Index: head/include/dlfcn.h =================================================================== --- head/include/dlfcn.h +++ head/include/dlfcn.h @@ -47,6 +47,8 @@ #define RTLD_TRACE 0x200 /* Trace loaded objects and exit. */ #define RTLD_NODELETE 0x01000 /* Do not remove members. */ #define RTLD_NOLOAD 0x02000 /* Do not load if not already loaded. */ +#define RTLD_DEEPBIND 0x04000 /* Put symbols from the dso ahead of + the global list */ /* * Request arguments for dlinfo(). Index: head/lib/libc/gen/dlopen.3 =================================================================== --- head/lib/libc/gen/dlopen.3 +++ head/lib/libc/gen/dlopen.3 @@ -32,7 +32,7 @@ .\" @(#) dlopen.3 1.6 90/01/31 SMI .\" $FreeBSD$ .\" -.Dd January 2, 2019 +.Dd May 14, 2020 .Dt DLOPEN 3 .Os .Sh NAME @@ -162,6 +162,9 @@ is returned. Other mode flags may be specified, which will be applied for promotion for the found object. +.It Dv RTLD_DEEPBIND +Symbols from the loaded library are put before global symbols when +resolving symbolic references originated from the library. .El .Pp If Index: head/libexec/rtld-elf/rtld.h =================================================================== --- head/libexec/rtld-elf/rtld.h +++ head/libexec/rtld-elf/rtld.h @@ -309,6 +309,7 @@ #define RTLD_LO_EARLY 0x20 /* Do not call ctors, postpone it to the initialization during the image start. */ #define RTLD_LO_IGNSTLS 0x40 /* Do not allocate static TLS */ +#define RTLD_LO_DEEPBIND 0x80 /* Force symbolic for this object */ /* * Symbol cache entry used during relocation to avoid multiple lookups Index: head/libexec/rtld-elf/rtld.c =================================================================== --- head/libexec/rtld-elf/rtld.c +++ head/libexec/rtld-elf/rtld.c @@ -3366,6 +3366,8 @@ lo_flags |= RTLD_LO_NODELETE; if (mode & RTLD_NOLOAD) lo_flags |= RTLD_LO_NOLOAD; + if (mode & RTLD_DEEPBIND) + lo_flags |= RTLD_LO_DEEPBIND; if (ld_tracing != NULL) lo_flags |= RTLD_LO_TRACE | RTLD_LO_IGNSTLS; @@ -3417,6 +3419,8 @@ if (globallist_next(old_obj_tail) != NULL) { /* We loaded something new. */ assert(globallist_next(old_obj_tail) == obj); + if ((lo_flags & RTLD_LO_DEEPBIND) != 0) + obj->symbolic = true; result = 0; if ((lo_flags & (RTLD_LO_EARLY | RTLD_LO_IGNSTLS)) == 0 && obj->static_tls && !allocate_tls_offset(obj)) {