Update Linux to v5.10.157
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.157.tar.xz
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I7b30d9e98d8c465d6b44de8e7433b4a40b3289ba
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index d8421e1..a2ea393 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -262,32 +262,6 @@
return find_reloc_by_dest_range(elf, sec, offset, 1);
}
-void insn_to_reloc_sym_addend(struct section *sec, unsigned long offset,
- struct reloc *reloc)
-{
- if (sec->sym) {
- reloc->sym = sec->sym;
- reloc->addend = offset;
- return;
- }
-
- /*
- * The Clang assembler strips section symbols, so we have to reference
- * the function symbol instead:
- */
- reloc->sym = find_symbol_containing(sec, offset);
- if (!reloc->sym) {
- /*
- * Hack alert. This happens when we need to reference the NOP
- * pad insn immediately after the function.
- */
- reloc->sym = find_symbol_containing(sec, offset - 1);
- }
-
- if (reloc->sym)
- reloc->addend = offset - reloc->sym->offset;
-}
-
static int read_sections(struct elf *elf)
{
Elf_Scn *s = NULL;
@@ -367,12 +341,41 @@
return 0;
}
+static void elf_add_symbol(struct elf *elf, struct symbol *sym)
+{
+ struct list_head *entry;
+ struct rb_node *pnode;
+
+ sym->alias = sym;
+
+ sym->type = GELF_ST_TYPE(sym->sym.st_info);
+ sym->bind = GELF_ST_BIND(sym->sym.st_info);
+
+ sym->offset = sym->sym.st_value;
+ sym->len = sym->sym.st_size;
+
+ rb_add(&sym->sec->symbol_tree, &sym->node, symbol_to_offset);
+ pnode = rb_prev(&sym->node);
+ if (pnode)
+ entry = &rb_entry(pnode, struct symbol, node)->list;
+ else
+ entry = &sym->sec->symbol_list;
+ list_add(&sym->list, entry);
+ elf_hash_add(elf->symbol_hash, &sym->hash, sym->idx);
+ elf_hash_add(elf->symbol_name_hash, &sym->name_hash, str_hash(sym->name));
+
+ /*
+ * Don't store empty STT_NOTYPE symbols in the rbtree. They
+ * can exist within a function, confusing the sorting.
+ */
+ if (!sym->len)
+ rb_erase(&sym->node, &sym->sec->symbol_tree);
+}
+
static int read_symbols(struct elf *elf)
{
struct section *symtab, *symtab_shndx, *sec;
struct symbol *sym, *pfunc;
- struct list_head *entry;
- struct rb_node *pnode;
int symbols_nr, i;
char *coldstr;
Elf_Data *shndx_data = NULL;
@@ -400,7 +403,6 @@
return -1;
}
memset(sym, 0, sizeof(*sym));
- sym->alias = sym;
sym->idx = i;
@@ -417,9 +419,6 @@
goto err;
}
- sym->type = GELF_ST_TYPE(sym->sym.st_info);
- sym->bind = GELF_ST_BIND(sym->sym.st_info);
-
if ((sym->sym.st_shndx > SHN_UNDEF &&
sym->sym.st_shndx < SHN_LORESERVE) ||
(shndx_data && sym->sym.st_shndx == SHN_XINDEX)) {
@@ -432,32 +431,14 @@
sym->name);
goto err;
}
- if (sym->type == STT_SECTION) {
+ if (GELF_ST_TYPE(sym->sym.st_info) == STT_SECTION) {
sym->name = sym->sec->name;
sym->sec->sym = sym;
}
} else
sym->sec = find_section_by_index(elf, 0);
- sym->offset = sym->sym.st_value;
- sym->len = sym->sym.st_size;
-
- rb_add(&sym->sec->symbol_tree, &sym->node, symbol_to_offset);
- pnode = rb_prev(&sym->node);
- if (pnode)
- entry = &rb_entry(pnode, struct symbol, node)->list;
- else
- entry = &sym->sec->symbol_list;
- list_add(&sym->list, entry);
- elf_hash_add(elf->symbol_hash, &sym->hash, sym->idx);
- elf_hash_add(elf->symbol_name_hash, &sym->name_hash, str_hash(sym->name));
-
- /*
- * Don't store empty STT_NOTYPE symbols in the rbtree. They
- * can exist within a function, confusing the sorting.
