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Diffstat (limited to 'arch/mips/kernel/module.c')
-rw-r--r--arch/mips/kernel/module.c221
1 files changed, 165 insertions, 56 deletions
diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c
index 50c020c47e54..491605137b03 100644
--- a/arch/mips/kernel/module.c
+++ b/arch/mips/kernel/module.c
@@ -53,22 +53,25 @@ void *module_alloc(unsigned long size)
}
#endif
-int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_none(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela)
{
return 0;
}
-static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_32(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela)
{
- *location += v;
+ *location = base + 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, bool rela)
{
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;
}
@@ -80,15 +83,22 @@ static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v)
}
*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,
+ u32 base, 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
@@ -117,12 +127,18 @@ 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;
@@ -178,26 +194,26 @@ 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 apply_r_mips_pc_rel(struct module *me, u32 *location, Elf_Addr v,
- unsigned bits)
+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;
if (v % 4) {
- pr_err("module %s: dangerous R_MIPS_PC%u REL relocation\n",
+ pr_err("module %s: dangerous R_MIPS_PC%u relocation\n",
me->name, bits);
return -ENOEXEC;
}
- /* retrieve & sign extend implicit addend */
- offset = *location & mask;
+ /* retrieve & sign extend implicit addend if any */
+ offset = base & mask;
offset |= (offset & BIT(bits - 1)) ? ~mask : 0;
offset += ((long)v - (long)location) >> 2;
@@ -214,99 +230,192 @@ static int apply_r_mips_pc_rel(struct module *me, u32 *location, Elf_Addr v,
return 0;
}
-static int apply_r_mips_pc16_rel(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_pc16(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela)
+{
+ 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, bool rela)
+{
+ 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, bool rela)
+{
+ return apply_r_mips_pc(me, location, base, v, 26);
+}
+
+static int apply_r_mips_64(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela)
{
- return apply_r_mips_pc_rel(me, location, v, 16);
+ if (WARN_ON(!rela))
+ return -EINVAL;
+
+ *(Elf_Addr *)location = v;
+
+ return 0;
}
-static int apply_r_mips_pc21_rel(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_higher(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela)
{
- return apply_r_mips_pc_rel(me, location, v, 21);
+ if (WARN_ON(!rela))
+ return -EINVAL;
+
+ *location = (*location & 0xffff0000) |
+ ((((long long)v + 0x80008000LL) >> 32) & 0xffff);
+
+ return 0;
}
-static int apply_r_mips_pc26_rel(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_mips_highest(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela)
{
- return apply_r_mips_pc_rel(me, location, v, 26);
+ if (WARN_ON(!rela))
+ return -EINVAL;
+
+ *location = (*location & 0xffff0000) |
+ ((((long long)v + 0x800080008000LL) >> 48) & 0xffff);
+
+ return 0;
}
-static int (*reloc_handlers_rel[]) (struct module *me, u32 *location,
- Elf_Addr v) = {
+/**
+ * reloc_handler() - Apply a particular relocation to a module
+ * @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
+ *
+ * Each implemented reloc_handler 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
+ */
+typedef int (*reloc_handler)(struct module *me, u32 *location,
+ u32 base, Elf_Addr v, bool rela);
+
+/* The handlers for known reloc types */
+static reloc_handler reloc_handlers[] = {
[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,
- [R_MIPS_PC16] = apply_r_mips_pc16_rel,
- [R_MIPS_PC21_S2] = apply_r_mips_pc21_rel,
- [R_MIPS_PC26_S2] = apply_r_mips_pc26_rel,
+ [R_MIPS_32] = apply_r_mips_32,
+ [R_MIPS_26] = apply_r_mips_26,
+ [R_MIPS_HI16] = apply_r_mips_hi16,
+ [R_MIPS_LO16] = apply_r_mips_lo16,
+ [R_MIPS_PC16] = apply_r_mips_pc16,
+ [R_MIPS_64] = apply_r_mips_64,
+ [R_MIPS_HIGHER] = apply_r_mips_higher,
+ [R_MIPS_HIGHEST] = apply_r_mips_highest,
+ [R_MIPS_PC21_S2] = apply_r_mips_pc21,
+ [R_MIPS_PC26_S2] = apply_r_mips_pc26,
};
-int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
- unsigned int symindex, unsigned int relsec,
- struct module *me)
+static int __apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *me, bool rela)
{
- Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr;
- int (*handler)(struct module *me, u32 *location, Elf_Addr v);
+ union {
+ Elf_Mips_Rel *rel;
+ Elf_Mips_Rela *rela;
+ } r;
+ reloc_handler handler;
Elf_Sym *sym;
- u32 *location;
+ 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]);
+ + 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;
pr_warn("%s: Unknown symbol %s\n",
me->name, strtab + sym->st_name);
- return -ENOENT;
+ err = -ENOENT;
+ goto out;
}
- type = ELF_MIPS_R_TYPE(rel[i]);
-
- if (type < ARRAY_SIZE(reloc_handlers_rel))
- handler = reloc_handlers_rel[type];
+ type = ELF_MIPS_R_TYPE(*r.rel);
+ if (type < ARRAY_SIZE(reloc_handlers))
+ handler = reloc_handlers[type];
else
handler = NULL;
if (!handler) {
pr_err("%s: Unknown relocation type %u\n",
me->name, type);
- return -EINVAL;
+ err = -EINVAL;
+ goto out;
}
- v = sym->st_value;
- res = handler(me, location, v);
- if (res)
- return res;
+ 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];
+ }
+
+ err = handler(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)
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-01 12:36:49 +0300