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| author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2019-11-29 10:44:59 -0300 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2020-01-03 11:22:07 -0300 |
| commit | 1bdda52fe92fd01b424cd6fbb63e3df96a95015c (patch) | |
| tree | d25214e63bf5c96ab48c11ec0df28b5d96ca99da /elf | |
| parent | 57013650f7e796428ac2c0b7512757e99327bfc9 (diff) | |
| download | glibc-1bdda52fe92fd01b424cd6fbb63e3df96a95015c.tar.gz | |
elf: Move vDSO setup to rtld (BZ#24967)
This patch moves the vDSO setup from libc to loader code, just after
the vDSO link_map setup. For static case the initialization
is moved to _dl_non_dynamic_init instead.
Instead of using the mangled pointer, the vDSO data is set as
attribute_relro (on _rtld_global_ro for shared or _dl_vdso_* for
static). It is read-only even with partial relro.
It fixes BZ#24967 now that the vDSO pointer is setup earlier than
malloc interposition is called.
Also, vDSO calls should not be a problem for static dlopen as
indicated by BZ#20802. The vDSO pointer would be zero-initialized
and the syscall will be issued instead.
Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
arm-linux-gnueabihf, powerpc64le-linux-gnu, powerpc64-linux-gnu,
powerpc-linux-gnu, s390x-linux-gnu, sparc64-linux-gnu, and
sparcv9-linux-gnu. I also run some tests on mips.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/dl-support.c | 7 | ||||
| -rw-r--r-- | elf/rtld.c | 7 |
2 files changed, 13 insertions, 1 deletions
diff --git a/elf/dl-support.c b/elf/dl-support.c index 508a5c1196..ad791ab6ab 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -34,6 +34,8 @@ #include <unsecvars.h> #include <hp-timing.h> #include <stackinfo.h> +#include <dl-vdso.h> +#include <dl-vdso-setup.h> extern char *__progname; char **_dl_argv = &__progname; /* This is checked for some error messages. */ @@ -201,6 +203,8 @@ struct link_map *_dl_sysinfo_map; # include "get-dynamic-info.h" #endif #include "setup-vdso.h" +/* Define the vDSO function pointers. */ +#include <dl-vdso-setup.c> /* During the program run we must not modify the global data of loaded shared object simultanously in two threads. Therefore we @@ -315,6 +319,9 @@ _dl_non_dynamic_init (void) so they can influence _dl_init_paths. */ setup_vdso (NULL, NULL); + /* With vDSO setup we can initialize the function pointers. */ + setup_vdso_pointers (); + /* Initialize the data structures for the search paths for shared objects. */ _dl_init_paths (getenv ("LD_LIBRARY_PATH")); diff --git a/elf/rtld.c b/elf/rtld.c index 817fb86eac..553cfbd1b7 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -39,6 +39,8 @@ #include <dl-osinfo.h> #include <dl-procinfo.h> #include <dl-prop.h> +#include <dl-vdso.h> +#include <dl-vdso-setup.h> #include <tls.h> #include <stap-probe.h> #include <stackinfo.h> @@ -833,7 +835,7 @@ security_init (void) _dl_random = NULL; } -#include "setup-vdso.h" +#include <setup-vdso.h> /* The library search path. */ static const char *library_path attribute_relro; @@ -1538,6 +1540,9 @@ ERROR: '%s': cannot process note segment.\n", _dl_argv[0]); so they can influence _dl_init_paths. */ setup_vdso (main_map, &first_preload); + /* With vDSO setup we can initialize the function pointers. */ + setup_vdso_pointers (); + #ifdef DL_SYSDEP_OSCHECK DL_SYSDEP_OSCHECK (_dl_fatal_printf); #endif |