fix some symbol resolution issues in dynamic linker

1. search was wrongly beginning with lib itself rather than dso head
2. inconsistent resolution of function pointers for functions in plt

3 files changed, 6 insertions, 4 deletions

diff --git a/arch/i386/reloc.h b/arch/i386/reloc.h
index 3ca9d11d..490113a0 100644
--- a/arch/i386/reloc.h
+++ b/arch/i386/reloc.h
@@ -4,6 +4,7 @@
 #define ETC_LDSO_PATH "/etc/ld-musl-i386.path"
 
 #define IS_COPY(x) ((x)==R_386_COPY)
+#define IS_PLT(x) ((x)==R_386_JMP_SLOT)
 
 static inline void do_single_reloc(size_t *reloc_addr, int type, size_t sym_val, size_t sym_size, unsigned char *base_addr, size_t addend)
 {
diff --git a/arch/x86_64/reloc.h b/arch/x86_64/reloc.h
index 6642fdd4..b0bbfb3e 100644
--- a/arch/x86_64/reloc.h
+++ b/arch/x86_64/reloc.h
@@ -5,6 +5,7 @@
 #define ETC_LDSO_PATH "/etc/ld-musl-x86_64.path"
 
 #define IS_COPY(x) ((x)==R_X86_64_COPY)
+#define IS_PLT(x) ((x)==R_X86_64_JUMP_SLOT)
 
 static inline void do_single_reloc(size_t *reloc_addr, int type, size_t sym_val, size_t sym_size, unsigned char *base_addr, size_t addend)
 {
diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index 472e389d..9e9415ca 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -114,7 +114,7 @@ static void do_relocs(unsigned char *base, size_t *rel, size_t rel_size, size_t
 			sym = syms + sym_index;
 			name = strings + sym->st_name;
 			ctx = IS_COPY(type) ? dso->next : dso;
-			sym_val = (size_t)find_sym(ctx, name, 1);
+			sym_val = (size_t)find_sym(ctx, name, IS_PLT(type));
 			sym_size = sym->st_size;
 		}
 		do_single_reloc(reloc_addr, type, sym_val, sym_size, base, rel[2]);
@@ -335,11 +335,11 @@ static void reloc_all(struct dso *p)
 		if (p->relocated) continue;
 		decode_vec(p->dynv, dyn, DYN_CNT);
 		do_relocs(p->base, (void *)(p->base+dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
-			2+(dyn[DT_PLTREL]==DT_RELA), p->syms, p->strings, p);
+			2+(dyn[DT_PLTREL]==DT_RELA), p->syms, p->strings, head);
 		do_relocs(p->base, (void *)(p->base+dyn[DT_REL]), dyn[DT_RELSZ],
-			2, p->syms, p->strings, p);
+			2, p->syms, p->strings, head);
 		do_relocs(p->base, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ],
-			3, p->syms, p->strings, p);
+			3, p->syms, p->strings, head);
 		p->relocated = 1;
 	}
 }