diff options
Diffstat (limited to 'sysdeps/unix/sysv')
| -rw-r--r-- | sysdeps/unix/sysv/linux/dl-rseq-symbols.S | 27 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/rseq-internal.h | 16 |
2 files changed, 28 insertions, 15 deletions
diff --git a/sysdeps/unix/sysv/linux/dl-rseq-symbols.S b/sysdeps/unix/sysv/linux/dl-rseq-symbols.S index 353bf65..2502a76 100644 --- a/sysdeps/unix/sysv/linux/dl-rseq-symbols.S +++ b/sysdeps/unix/sysv/linux/dl-rseq-symbols.S @@ -27,14 +27,18 @@ /* Some targets define a macro to denote the zero register. */ #undef zero -/* Define 2 symbols: '__rseq_size' is public const and '_rseq_size' (an - alias of '__rseq_size') is hidden and writable for internal use by the - dynamic linker which will initialize the value both symbols point to - before copy relocations take place. */ +/* Define 3 symbols: '__rseq_size' is public const and then '_rseq_size' and + '__GI___rseq_size' (both aliases of '__rseq_size') are hidden, '_rseq_size' + is writable for internal use by the dynamic linker which will initialize + the value the symbols point to before copy relocations take place. */ .globl __rseq_size .type __rseq_size, %object .size __rseq_size, 4 + .hidden __GI___rseq_size + .globl __GI___rseq_size + .type __GI___rseq_size, %object + .size __GI___rseq_size, 4 .hidden _rseq_size .globl _rseq_size .type _rseq_size, %object @@ -42,17 +46,23 @@ .section .data.rel.ro .balign 4 __rseq_size: +__GI___rseq_size: _rseq_size: .zero 4 -/* Define 2 symbols: '__rseq_offset' is public const and '_rseq_offset' (an - alias of '__rseq_offset') is hidden and writable for internal use by the - dynamic linker which will initialize the value both symbols point to - before copy relocations take place. */ +/* Define 3 symbols: '__rseq_offset' is public const and then '_rseq_offset' + and '__GI___rseq_offset' (both aliases of '__rseq_offset') are hidden, + '_rseq_offset' is writable for internal use by the dynamic linker which will + initialize the value the symbols point to before copy relocations take + place. */ .globl __rseq_offset .type __rseq_offset, %object .size __rseq_offset, RSEQ_OFFSET_SIZE + .hidden __GI___rseq_offset + .globl __GI___rseq_offset + .type __GI___rseq_offset, %object + .size __GI___rseq_offset, RSEQ_OFFSET_SIZE .hidden _rseq_offset .globl _rseq_offset .type _rseq_offset, %object @@ -60,5 +70,6 @@ _rseq_size: .section .data.rel.ro .balign RSEQ_OFFSET_SIZE __rseq_offset: +__GI___rseq_offset: _rseq_offset: .zero RSEQ_OFFSET_SIZE diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h index 6f56558..3993431 100644 --- a/sysdeps/unix/sysv/linux/rseq-internal.h +++ b/sysdeps/unix/sysv/linux/rseq-internal.h @@ -24,6 +24,7 @@ #include <stdbool.h> #include <stdio.h> #include <sys/rseq.h> +#include <ldsodefs.h> /* Minimum size of the rseq area allocation required by the syscall. The actually used rseq feature size may be less (20 bytes initially). */ @@ -52,19 +53,20 @@ extern unsigned int _rseq_size attribute_hidden; In .data.relro but not yet write-protected. */ extern ptrdiff_t _rseq_offset attribute_hidden; +/* We want to use rtld_hidden_proto in order to call the internal aliases + of __rseq_size and __rseq_offset from ld.so. This avoids dynamic symbol + binding at run time for both variables. */ +rtld_hidden_proto (__rseq_size) +rtld_hidden_proto (__rseq_offset) + #ifdef RSEQ_SIG static inline bool rseq_register_current_thread (struct pthread *self, bool do_rseq) { if (do_rseq) { - unsigned int size; -#if IS_IN (rtld) - /* Use the hidden symbol in ld.so. */ - size = _rseq_size; -#else - size = __rseq_size; -#endif + unsigned int size = __rseq_size; + if (size < RSEQ_AREA_SIZE_INITIAL) /* The initial implementation used only 20 bytes out of 32, but still expected size 32. */ |