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Diffstat (limited to 'sysdeps/unix/sysv/linux/dl-osinfo.h')
-rw-r--r--sysdeps/unix/sysv/linux/dl-osinfo.h226
1 files changed, 163 insertions, 63 deletions
diff --git a/sysdeps/unix/sysv/linux/dl-osinfo.h b/sysdeps/unix/sysv/linux/dl-osinfo.h
index abc67fc..3c93218 100644
--- a/sysdeps/unix/sysv/linux/dl-osinfo.h
+++ b/sysdeps/unix/sysv/linux/dl-osinfo.h
@@ -1,5 +1,5 @@
-/* Operating system specific code for generic dynamic loader functions.
- Copyright (C) 2000, 2001, 2002, 2004 Free Software Foundation, Inc.
+/* Operating system specific code for generic dynamic loader functions. Linux.
+ Copyright (C) 2000,2001,2002,2004,2005,2006 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
@@ -18,10 +18,14 @@
02111-1307 USA. */
#include <string.h>
+#include <errno.h>
#include <fcntl.h>
-#include <sys/sysctl.h>
#include <sys/utsname.h>
-#include "kernel-features.h"
+#include <kernel-features.h>
+#include <dl-sysdep.h>
+#include <stdint.h>
+#include <hp-timing.h>
+#include <endian.h>
#ifndef MIN
# define MIN(a,b) (((a)<(b))?(a):(b))
@@ -39,71 +43,167 @@ dl_fatal (const char *str)
}
#endif
+static inline int __attribute__ ((always_inline))
+_dl_discover_osversion (void)
+{
+#if (defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO) && defined SHARED
+ if (GLRO(dl_sysinfo_map) != NULL)
+ {
+ /* If the kernel-supplied DSO contains a note indicating the kernel's
+ version, we don't need to call uname or parse any strings. */
+
+ static const struct
+ {
+ ElfW(Word) vendorlen;
+ ElfW(Word) datalen;
+ ElfW(Word) type;
+ char vendor[8];
+ } expected_note = { sizeof "Linux", sizeof (ElfW(Word)), 0, "Linux" };
+ const ElfW(Phdr) *const phdr = GLRO(dl_sysinfo_map)->l_phdr;
+ const ElfW(Word) phnum = GLRO(dl_sysinfo_map)->l_phnum;
+ for (uint_fast16_t i = 0; i < phnum; ++i)
+ if (phdr[i].p_type == PT_NOTE)
+ {
+ const ElfW(Addr) start = (phdr[i].p_vaddr
+ + GLRO(dl_sysinfo_map)->l_addr);
+ const struct
+ {
+ ElfW(Word) vendorlen;
+ ElfW(Word) datalen;
+ ElfW(Word) type;
+ } *note = (const void *) start;
+ while ((ElfW(Addr)) (note + 1) - start < phdr[i].p_memsz)
+ {
+ if (!memcmp (note, &expected_note, sizeof expected_note))
+ return *(const ElfW(Word) *) ((const void *) note
+ + sizeof expected_note);
+#define ROUND(len) (((len) + sizeof (ElfW(Word)) - 1) & -sizeof (ElfW(Word)))
+ note = ((const void *) (note + 1)
+ + ROUND (note->vendorlen) + ROUND (note->datalen));
+ }
+ }
+ }
+#endif
+
+ char bufmem[64];
+ char *buf = bufmem;
+ unsigned int version;
+ int parts;
+ char *cp;
+ struct utsname uts;
+
+ /* Try the uname system call. */
+ if (__uname (&uts))
+ {
+ /* This was not successful. Now try reading the /proc filesystem. */
+ int fd = __open ("/proc/sys/kernel/osrelease", O_RDONLY);
+ if (fd < 0)
+ return -1;
+ ssize_t reslen = __read (fd, bufmem, sizeof (bufmem));
+ __close (fd);
+ if (reslen <= 0)
+ /* This also didn't work. We give up since we cannot
+ make sure the library can actually work. */
+ return -1;
+ buf[MIN (reslen, (ssize_t) sizeof (bufmem) - 1)] = '\0';
+ }
+ else
+ buf = uts.release;
+
+ /* Now convert it into a number. The string consists of at most
+ three parts. */
+ version = 0;
+ parts = 0;
+ cp = buf;
+ while ((*cp >= '0') && (*cp <= '9'))
+ {
+ unsigned int here = *cp++ - '0';
+
+ while ((*cp >= '0') && (*cp <= '9'))
+ {
+ here *= 10;
+ here += *cp++ - '0';
+ }
-#define DL_SYSDEP_OSCHECK(FATAL) \
+ ++parts;
+ version <<= 8;
+ version |= here;
+
+ if (*cp++ != '.')
