diff options
Diffstat (limited to 'sysdeps/generic/libc-start.c')
| -rw-r--r-- | sysdeps/generic/libc-start.c | 43 |
1 files changed, 7 insertions, 36 deletions
diff --git a/sysdeps/generic/libc-start.c b/sysdeps/generic/libc-start.c index fe4966cd46..f5486f91e1 100644 --- a/sysdeps/generic/libc-start.c +++ b/sysdeps/generic/libc-start.c @@ -16,12 +16,8 @@ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -#include <errno.h> -#include <fcntl.h> -#include <paths.h> #include <stdlib.h> #include <unistd.h> -#include <sys/ioctl.h> #include <ldsodefs.h> extern void __libc_init_first (int argc, char **argv, char **envp); @@ -32,7 +28,7 @@ extern int __libc_multiple_libcs; extern void *__libc_stack_end; /* Prototype for local function. */ -static void check_standard_fds (void); +extern void __libc_check_standard_fds (void); int __libc_start_main (int (*main) (int, char **, char **), int argc, @@ -54,10 +50,14 @@ __libc_start_main (int (*main) (int, char **, char **), int argc, /* Set the global _environ variable correctly. */ __environ = &argv[argc + 1]; +#ifndef SHARED /* Some security at this point. Prevent starting a SUID binary where - the standard file descriptors are not opened. */ + the standard file descriptors are not opened. We have to do this + only for statically linked applications since otherwise the dynamic + loader did the work already. */ if (__builtin_expect (__libc_enable_secure, 0)) - check_standard_fds (); + __libc_check_standard_fds (); +#endif /* Register the destructor of the dynamic linker if there is any. */ if (__builtin_expect (rtld_fini != NULL, 1)) @@ -89,32 +89,3 @@ __libc_start_main (int (*main) (int, char **, char **), int argc, exit ((*main) (argc, argv, __environ)); } - - -/* Should other OSes (e.g., Hurd) have different versions which can - be written in a better way? */ -static void -check_one_fd (int fd, int mode) -{ - if (__libc_fcntl (fd, F_GETFD) == -1 && errno == EBADF) - { - /* Something is wrong with this descriptor, it's probably not - opened. Open /dev/null so that the SUID program we are - about to start does not accidently use this descriptor. */ - int nullfd = __libc_open (_PATH_DEVNULL, mode); - if (nullfd == -1) - /* We cannot even give an error message here since it would - run into the same problems. */ - abort (); - } -} - - -static void -check_standard_fds (void) -{ -/* Check all three standard file descriptors. */ - check_one_fd (STDIN_FILENO, O_RDONLY); - check_one_fd (STDOUT_FILENO, O_RDWR); - check_one_fd (STDERR_FILENO, O_RDWR); -} |