- */
- if (!sym->len)
- rb_erase(&sym->node, &sym->sec->symbol_tree);
+ elf_add_symbol(elf, sym);
}
if (stats)
@@ -524,12 +505,280 @@
return -1;
}
-void elf_add_reloc(struct elf *elf, struct reloc *reloc)
-{
- struct section *sec = reloc->sec;
+static struct section *elf_create_reloc_section(struct elf *elf,
+ struct section *base,
+ int reltype);
- list_add_tail(&reloc->list, &sec->reloc_list);
+int elf_add_reloc(struct elf *elf, struct section *sec, unsigned long offset,
+ unsigned int type, struct symbol *sym, s64 addend)
+{
+ struct reloc *reloc;
+
+ if (!sec->reloc && !elf_create_reloc_section(elf, sec, SHT_RELA))
+ return -1;
+
+ reloc = malloc(sizeof(*reloc));
+ if (!reloc) {
+ perror("malloc");
+ return -1;
+ }
+ memset(reloc, 0, sizeof(*reloc));
+
+ reloc->sec = sec->reloc;
+ reloc->offset = offset;
+ reloc->type = type;
+ reloc->sym = sym;
+ reloc->addend = addend;
+
+ list_add_tail(&reloc->list, &sec->reloc->reloc_list);
elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc));
+
+ sec->reloc->changed = true;
+
+ return 0;
+}
+
+/*
+ * Ensure that any reloc section containing references to @sym is marked
+ * changed such that it will get re-generated in elf_rebuild_reloc_sections()
+ * with the new symbol index.
+ */
+static void elf_dirty_reloc_sym(struct elf *elf, struct symbol *sym)
+{
+ struct section *sec;
+
+ list_for_each_entry(sec, &elf->sections, list) {
+ struct reloc *reloc;
+
+ if (sec->changed)
+ continue;
+
+ list_for_each_entry(reloc, &sec->reloc_list, list) {
+ if (reloc->sym == sym) {
+ sec->changed = true;
+ break;
+ }
+ }
+ }
+}
+
+/*
+ * The libelf API is terrible; gelf_update_sym*() takes a data block relative
+ * index value, *NOT* the symbol index. As such, iterate the data blocks and
+ * adjust index until it fits.
+ *
+ * If no data block is found, allow adding a new data block provided the index
+ * is only one past the end.
+ */
+static int elf_update_symbol(struct elf *elf, struct section *symtab,
+ struct section *symtab_shndx, struct symbol *sym)
+{
+ Elf32_Word shndx = sym->sec ? sym->sec->idx : SHN_UNDEF;
+ Elf_Data *symtab_data = NULL, *shndx_data = NULL;
+ Elf64_Xword entsize = symtab->sh.sh_entsize;
+ int max_idx, idx = sym->idx;
+ Elf_Scn *s, *t = NULL;
+ bool is_special_shndx = sym->sym.st_shndx >= SHN_LORESERVE &&
+ sym->sym.st_shndx != SHN_XINDEX;
+
+ if (is_special_shndx)
+ shndx = sym->sym.st_shndx;
+
+ s = elf_getscn(elf->elf, symtab->idx);
+ if (!s) {
+ WARN_ELF("elf_getscn");
+ return -1;
+ }
+
+ if (symtab_shndx) {
+ t = elf_getscn(elf->elf, symtab_shndx->idx);
+ if (!t) {
+ WARN_ELF("elf_getscn");
+ return -1;
+ }
+ }
+
+ for (;;) {
+ /* get next data descriptor for the relevant sections */
+ symtab_data = elf_getdata(s, symtab_data);
+ if (t)
+ shndx_data = elf_getdata(t, shndx_data);
+
+ /* end-of-list */
+ if (!symtab_data) {
+ void *buf;
+
+ if (idx) {
+ /* we don't do holes in symbol tables */
+ WARN("index out of range");
+ return -1;
+ }
+
+ /* if @idx == 0, it's the next contiguous entry, create it */
+ symtab_data = elf_newdata(s);
+ if (t)
+ shndx_data = elf_newdata(t);
+
+ buf = calloc(1, entsize);
+ if (!buf) {
+ WARN("malloc");
+ return -1;
+ }
+
+ symtab_data->d_buf = buf;
+ symtab_data->d_size = entsize;
