| commit f6a54a304223666ea4af73260c99c830d7726eca |
| Author: Adhemerval Zanella <adhemerval.zanella@linaro.org> |
| Date: Fri Oct 15 14:35:31 2021 -0300 |
| |
| elf: Fix elf_get_dynamic_info() for bootstrap |
| |
| THe d6d89608ac8c broke powerpc for --enable-bind-now because it turned |
| out that different than patch assumption rtld elf_get_dynamic_info() |
| does require to handle RTLD_BOOTSTRAP to avoid DT_FLAGS and |
| DT_RUNPATH (more specially the GLRO usage which is not reallocate |
| yet). |
| |
| This patch fixes by passing two arguments to elf_get_dynamic_info() |
| to inform that by rtld (bootstrap) or static pie initialization |
| (static_pie_bootstrap). I think using explicit argument is way more |
| clear and burried C preprocessor, and compiler should remove the |
| dead code. |
| |
| I checked on x86_64 and i686 with default options, --enable-bind-now, |
| and --enable-bind-now and --enable--static-pie. I also check on |
| aarch64, armhf, powerpc64, and powerpc with default and |
| --enable-bind-now. |
| |
| (cherry picked from commit 5118dcac68c4eadfd6304bb33adde63d062dc07f) |
| |
| Resolved conflicts: |
| elf/rtld.c - Manual merge. |
| |
| diff --git a/elf/dl-load.c b/elf/dl-load.c |
| index fb3da5aa565908a6..a920b12a906a9dec 100644 |
| |
| |
| @@ -1296,7 +1296,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, |
| if (l->l_ld != 0) |
| l->l_ld = (ElfW(Dyn) *) ((ElfW(Addr)) l->l_ld + l->l_addr); |
| |
| - elf_get_dynamic_info (l); |
| + elf_get_dynamic_info (l, false, false); |
| |
| /* Make sure we are not dlopen'ing an object that has the |
| DF_1_NOOPEN flag set, or a PIE object. */ |
| diff --git a/elf/dl-reloc-static-pie.c b/elf/dl-reloc-static-pie.c |
| index ababafcf98f9945d..757205affe65d9e1 100644 |
| |
| |
| @@ -25,7 +25,6 @@ |
| |
| #include <dl-machine.h> |
| |
| -#define STATIC_PIE_BOOTSTRAP |
| #define RESOLVE_MAP(map, scope, sym, version, flags) map |
| #include "dynamic-link.h" |
| #include "get-dynamic-info.h" |
| @@ -52,7 +51,7 @@ _dl_relocate_static_pie (void) |
| break; |
| } |
| |
| - elf_get_dynamic_info (main_map); |
| + elf_get_dynamic_info (main_map, false, true); |
| |
| # ifdef ELF_MACHINE_BEFORE_RTLD_RELOC |
| ELF_MACHINE_BEFORE_RTLD_RELOC (main_map, main_map->l_info); |
| diff --git a/elf/get-dynamic-info.h b/elf/get-dynamic-info.h |
| index 1ac0663d1ff5de24..f63e07dc6d2cd5e6 100644 |
| |
| |
| @@ -26,7 +26,8 @@ |
| #include <libc-diag.h> |
| |
| static inline void __attribute__ ((unused, always_inline)) |
| -elf_get_dynamic_info (struct link_map *l) |
| +elf_get_dynamic_info (struct link_map *l, bool bootstrap, |
| + bool static_pie_bootstrap) |
| { |
| #if __ELF_NATIVE_CLASS == 32 |
| typedef Elf32_Word d_tag_utype; |
| @@ -35,7 +36,7 @@ elf_get_dynamic_info (struct link_map *l) |
| #endif |
| |
| #ifndef STATIC_PIE_BOOTSTRAP |
| - if (l->l_ld == NULL) |
| + if (!bootstrap && l->l_ld == NULL) |
| return; |
| #endif |
| |
| @@ -112,47 +113,63 @@ elf_get_dynamic_info (struct link_map *l) |
| if (info[DT_REL] != NULL) |
| assert (info[DT_RELENT]->d_un.d_val == sizeof (ElfW(Rel))); |
| #endif |
| -#ifdef STATIC_PIE_BOOTSTRAP |
| - assert (info[DT_RUNPATH] == NULL); |
| - assert (info[DT_RPATH] == NULL); |
| -#endif |
| - if (info[DT_FLAGS] != NULL) |
| + if (bootstrap || static_pie_bootstrap) |
| { |
| - /* Flags are used. Translate to the old form where available. |
| - Since these l_info entries are only tested for NULL pointers it |
| - is ok if they point to the DT_FLAGS entry. */ |
| - l->l_flags = info[DT_FLAGS]->d_un.d_val; |
| - |
| - if (l->l_flags & DF_SYMBOLIC) |
| - info[DT_SYMBOLIC] = info[DT_FLAGS]; |
| - if (l->l_flags & DF_TEXTREL) |
| - info[DT_TEXTREL] = info[DT_FLAGS]; |
| - if (l->l_flags & DF_BIND_NOW) |
| - info[DT_BIND_NOW] = info[DT_FLAGS]; |
| + assert (info[DT_RUNPATH] == NULL); |
| + assert (info[DT_RPATH] == NULL); |
| } |
| - if (info[VERSYMIDX (DT_FLAGS_1)] != NULL) |
| + if (bootstrap) |
| { |
| - l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val; |
| - if (l->l_flags_1 & DF_1_NODELETE) |
| - l->l_nodelete_pending = true; |
| - |
| - /* Only DT_1_SUPPORTED_MASK bits are supported, and we would like |