+ /* Another part following? */
+ break;
+ }
+
+ if (parts < 3)
+ version <<= 8 * (3 - parts);
+
+ return version;
+}
+
+#define DL_SYSDEP_OSCHECK(FATAL) \
do { \
- /* Test whether the kernel is new enough. This test is only \
- performed if the library is not compiled to run on all \
- kernels. */ \
- if (__LINUX_KERNEL_VERSION > 0) \
- { \
- char bufmem[64]; \
- char *buf = bufmem; \
- unsigned int version; \
- int parts; \
- char *cp; \
- struct utsname uts; \
- \
- /* Try the uname syscall */ \
- if (__uname (&uts)) \
- { \
- /* This was not successful. Now try reading the /proc \
- filesystem. */ \
- ssize_t reslen; \
- int fd = __open ("/proc/sys/kernel/osrelease", O_RDONLY); \
- if (fd == -1 \
- || (reslen = __read (fd, bufmem, sizeof (bufmem))) <= 0) \
- /* This also didn't work. We give up since we cannot \
- make sure the library can actually work. */ \
- FATAL ("FATAL: cannot determine kernel version\n"); \
- __close (fd); \
- buf[MIN (reslen, (ssize_t) sizeof (bufmem) - 1)] = '\0'; \
- } \
- else \
- buf = uts.release; \
+ /* Test whether the kernel is new enough. This test is only performed \
+ if the library is not compiled to run on all kernels. */ \
\
- /* Now convert it into a number. The string consists of at most \
- three parts. */ \
- version = 0; \
- parts = 0; \
- cp = buf; \
- while ((*cp >= '0') && (*cp <= '9')) \
- { \
- unsigned int here = *cp++ - '0'; \
- \
- while ((*cp >= '0') && (*cp <= '9')) \
- { \
- here *= 10; \
- here += *cp++ - '0'; \
- } \
- \
- ++parts; \
- version <<= 8; \
- version |= here; \
- \
- if (*cp++ != '.') \
- /* Another part following? */ \
- break; \
- } \
- \
- if (parts < 3) \
- version <<= 8 * (3 - parts); \
+ int version = _dl_discover_osversion (); \
+ if (__builtin_expect (version >= 0, 1)) \
+ { \
+ if (__builtin_expect (GLRO(dl_osversion) == 0, 1) \
+ || GLRO(dl_osversion) > version) \
+ GLRO(dl_osversion) = version; \
\
/* Now we can test with the required version. */ \
- if (version < __LINUX_KERNEL_VERSION) \
+ if (__LINUX_KERNEL_VERSION > 0 && version < __LINUX_KERNEL_VERSION) \
/* Not sufficent. */ \
FATAL ("FATAL: kernel too old\n"); \
- \
- GLRO(dl_osversion) = version; \
} \
+ else if (__LINUX_KERNEL_VERSION > 0) \
+ FATAL ("FATAL: cannot determine kernel version\n"); \
} while (0)
+
+static inline uintptr_t __attribute__ ((always_inline))
+_dl_setup_stack_chk_guard (void)
+{
+ uintptr_t ret;
+#ifdef ENABLE_STACKGUARD_RANDOMIZE
+ int fd = __open ("/dev/urandom", O_RDONLY);
+ if (fd >= 0)
+ {
+ ssize_t reslen = __read (fd, &ret, sizeof (ret));
+ __close (fd);
+ if (reslen == (ssize_t) sizeof (ret))
+ return ret;
+ }
+#endif
+ ret = 0;
+ unsigned char *p = (unsigned char *) &ret;
+ p[sizeof (ret) - 1] = 255;
+ p[sizeof (ret) - 2] = '\n';
+#ifdef HP_TIMING_NOW
+ hp_timing_t hpt;
+ HP_TIMING_NOW (hpt);
+ hpt = (hpt & 0xffff) << 8;
+ ret ^= hpt;
+#endif
+ uintptr_t stk;
+ /* Avoid GCC being too smart. */
+ asm ("" : "=r" (stk) : "r" (p));
+ stk &= 0x7ffff0;
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+ stk <<= (__WORDSIZE - 23);
+#elif __WORDSIZE == 64
+ stk <<= 31;
+#endif
+ ret ^= stk;
+ /* Avoid GCC being too smart. */
+ p = (unsigned char *) &errno;
+ asm ("" : "=r" (stk) : "r" (p));
+ stk &= 0x7fff00;
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+ stk <<= (__WORDSIZE - 29);
+#else
+ stk >>= 8;
+#endif
+ ret ^= stk;
+ return ret;
+}
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