From c0d6f2a33e1229a96d5d5064b9b04d7d3cd41d9d Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Tue, 10 Nov 2015 19:44:48 -0800 Subject: [PATCH] NaCl: Use open_resource API for shared objects --- ChangeLog | 13 +++++++++ elf/dl-load.c | 44 ++++++++++++++++++++++++----- elf/dl-sysdep-open.h | 45 ++++++++++++++++++++++++++++++ sysdeps/nacl/dl-sysdep-open.h | 40 ++++++++++++++++++++++++++ sysdeps/nacl/dl-sysdep.c | 23 +++++++++++++++ sysdeps/nacl/nacl-interface-list.h | 2 +- 6 files changed, 159 insertions(+), 8 deletions(-) create mode 100644 elf/dl-sysdep-open.h create mode 100644 sysdeps/nacl/dl-sysdep-open.h diff --git a/ChangeLog b/ChangeLog index b23297b29b..39cc8db862 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,16 @@ +2015-11-10 Roland McGrath + + * elf/dl-load.c (open_verify): Take new argument FD. + Skip __open call if passed FD is not -1. + (_dl_map_object, open_path): Update callers. + * elf/dl-sysdep-open.h: New file. + * elf/dl-load.c: Include it. + (_dl_map_object): Try _dl_sysdep_open_object before ldconfig cache. + * sysdeps/nacl/dl-sysdep.c (_dl_sysdep_open_object): New function. + * sysdeps/nacl/dl-sysdep-open.h: New file. + * sysdeps/nacl/nacl-interface-list.h: Move nacl_irt_resource_open + from libc to rtld. + 2015-11-10 Joseph Myers [BZ #19228] diff --git a/elf/dl-load.c b/elf/dl-load.c index c5e948e7e0..6fb615e672 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -43,6 +43,7 @@ #include #include #include +#include #include @@ -1483,9 +1484,13 @@ print_search_path (struct r_search_path_elem **list, ignore only ELF files for other architectures. Non-ELF files and ELF files with different header information cause fatal errors since this could mean there is something wrong in the installation and the - user might want to know about this. */ + user might want to know about this. + + If FD is not -1, then the file is already open and FD refers to it. + In that case, FD is consumed for both successful and error returns. */ static int -open_verify (const char *name, struct filebuf *fbp, struct link_map *loader, +open_verify (const char *name, int fd, + struct filebuf *fbp, struct link_map *loader, int whatcode, int mode, bool *found_other_class, bool free_name) { /* This is the expected ELF header. */ @@ -1526,6 +1531,7 @@ open_verify (const char *name, struct filebuf *fbp, struct link_map *loader, if (__glibc_unlikely (GLRO(dl_naudit) > 0) && whatcode != 0 && loader->l_auditing == 0) { + const char *original_name = name; struct audit_ifaces *afct = GLRO(dl_audit); for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt) { @@ -1540,11 +1546,21 @@ open_verify (const char *name, struct filebuf *fbp, struct link_map *loader, afct = afct->next; } + + if (fd != -1 && name != original_name && strcmp (name, original_name)) + { + /* An audit library changed what we're supposed to open, + so FD no longer matches it. */ + __close (fd); + fd = -1; + } } #endif - /* Open the file. We always open files read-only. */ - int fd = __open (name, O_RDONLY | O_CLOEXEC); + if (fd == -1) + /* Open the file. We always open files read-only. */ + fd = __open (name, O_RDONLY | O_CLOEXEC); + if (fd != -1) { ElfW(Ehdr) *ehdr; @@ -1813,7 +1829,7 @@ open_path (const char *name, size_t namelen, int mode, if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_LIBS)) _dl_debug_printf (" trying file=%s\n", buf); - fd = open_verify (buf, fbp, loader, whatcode, mode, + fd = open_verify (buf, -1, fbp, loader, whatcode, mode, found_other_class, false); if (this_dir->status[cnt] == unknown) { @@ -2064,6 +2080,20 @@ _dl_map_object (struct link_map *loader, const char *name, &loader->l_runpath_dirs, &realname, &fb, loader, LA_SER_RUNPATH, &found_other_class); + if (fd == -1) + { + realname = _dl_sysdep_open_object (name, namelen, &fd); + if (realname != NULL) + { + fd = open_verify (realname, fd, + &fb, loader ?: GL(dl_ns)[nsid]._ns_loaded, + LA_SER_CONFIG, mode, &found_other_class, + false); + if (fd == -1) + free (realname); + } + } + #ifdef USE_LDCONFIG if (fd == -1 && (__glibc_likely ((mode & __RTLD_SECURE) == 0) @@ -2109,7 +2139,7 @@ _dl_map_object (struct link_map *loader, const char *name, if (cached != NULL) { - fd = open_verify (cached, + fd = open_verify (cached, -1, &fb, loader ?: GL(dl_ns)[nsid]._ns_loaded, LA_SER_CONFIG, mode, &found_other_class, false); @@ -2144,7 +2174,7 @@ _dl_map_object (struct link_map *loader, const char *name, fd = -1; else { - fd = open_verify (realname, &fb, + fd = open_verify (realname, -1, &fb, loader ?: GL(dl_ns)[nsid]._ns_loaded, 0, mode, &found_other_class, true); if (__glibc_unlikely (fd == -1)) diff --git a/elf/dl-sysdep-open.h b/elf/dl-sysdep-open.h new file mode 100644 index 0000000000..a63d9f5f78 --- /dev/null +++ b/elf/dl-sysdep-open.h @@ -0,0 +1,45 @@ +/* System-specific call to open a shared object by name. Stub version. + Copyright (C) 2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _DL_SYSDEP_OPEN_H +#define _DL_SYSDEP_OPEN_H 1 + +#include +#include + +/* NAME is a name without slashes, as it appears in a DT_NEEDED entry + or a dlopen call's argument or suchlike. NAMELEN is (strlen (NAME) + 1). + + Find NAME in an OS-dependent fashion, and return its "real" name. + Optionally fill in *FD with a file descriptor open on that file (or + else leave its initial value of -1). The return value is a new + malloc'd string, which will be free'd by the caller. If NAME is + resolved to an actual file that can be opened, then the return + value should name that file (and if *FD was not set, then a normal + __open call on that string will be made). If *FD was set by some + other means than a normal open and there is no "real" name to use, + then __strdup (NAME) is fine (modulo error checking). */ + +static inline char * +_dl_sysdep_open_object (const char *name, size_t namelen, int *fd) +{ + assert (*fd == -1); + return NULL; +} + +#endif /* dl-sysdep-open.h */ diff --git a/sysdeps/nacl/dl-sysdep-open.h b/sysdeps/nacl/dl-sysdep-open.h new file mode 100644 index 0000000000..38b0f9e86d --- /dev/null +++ b/sysdeps/nacl/dl-sysdep-open.h @@ -0,0 +1,40 @@ +/* System-specific call to open a shared object by name. NaCl version. + Copyright (C) 2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _DL_SYSDEP_OPEN_H +#define _DL_SYSDEP_OPEN_H 1 + +#include + +/* NAME is a name without slashes, as it appears in a DT_NEEDED entry + or a dlopen call's argument or suchlike. NAMELEN is (strlen (NAME) + 1). + + Find NAME in an OS-dependent fashion, and return its "real" name. + Optionally fill in *FD with a file descriptor open on that file (or + else leave its initial value of -1). The return value is a new + malloc'd string, which will be free'd by the caller. If NAME is + resolved to an actual file that can be opened, then the return + value should name that file (and if *FD was not set, then a normal + __open call on that string will be made). If *FD was set by some + other means than a normal open and there is no "real" name to use, + then __strdup (NAME) is fine (modulo error checking). */ + +extern char *_dl_sysdep_open_object (const char *name, size_t namelen, int *fd) + internal_function attribute_hidden; + +#endif /* dl-sysdep-open.h */ diff --git a/sysdeps/nacl/dl-sysdep.c b/sysdeps/nacl/dl-sysdep.c index 3e902c2cae..3a04aa1176 100644 --- a/sysdeps/nacl/dl-sysdep.c +++ b/sysdeps/nacl/dl-sysdep.c @@ -87,3 +87,26 @@ _dl_start_user (void (*user_entry) (uint32_t info[]), uint32_t info[]) #endif /* SHARED */ #include + +#include +#include +#include +#include +#include + +char * +internal_function +_dl_sysdep_open_object (const char *name, size_t namelen, int *fd) +{ + int error = __nacl_irt_resource_open.open_resource (name, fd); + if (error) + return NULL; + assert (*fd != -1); + char *realname = __strdup (name); + if (__glibc_unlikely (realname == NULL)) + { + __close (*fd); + *fd = -1; + } + return realname; +} diff --git a/sysdeps/nacl/nacl-interface-list.h b/sysdeps/nacl/nacl-interface-list.h index cb337510fc..c68faedc54 100644 --- a/sysdeps/nacl/nacl-interface-list.h +++ b/sysdeps/nacl/nacl-interface-list.h @@ -28,7 +28,7 @@ NACL_MANDATORY_INTERFACE (rtld, NACL_IRT_FUTEX_v0_1, nacl_irt_futex) NACL_MANDATORY_INTERFACE (rtld, NACL_IRT_TLS_v0_1, nacl_irt_tls) -NACL_MANDATORY_INTERFACE (libc, +NACL_MANDATORY_INTERFACE (rtld, NACL_IRT_RESOURCE_OPEN_v0_1, nacl_irt_resource_open) NACL_MANDATORY_INTERFACE (rtld, NACL_IRT_CODE_DATA_ALLOC_v0_1,