v = sym->st_value;
+ base = *location;
+ r.rel = &r.rel[1];
+ }
- res = reloc_handlers_rel[ELF_MIPS_R_TYPE(rel[i])](me, location, v);
- if (res)
- return res;
+ err = reloc_handler(type, me, location, base, v, rela);
+ if (err)
+ goto out;
}
+out:
/*
- * Normally the hi16 list should be deallocated at this point. A
+ * Normally the hi16 list should be deallocated at this point. A
* malformed binary however could contain a series of R_MIPS_HI16
- * relocations not followed by a R_MIPS_LO16 relocation. In that
- * case, free up the list and return an error.
+ * relocations not followed by a R_MIPS_LO16 relocation, or if we hit
+ * an error processing a reloc we might have gotten here before
+ * reaching the R_MIPS_LO16. In either case, free up the list and
+ * return an error.
*/
if (me->arch.r_mips_hi16_list) {
free_relocation_chain(me->arch.r_mips_hi16_list);
me->arch.r_mips_hi16_list = NULL;
-
- return -ENOEXEC;
+ err = err ?: -ENOEXEC;
}
- return 0;
+ return err;
+}
+
+int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *me)
+{
+ return __apply_relocate(sechdrs, strtab, symindex, relsec, me, false);
+}
+
+#ifdef CONFIG_MODULES_USE_ELF_RELA
+int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *me)
+{
+ return __apply_relocate(sechdrs, strtab, symindex, relsec, me, true);
}
+#endif /* CONFIG_MODULES_USE_ELF_RELA */
/* Given an address, look for it in the module exception tables. */
const struct exception_table_entry *search_module_dbetables(unsigned long addr)
@@ -254,7 +398,8 @@ const struct exception_table_entry *search_module_dbetables(unsigned long addr)
spin_lock_irqsave(&dbe_lock, flags);
list_for_each_entry(dbe, &dbe_list, dbe_list) {
- e = search_extable(dbe->dbe_start, dbe->dbe_end - 1, addr);
+ e = search_extable(dbe->dbe_start,
+ dbe->dbe_end - dbe->dbe_start, addr);
if (e)
break;
}
@@ -273,8 +418,8 @@ int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *s;
char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
- /* Make jump label nops. */
- jump_label_apply_nops(me);
+ if (IS_ENABLED(CONFIG_JUMP_LABEL))
+ jump_label_apply_nops(me);
INIT_LIST_HEAD(&me->arch.dbe_list);
for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
generated by cgit (git 2.34.1) at 2025-12-21 21:16:31 +0000