| - to assert this, but we can't. Users have been setting |
| - unsupported DF_1_* flags for a long time and glibc has ignored |
| - them. Therefore to avoid breaking existing applications the |
| - best we can do is add a warning during debugging with the |
| - intent of notifying the user of the problem. */ |
| - if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0) |
| - && l->l_flags_1 & ~DT_1_SUPPORTED_MASK) |
| - _dl_debug_printf ("\nWARNING: Unsupported flag value(s) of 0x%x in DT_FLAGS_1.\n", |
| - l->l_flags_1 & ~DT_1_SUPPORTED_MASK); |
| - |
| - if (l->l_flags_1 & DF_1_NOW) |
| - info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)]; |
| + /* Only the bind now flags are allowed. */ |
| + assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL |
| + || (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0); |
| + /* Flags must not be set for ld.so. */ |
| + assert (info[DT_FLAGS] == NULL |
| + || (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0); |
| } |
| - if (info[DT_RUNPATH] != NULL) |
| - /* If both RUNPATH and RPATH are given, the latter is ignored. */ |
| - info[DT_RPATH] = NULL; |
| + else |
| + { |
| + if (info[DT_FLAGS] != NULL) |
| + { |
| + /* Flags are used. Translate to the old form where available. |
| + Since these l_info entries are only tested for NULL pointers it |
| + is ok if they point to the DT_FLAGS entry. */ |
| + l->l_flags = info[DT_FLAGS]->d_un.d_val; |
| + |
| + if (l->l_flags & DF_SYMBOLIC) |
| + info[DT_SYMBOLIC] = info[DT_FLAGS]; |
| + if (l->l_flags & DF_TEXTREL) |
| + info[DT_TEXTREL] = info[DT_FLAGS]; |
| + if (l->l_flags & DF_BIND_NOW) |
| + info[DT_BIND_NOW] = info[DT_FLAGS]; |
| + } |
| + |
| + if (info[VERSYMIDX (DT_FLAGS_1)] != NULL) |
| + { |
| + l->l_flags_1 = info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val; |
| + if (l->l_flags_1 & DF_1_NODELETE) |
| + l->l_nodelete_pending = true; |
| + |
| + /* Only DT_1_SUPPORTED_MASK bits are supported, and we would like |
| + to assert this, but we can't. Users have been setting |
| + unsupported DF_1_* flags for a long time and glibc has ignored |
| + them. Therefore to avoid breaking existing applications the |
| + best we can do is add a warning during debugging with the |
| + intent of notifying the user of the problem. */ |
| + if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0) |
| + && l->l_flags_1 & ~DT_1_SUPPORTED_MASK) |
| + _dl_debug_printf ("\nWARNING: Unsupported flag value(s) of 0x%x " |
| + "in DT_FLAGS_1.\n", |
| + l->l_flags_1 & ~DT_1_SUPPORTED_MASK); |
| + |
| + if (l->l_flags_1 & DF_1_NOW) |
| + info[DT_BIND_NOW] = info[VERSYMIDX (DT_FLAGS_1)]; |
| + } |
| + |
| + if (info[DT_RUNPATH] != NULL) |
| + /* If both RUNPATH and RPATH are given, the latter is ignored. */ |
| + info[DT_RPATH] = NULL; |
| + } |
| } |
| |
| #endif |
| diff --git a/elf/rtld.c b/elf/rtld.c |
| index 37d28d5a66d7b5d6..ad5ddb2a0ab94e7f 100644 |
| |
| |
| @@ -549,7 +549,7 @@ _dl_start (void *arg) |
| /* Read our own dynamic section and fill in the info array. */ |
| bootstrap_map.l_ld = (void *) bootstrap_map.l_addr + elf_machine_dynamic (); |
| bootstrap_map.l_ld_readonly = DL_RO_DYN_SECTION; |
| - elf_get_dynamic_info (&bootstrap_map); |
| + elf_get_dynamic_info (&bootstrap_map, true, false); |
| |
| #if NO_TLS_OFFSET != 0 |
| bootstrap_map.l_tls_offset = NO_TLS_OFFSET; |
| @@ -1653,7 +1653,7 @@ dl_main (const ElfW(Phdr) *phdr, |
| if (! rtld_is_main) |
| { |
| /* Extract the contents of the dynamic section for easy access. */ |
| - elf_get_dynamic_info (main_map); |
| + elf_get_dynamic_info (main_map, false, false); |
| |
| /* If the main map is libc.so, update the base namespace to |
| refer to this map. If libc.so is loaded later, this happens |
| diff --git a/elf/setup-vdso.h b/elf/setup-vdso.h |
| index f44748bc9858e5fd..3f20578046de76ed 100644 |
| |
| |
| @@ -64,7 +64,7 @@ setup_vdso (struct link_map *main_map __attribute__ ((unused)), |
| l->l_map_end += l->l_addr; |
| l->l_text_end += l->l_addr; |
| l->l_ld = (void *) ((ElfW(Addr)) l->l_ld + l->l_addr); |
| - elf_get_dynamic_info (l); |
| + elf_get_dynamic_info (l, false, false); |
| _dl_setup_hash (l); |
| l->l_relocated = 1; |
| |