Pass variables prefixed with both LD_ and LD_32_ to the run-time linker.

This prevents unintentional execution of programs when running ldd(1) on
32-bit Linux binaries.

PR:		175339, 127276
Suggested by:	kib, rstone
Reviewed by:	kib
MFC after:	2 weeks
This commit is contained in:
markj 2013-08-07 00:28:17 +00:00
parent 44ee260831
commit a11192f9a0

View File

@ -49,12 +49,6 @@ __FBSDID("$FreeBSD$");
#include "extern.h"
#ifdef COMPAT_32BIT
#define LD_ "LD_32_"
#else
#define LD_ "LD_"
#endif
/*
* 32-bit ELF data structures can only be used if the system header[s] declare
* them. There is no official macro for determining whether they are declared,
@ -64,6 +58,16 @@ __FBSDID("$FreeBSD$");
#define ELF32_SUPPORTED
#endif
#define LDD_SETENV(name, value, overwrite) do { \
setenv("LD_" name, value, overwrite); \
setenv("LD_32_" name, value, overwrite); \
} while (0)
#define LDD_UNSETENV(name) do { \
unsetenv("LD_" name); \
unsetenv("LD_32_" name); \
} while (0)
static int is_executable(const char *fname, int fd, int *is_shlib,
int *type);
static void usage(void);
@ -82,7 +86,7 @@ execldd32(char *file, char *fmt1, char *fmt2, int aflag, int vflag)
char *argv[8];
int i, rval, status;
unsetenv(LD_ "TRACE_LOADED_OBJECTS");
LDD_UNSETENV("TRACE_LOADED_OBJECTS");
rval = 0;
i = 0;
argv[i++] = strdup(_PATH_LDD32);
@ -121,7 +125,7 @@ execldd32(char *file, char *fmt1, char *fmt2, int aflag, int vflag)
}
while (i--)
free(argv[i]);
setenv(LD_ "TRACE_LOADED_OBJECTS", "yes", 1);
LDD_SETENV("TRACE_LOADED_OBJECTS", "yes", 1);
return (rval);
}
#endif
@ -210,15 +214,15 @@ main(int argc, char *argv[])
}
/* ld.so magic */
setenv(LD_ "TRACE_LOADED_OBJECTS", "yes", 1);
LDD_SETENV("TRACE_LOADED_OBJECTS", "yes", 1);
if (fmt1 != NULL)
setenv(LD_ "TRACE_LOADED_OBJECTS_FMT1", fmt1, 1);
LDD_SETENV("TRACE_LOADED_OBJECTS_FMT1", fmt1, 1);
if (fmt2 != NULL)
setenv(LD_ "TRACE_LOADED_OBJECTS_FMT2", fmt2, 1);
LDD_SETENV("TRACE_LOADED_OBJECTS_FMT2", fmt2, 1);
setenv(LD_ "TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1);
LDD_SETENV("TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1);
if (aflag)
setenv(LD_ "TRACE_LOADED_OBJECTS_ALL", "1", 1);
LDD_SETENV("TRACE_LOADED_OBJECTS_ALL", "1", 1);
else if (fmt1 == NULL && fmt2 == NULL)
/* Default formats */
printf("%s:\n", *argv);