+ symtab_data->d_align = 1;
+ symtab_data->d_type = ELF_T_SYM;
+
+ symtab->sh.sh_size += entsize;
+ symtab->changed = true;
+
+ if (t) {
+ shndx_data->d_buf = &sym->sec->idx;
+ shndx_data->d_size = sizeof(Elf32_Word);
+ shndx_data->d_align = sizeof(Elf32_Word);
+ shndx_data->d_type = ELF_T_WORD;
+
+ symtab_shndx->sh.sh_size += sizeof(Elf32_Word);
+ symtab_shndx->changed = true;
+ }
+
+ break;
+ }
+
+ /* empty blocks should not happen */
+ if (!symtab_data->d_size) {
+ WARN("zero size data");
+ return -1;
+ }
+
+ /* is this the right block? */
+ max_idx = symtab_data->d_size / entsize;
+ if (idx < max_idx)
+ break;
+
+ /* adjust index and try again */
+ idx -= max_idx;
+ }
+
+ /* something went side-ways */
+ if (idx < 0) {
+ WARN("negative index");
+ return -1;
+ }
+
+ /* setup extended section index magic and write the symbol */
+ if ((shndx >= SHN_UNDEF && shndx < SHN_LORESERVE) || is_special_shndx) {
+ sym->sym.st_shndx = shndx;
+ if (!shndx_data)
+ shndx = 0;
+ } else {
+ sym->sym.st_shndx = SHN_XINDEX;
+ if (!shndx_data) {
+ WARN("no .symtab_shndx");
+ return -1;
+ }
+ }
+
+ if (!gelf_update_symshndx(symtab_data, shndx_data, idx, &sym->sym, shndx)) {
+ WARN_ELF("gelf_update_symshndx");
+ return -1;
+ }
+
+ return 0;
+}
+
+static struct symbol *
+elf_create_section_symbol(struct elf *elf, struct section *sec)
+{
+ struct section *symtab, *symtab_shndx;
+ Elf32_Word first_non_local, new_idx;
+ struct symbol *sym, *old;
+
+ symtab = find_section_by_name(elf, ".symtab");
+ if (symtab) {
+ symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
+ } else {
+ WARN("no .symtab");
+ return NULL;
+ }
+
+ sym = calloc(1, sizeof(*sym));
+ if (!sym) {
+ perror("malloc");
+ return NULL;
+ }
+
+ sym->name = sec->name;
+ sym->sec = sec;
+
+ // st_name 0
+ sym->sym.st_info = GELF_ST_INFO(STB_LOCAL, STT_SECTION);
+ // st_other 0
+ // st_value 0
+ // st_size 0
+
+ /*
+ * Move the first global symbol, as per sh_info, into a new, higher
+ * symbol index. This fees up a spot for a new local symbol.
+ */
+ first_non_local = symtab->sh.sh_info;
+ new_idx = symtab->sh.sh_size / symtab->sh.sh_entsize;
+ old = find_symbol_by_index(elf, first_non_local);
+ if (old) {
+ old->idx = new_idx;
+
+ hlist_del(&old->hash);
+ elf_hash_add(elf->symbol_hash, &old->hash, old->idx);
+
+ elf_dirty_reloc_sym(elf, old);
+
+ if (elf_update_symbol(elf, symtab, symtab_shndx, old)) {
+ WARN("elf_update_symbol move");
+ return NULL;
+ }
+
+ new_idx = first_non_local;
+ }
+
+ sym->idx = new_idx;
+ if (elf_update_symbol(elf, symtab, symtab_shndx, sym)) {
+ WARN("elf_update_symbol");
+ return NULL;
+ }
+
+ /*
+ * Either way, we added a LOCAL symbol.
+ */
+ symtab->sh.sh_info += 1;
+
+ elf_add_symbol(elf, sym);
+
+ return sym;
+}
+
+int elf_add_reloc_to_insn(struct elf *elf, struct section *sec,
+ unsigned long offset, unsigned int type,
+ struct section *insn_sec, unsigned long insn_off)
+{
+ struct symbol *sym = insn_sec->sym;
+ int addend = insn_off;
+
+ if (!sym) {
+ /*
+ * Due to how weak functions work, we must use section based
+ * relocations. Symbol based relocations would result in the
+ * weak and non-weak function annotations being overlaid on the
+ * non-weak function after linking.
