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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 /sysdeps/unix/sysv/linux/libc-vdso.h | |
| parent | 57013650f7e796428ac2c0b7512757e99327bfc9 (diff) | |
| download | glibc-1bdda52fe92fd01b424cd6fbb63e3df96a95015c.tar.gz glibc-1bdda52fe92fd01b424cd6fbb63e3df96a95015c.tar.xz glibc-1bdda52fe92fd01b424cd6fbb63e3df96a95015c.zip | |
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 'sysdeps/unix/sysv/linux/libc-vdso.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/libc-vdso.h | 30 |
1 files changed, 1 insertions, 29 deletions
diff --git a/sysdeps/unix/sysv/linux/libc-vdso.h b/sysdeps/unix/sysv/linux/libc-vdso.h index 1d7af16be8..31ceafe9d8 100644 --- a/sysdeps/unix/sysv/linux/libc-vdso.h +++ b/sysdeps/unix/sysv/linux/libc-vdso.h @@ -19,37 +19,9 @@ #ifndef _LIBC_VDSO_H #define _LIBC_VDSO_H -#define VDSO_SYMBOL(__name) __vdso_##__name - /* Adjust the return IFUNC value from a vDSO symbol accordingly required by the ELFv1 ABI. It is used by the architecture to create an ODP entry since the kernel vDSO does not provide it. */ -#ifndef VDSO_IFUNC_RET -# define VDSO_IFUNC_RET(__value) (__value) -#endif +#define VDSO_IFUNC_RET(__value) (__value) -#ifdef HAVE_CLOCK_GETTIME_VSYSCALL -extern int (*VDSO_SYMBOL(clock_gettime)) (clockid_t, struct timespec *) - attribute_hidden; -#endif -#ifdef HAVE_CLOCK_GETTIME64_VSYSCALL -extern int (*VDSO_SYMBOL(clock_gettime64)) (clockid_t, struct __timespec64 *) - attribute_hidden; -#endif -#ifdef HAVE_CLOCK_GETRES_VSYSCALL -extern int (*VDSO_SYMBOL(clock_getres)) (clockid_t, struct timespec *) - attribute_hidden; #endif -#ifdef HAVE_GETTIMEOFDAY_VSYSCALL -extern int (*VDSO_SYMBOL (gettimeofday)) (struct timeval *, void *) - attribute_hidden; -#endif -#ifdef HAVE_GETCPU_VSYSCALL -extern long int (*VDSO_SYMBOL(getcpu)) (unsigned *, unsigned *, void *) - attribute_hidden; -#endif -#ifdef HAVE_TIME_VSYSCALL -extern time_t (*VDSO_SYMBOL(time)) (time_t *) attribute_hidden; -#endif - -#endif /* _LIBC_VDSO_H */ |