Author: kib Date: Tue Jun 2 16:20:58 2020 New Revision: 361725 URL: https://svnweb.freebsd.org/changeset/base/361725
Log: Do not allow to load ET_DYN object with DF_1_PIE flag set. Linkers are supposed to mark PIE binaries with DF_1_PIE, such binary cannot be correctly and usefully loaded neither by dlopen(3) nor as a dependency of other object. For instance, we cannot do anything useful with COPY relocations, among other things. Glibc already added similar restriction. Requested and reviewed by: emaste Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D25086 Modified: head/libexec/rtld-elf/rtld.c head/libexec/rtld-elf/rtld.h Modified: head/libexec/rtld-elf/rtld.c ============================================================================== --- head/libexec/rtld-elf/rtld.c Tue Jun 2 12:23:04 2020 (r361724) +++ head/libexec/rtld-elf/rtld.c Tue Jun 2 16:20:58 2020 (r361725) @@ -1370,6 +1370,8 @@ digest_dynamic1(Obj_Entry *obj, int early, const Elf_D obj->z_interpose = true; if (dynp->d_un.d_val & DF_1_NODEFLIB) obj->z_nodeflib = true; + if (dynp->d_un.d_val & DF_1_PIE) + obj->z_pie = true; break; default: @@ -2580,6 +2582,10 @@ do_load_object(int fd, const char *name, char *path, s obj->path = path; if (!digest_dynamic(obj, 0)) goto errp; + if (obj->z_pie) { + _rtld_error("Cannot load PIE binary %s as dso", obj->path); + goto errp; + } dbg("%s valid_hash_sysv %d valid_hash_gnu %d dynsymcount %d", obj->path, obj->valid_hash_sysv, obj->valid_hash_gnu, obj->dynsymcount); if (obj->z_noopen && (flags & (RTLD_LO_DLOPEN | RTLD_LO_TRACE)) == Modified: head/libexec/rtld-elf/rtld.h ============================================================================== --- head/libexec/rtld-elf/rtld.h Tue Jun 2 12:23:04 2020 (r361724) +++ head/libexec/rtld-elf/rtld.h Tue Jun 2 16:20:58 2020 (r361725) @@ -257,6 +257,7 @@ typedef struct Struct_Obj_Entry { bool z_interpose : 1; /* Interpose all objects but main */ bool z_nodeflib : 1; /* Don't search default library path */ bool z_global : 1; /* Make the object global */ + bool z_pie : 1; /* Object proclaimed itself PIE executable */ bool static_tls : 1; /* Needs static TLS allocation */ bool static_tls_copied : 1; /* Needs static TLS copying */ bool ref_nodel : 1; /* Refcount increased to prevent dlclose */ _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