+ */
+ sym = elf_create_section_symbol(elf, insn_sec);
+ if (!sym)
+ return -1;
+
+ insn_sec->sym = sym;
+ }
+
+ return elf_add_reloc(elf, sec, offset, type, sym, addend);
}
static int read_rel_reloc(struct section *sec, int i, struct reloc *reloc, unsigned int *symndx)
@@ -609,7 +858,9 @@
return -1;
}
- elf_add_reloc(elf, reloc);
+ list_add_tail(&reloc->list, &sec->reloc_list);
+ elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc));
+
nr_reloc++;
}
max_reloc = max(max_reloc, nr_reloc);
@@ -687,13 +938,49 @@
return NULL;
}
+static int elf_add_string(struct elf *elf, struct section *strtab, char *str)
+{
+ Elf_Data *data;
+ Elf_Scn *s;
+ int len;
+
+ if (!strtab)
+ strtab = find_section_by_name(elf, ".strtab");
+ if (!strtab) {
+ WARN("can't find .strtab section");
+ return -1;
+ }
+
+ s = elf_getscn(elf->elf, strtab->idx);
+ if (!s) {
+ WARN_ELF("elf_getscn");
+ return -1;
+ }
+
+ data = elf_newdata(s);
+ if (!data) {
+ WARN_ELF("elf_newdata");
+ return -1;
+ }
+
+ data->d_buf = str;
+ data->d_size = strlen(str) + 1;
+ data->d_align = 1;
+ data->d_type = ELF_T_SYM;
+
+ len = strtab->len;
+ strtab->len += data->d_size;
+ strtab->changed = true;
+
+ return len;
+}
+
struct section *elf_create_section(struct elf *elf, const char *name,
unsigned int sh_flags, size_t entsize, int nr)
{
struct section *sec, *shstrtab;
size_t size = entsize * nr;
Elf_Scn *s;
- Elf_Data *data;
sec = malloc(sizeof(*sec));
if (!sec) {
@@ -750,7 +1037,6 @@
sec->sh.sh_addralign = 1;
sec->sh.sh_flags = SHF_ALLOC | sh_flags;
-
/* Add section name to .shstrtab (or .strtab for Clang) */
shstrtab = find_section_by_name(elf, ".shstrtab");
if (!shstrtab)
@@ -759,27 +1045,9 @@
WARN("can't find .shstrtab or .strtab section");
return NULL;
}
-
- s = elf_getscn(elf->elf, shstrtab->idx);
- if (!s) {
- WARN_ELF("elf_getscn");
+ sec->sh.sh_name = elf_add_string(elf, shstrtab, sec->name);
+ if (sec->sh.sh_name == -1)
return NULL;
- }
-
- data = elf_newdata(s);
- if (!data) {
- WARN_ELF("elf_newdata");
- return NULL;
- }
-
- data->d_buf = sec->name;
- data->d_size = strlen(name) + 1;
- data->d_align = 1;
-
- sec->sh.sh_name = shstrtab->len;
-
- shstrtab->len += strlen(name) + 1;
- shstrtab->changed = true;
list_add_tail(&sec->list, &elf->sections);
elf_hash_add(elf->section_hash, &sec->hash, sec->idx);
@@ -850,7 +1118,7 @@
return sec;
}
-struct section *elf_create_reloc_section(struct elf *elf,
+static struct section *elf_create_reloc_section(struct elf *elf,
struct section *base,
int reltype)
{
@@ -920,14 +1188,11 @@
return 0;
}
-int elf_rebuild_reloc_section(struct elf *elf, struct section *sec)
+static int elf_rebuild_reloc_section(struct elf *elf, struct section *sec)
{
struct reloc *reloc;
int nr;
- sec->changed = true;
- elf->changed = true;
-
nr = 0;
list_for_each_entry(reloc, &sec->reloc_list, list)
nr++;
@@ -991,9 +1256,15 @@
struct section *sec;
Elf_Scn *s;
- /* Update section headers for changed sections: */
+ /* Update changed relocation sections and section headers: */
list_for_each_entry(sec, &elf->sections, list) {
if (sec->changed) {
+ if (sec->base &&
+ elf_rebuild_reloc_section(elf, sec)) {
+ WARN("elf_rebuild_reloc_section");
+ return -1;
+ }
+
s = elf_getscn(elf->elf, sec->idx);
if (!s) {
WARN_ELF("elf_getscn");
@@ -1005,6 +1276,7 @@
}
sec->changed = false;
+ elf->changed = true;
}
}