X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Usermode%2FLibraries%2Fld-acess.so_src%2Felf.c;h=e3109b4a624eb386ef1534dd0b669880c557aa67;hb=89fa44978be88e59366ee3e8939a1621f1ebc146;hp=bcf66ccd34f280109ed91efbc7d2c42df2fa1c63;hpb=e785cf0b01276ae9ebbb018dae2fe83d11e77701;p=tpg%2Facess2.git

diff --git a/Usermode/Libraries/ld-acess.so_src/elf.c b/Usermode/Libraries/ld-acess.so_src/elf.c
index bcf66ccd..e3109b4a 100644
--- a/Usermode/Libraries/ld-acess.so_src/elf.c
+++ b/Usermode/Libraries/ld-acess.so_src/elf.c
@@ -4,8 +4,10 @@
  *
  * elf.c
  * - ELF32/ELF64 relocation
+ *
+ * TODO: Have GetSymbol() return a symbol "strength" on success. Allows STB_WEAK to be overriden by STB_GLOBAL
  */
-#ifndef DEBUG	// This code is #include'd from the kernel, so DEBUG may already be defined
+#ifndef KERNEL_VERSION
 # define DEBUG	0
 #endif
 
@@ -29,7 +31,8 @@
 
 #define WARNING(f,...)	SysDebug("WARN: "f ,## __VA_ARGS__)	// Malformed file
 #define NOTICE(f,...)	SysDebug("NOTICE: "f ,## __VA_ARGS__)	// Missing relocation
-#define TRACE(f,...)	DEBUG_OUT("TRACE:%s:%i "f, __func__, __LINE__ ,## __VA_ARGS__)	// Debugging trace
+//#define TRACE(f,...)	DEBUG_OUT("TRACE:%s:%i "f, __func__, __LINE__ ,## __VA_ARGS__)	// Debugging trace
+#define TRACE(f,...)	DEBUG_OUT("TRACE:%s "f, __func__,## __VA_ARGS__)	// Debugging trace
 
 #ifndef DISABLE_ELF64
 # define SUPPORT_ELF64
@@ -151,12 +154,23 @@ int elf_doRelocate_386(tElfRelocInfo *Info, uint32_t r_info, uint32_t *ptr, Elf3
 	case R_386_COPY: {
 		void *old_symval = symval;
 		GetSymbol(Info->strtab + sym->st_name, &symval, &size, Info->Base);
-		if( symval == old_symval ) {
-			WARNING("Can't find required external symbol '%s'", Info->strtab + sym->st_name);
-			return 1;
+		if( symval == old_symval )
+		{
+			if( ELF32_ST_BIND(sym->st_info) != STB_WEAK )
+			{
+				WARNING("sym={val:%p,size:0x%x,info:0x%x,other:0x%x,shndx:%i}",
+					sym->st_value, sym->st_size, sym->st_info, sym->st_other, sym->st_shndx);
+				WARNING("Can't find required external symbol '%s' for R_386_COPY", Info->strtab + sym->st_name);
+				return 1;
+			}
+			// Don't bother doing the memcpy
+			TRACE("R_386_COPY (%p, %p, %i)", ptr, symval, size);
+		}
+		else
+		{
+			TRACE("R_386_COPY (%p, %p, %i)", ptr, symval, size);
+			memcpy(ptr, symval, size);
 		}
-		TRACE("R_386_COPY (%p, %p, %i)", ptr, symval, size);
-		memcpy(ptr, symval, size);
 		break; }
 
 	default:
@@ -223,7 +237,6 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename)
 	const Elf32_Ehdr	*hdr = Base;
 	char	*libPath;
 	intptr_t	iRealBase = -1;
-	intptr_t	iBaseDiff;
 	Elf32_Rel	*rel = NULL;
 	Elf32_Rela	*rela = NULL;
 	void	*plt = NULL;
@@ -264,10 +277,11 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename)
 	
 	// Page Align real base
 	iRealBase &= ~0xFFF;
-	TRACE("True Base = 0x%x, Compiled Base = 0x%x", Base, iRealBase);
 	
 	// Adjust "Real" Base
-	iBaseDiff = (intptr_t)Base - iRealBase;
+	const intptr_t	iBaseDiff = (intptr_t)Base - iRealBase;
+
+	TRACE("True Base = 0x%x, Compiled Base = 0x%x, Difference = 0x%x", Base, iRealBase, iBaseDiff);
 
 	// Check if a PT_DYNAMIC segement was found
 	if(!dynamicTab) {
@@ -342,15 +356,25 @@ void *Elf32Relocate(void *Base, char **envp, const char *Filename)
 		}
 		else
 		{
-			// TODO: What about weak locally-defined symbols?
-			if( ELF32_ST_BIND(sym->st_info) == STB_WEAK )
+			void *newval;
+			size_t	newsize;
+			if( ELF32_ST_BIND(sym->st_info) != STB_WEAK )
+			{
+				TRACE("Sym %i'%s' = %p (local)", i, name, sym->st_value + iBaseDiff);
+				sym->st_value += iBaseDiff;
+			}
+			// If GetSymbol doesn't return a strong/global symbol value
+			else if( GetSymbol(name, &newval, &newsize, Base) != 1 )
 			{
-				WARNING("TODO: Weak bound local symbols '%s'", name);
-				//assert(ELF32_ST_BIND(sym->st_info) != STB_WEAK);
-				//return NULL;
+				TRACE("Sym %i'%s' = %p (Local weak)", i, name, sym->st_value + iBaseDiff);
+				sym->st_value += iBaseDiff;
+			}
+			else
+			{
+				TRACE("Sym %i'%s' = %p+0x%x (Extern weak)", i, name, newval, newsize);
+				sym->st_value = (uintptr_t)newval;
+				sym->st_size = newsize;
 			}
-			TRACE("Sym %i'%s' %p += 0x%x", i, name, sym->st_value, iBaseDiff);
-			sym->st_value += iBaseDiff;
 		}
 	}
 
@@ -670,14 +694,18 @@ int Elf32GetSymbolInfo(void *Base, const char *Name, void **Addr, size_t *Size,
 
 int Elf32GetSymbol(void *Base, const char *Name, void **ret, size_t *Size)
 {
-	 int	section;
+	 int	section, binding;
 	TRACE("Elf32GetSymbol(%p,%s,...)", Base, Name);
-	if( Elf32GetSymbolInfo(Base, Name, ret, Size, &section, NULL, NULL) )
+	if( Elf32GetSymbolInfo(Base, Name, ret, Size, &section, &binding, NULL) )
 		return 0;
 	if( section == SHN_UNDEF ) {
-		TRACE("Elf32GetSymbol: Undefined", *ret, (Size?*Size:0), section);
+		TRACE("Elf32GetSymbol: Undefined %p", *ret, (Size?*Size:0), section);
 		return 0;
 	}
+	if( binding == STB_WEAK ) {
+		TRACE("Elf32GetSymbol: Weak, return %p+0x%x,section=%i", *ret, (Size?*Size:0), section);
+		return 2;
+	}
 	TRACE("Elf32GetSymbol: Found %p+0x%x,section=%i", *ret, (Size?*Size:0), section);
 	return 1;
 }