diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/dl-load.c | 3 | ||||
| -rw-r--r-- | elf/dl-support.c | 1 | ||||
| -rw-r--r-- | elf/rtld.c | 18 |
3 files changed, 21 insertions, 1 deletions
diff --git a/elf/dl-load.c b/elf/dl-load.c index ecf2ee87eb..c7e3716cb6 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -1096,7 +1096,8 @@ cannot allocate TLS data structures for initial thread"); prefer to map such objects at; but this is only a preference, the OS can do whatever it likes. */ ElfW(Addr) mappref; - mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart) + mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, + c->mapstart & GL(dl_use_load_bias)) - MAP_BASE_ADDR (l)); /* Remember which part of the address space this object uses. */ diff --git a/elf/dl-support.c b/elf/dl-support.c index 448f4c6848..f13fd058a3 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -41,6 +41,7 @@ size_t _dl_platformlen; int _dl_debug_mask; int _dl_lazy; +ElfW(Addr) _dl_use_load_bias = -2; int _dl_dynamic_weak; /* If nonzero print warnings about problematic situations. */ diff --git a/elf/rtld.c b/elf/rtld.c index e92149a667..82f7ed3fc2 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -95,6 +95,7 @@ struct rtld_global _rtld_global = ._dl_sysinfo = DL_SYSINFO_DEFAULT, #endif ._dl_lazy = 1, + ._dl_use_load_bias = -2, ._dl_fpu_control = _FPU_DEFAULT, ._dl_correct_cache_id = _DL_CACHE_DEFAULT_ID, ._dl_hwcap_mask = HWCAP_IMPORTANT, @@ -996,6 +997,12 @@ of this helper program; chances are you did not intend to run this program.\n\ GL(dl_rtld_map).l_prev = GL(dl_loaded); ++GL(dl_nloaded); + /* If LD_USE_LOAD_BIAS env variable has not been seen, default + to not using bias for non-prelinked PIEs and libraries + and using it for executables or prelinked PIEs or libraries. */ + if (GL(dl_use_load_bias) == (ElfW(Addr)) -2) + GL(dl_use_load_bias) = (GL(dl_loaded)->l_addr == 0) ? -1 : 0; + /* Set up the program header information for the dynamic linker itself. It is needed in the dl_iterate_phdr() callbacks. */ ElfW(Ehdr) *rtld_ehdr = (ElfW(Ehdr) *) GL(dl_rtld_map).l_map_start; @@ -1992,6 +1999,17 @@ process_envvars (enum mode *modep) GL(dl_dynamic_weak) = 1; break; + case 13: + /* We might have some extra environment variable with length 13 + to handle. */ +#ifdef EXTRA_LD_ENVVARS_13 + EXTRA_LD_ENVVARS_13 +#endif + if (!INTUSE(__libc_enable_secure) + && memcmp (envline, "USE_LOAD_BIAS", 13) == 0) + GL(dl_use_load_bias) = envline[14] == '1' ? -1 : 0; + break; + case 14: /* Where to place the profiling data file. */ if (!INTUSE(__libc_enable_secure) |