Implement support for ELF filters in rtld. Both normal and auxillary

filters are implemented.

Filtees are loaded on demand, unless LD_LOADFLTR environment variable
is set or -z loadfltr was specified during the linking. This forces
rtld to upgrade read-locked rtld_bind_lock to write lock when it
encounters an object with filter during symbol lookup.

Consolidate common arguments of the symbol lookup functions in the
SymLook structure.  Track the state of the rtld locks in the
RtldLockState structure. Pass local RtldLockState through the rtld
symbol lookup calls to allow lock upgrades.

Reviewed by:	kan
Tested by:	Mykola Dzham <i levsha me>, nwhitehorn (powerpc)

1 files changed, 14 insertions, 13 deletions

diff --git a/libexec/rtld-elf/ia64/reloc.c b/libexec/rtld-elf/ia64/reloc.c
index 728fe30..6ee0947 100644
--- a/libexec/rtld-elf/ia64/reloc.c
+++ b/libexec/rtld-elf/ia64/reloc.c
@@ -151,7 +151,7 @@ free_fptrs(Obj_Entry *obj, bool mapped)
 /* Relocate a non-PLT object with addend. */
 static int
 reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
-		  SymCache *cache)
+    SymCache *cache, RtldLockState *lockstate)
 {
 	struct fptr **fptrs;
 	Elf_Addr *where = (Elf_Addr *) (obj->relocbase + rela->r_offset);
@@ -172,7 +172,7 @@ reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
 		Elf_Addr target;
 
 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
-				  false, cache);
+		    false, cache, lockstate);
 		if (def == NULL)
 			return -1;
 
@@ -195,7 +195,7 @@ reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
 		int sym_index;
 
 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
-				  true, cache);
+		    true, cache, lockstate);
 		if (def == NULL) {
 			/*
 			 * XXX r_debug_state is problematic and find_symdef()
@@ -254,7 +254,7 @@ reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
 		Elf_Addr target, gp;
 
 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
-				  false, cache);
+		    false, cache, lockstate);
 		if (def == NULL)
 			return -1;
 
@@ -277,7 +277,7 @@ reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
 		const Obj_Entry *defobj;
 
 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
-				  false, cache);
+		    false, cache, lockstate);
 		if (def == NULL)
 			return -1;
 
@@ -290,7 +290,7 @@ reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
 		const Obj_Entry *defobj;
 
 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
-				  false, cache);
+		    false, cache, lockstate);
 		if (def == NULL)
 			return -1;
 
@@ -303,7 +303,7 @@ reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
 		const Obj_Entry *defobj;
 
 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
-				  false, cache);
+		    false, cache, lockstate);
 		if (def == NULL)
 			return -1;
 
@@ -342,7 +342,7 @@ reloc_non_plt_obj(Obj_Entry *obj_rtld, Obj_Entry *obj, const Elf_Rela *rela,
 
 /* Process the non-PLT relocations. */
 int
-reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld)
+reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, RtldLockState *lockstate)
 {
 	const Elf_Rel *rellim;
 	const Elf_Rel *rel;
@@ -368,14 +368,15 @@ reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld)
 		locrela.r_info = rel->r_info;
 		locrela.r_offset = rel->r_offset;
 		locrela.r_addend = 0;
-		if (reloc_non_plt_obj(obj_rtld, obj, &locrela, cache))
+		if (reloc_non_plt_obj(obj_rtld, obj, &locrela, cache,
+		    lockstate))
 			goto done;
 	}
 
 	/* Perform relocations with addend if there are any: */
 	relalim = (const Elf_Rela *) ((caddr_t) obj->rela + obj->relasize);
 	for (rela = obj->rela;  obj->rela != NULL && rela < relalim;  rela++) {
-		if (reloc_non_plt_obj(obj_rtld, obj, rela, cache))
+		if (reloc_non_plt_obj(obj_rtld, obj, rela, cache, lockstate))
 			goto done;
 	}
 
@@ -436,7 +437,7 @@ reloc_plt(Obj_Entry *obj)
 
 /* Relocate the jump slots in an object. */
 int
-reloc_jmpslots(Obj_Entry *obj)
+reloc_jmpslots(Obj_Entry *obj, RtldLockState *lockstate)
 {
 	if (obj->jmpslots_done)
 		return 0;
@@ -455,7 +456,7 @@ reloc_jmpslots(Obj_Entry *obj)
 			assert(ELF_R_TYPE(rel->r_info) == R_IA_64_IPLTLSB);
 			where = (Elf_Addr *)(obj->relocbase + rel->r_offset);
 			def = find_symdef(ELF_R_SYM(rel->r_info), obj,
-					  &defobj, true, NULL);
+			    &defobj, true, NULL, lockstate);
 			if (def == NULL)
 				return -1;
 			reloc_jmpslot(where,
@@ -476,7 +477,7 @@ reloc_jmpslots(Obj_Entry *obj)
 
 			where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
 			def = find_symdef(ELF_R_SYM(rela->r_info), obj,
-					  &defobj, true, NULL);
+			    &defobj, true, NULL, lockstate);
 			if (def == NULL)
 				return -1;
 			reloc_jmpslot(where,