Commit e3c5cf66 authored by Maria Matejka's avatar Maria Matejka Committed by Maria Matejka
Browse files

Fixed undefined behavior on signals. 

The C11 specification allows only sig_atomic_t and _Atomic variable
access. All other accesses to global variables are undefined behavior.

Using int was probably OK on x86 and x86_64; yet there were some reports
from other architectures (especially some MIPS) that in rare cases,
after issuing SIGHUP, BIRD did strange things.
parent 3cf4d419

sysdep/unix/io.c

+0 −4
Original line number Diff line number Diff line
@@ -2144,10 +2144,6 @@ watchdog_stop(void) 
 *	Main I/O Loop

 */



volatile int async_config_flag;		/* Asynchronous reconfiguration/dump scheduled */

volatile int async_dump_flag;

volatile int async_shutdown_flag;



void

io_init(void)

{

sysdep/unix/main.c

+3 −3
Original line number Diff line number Diff line
@@ -583,9 +583,9 @@ cmd_graceful_restart(void) 
 *	Signals

 */



volatile int async_config_flag;

volatile int async_dump_flag;

volatile int async_shutdown_flag;

volatile sig_atomic_t async_config_flag;

volatile sig_atomic_t async_dump_flag;

volatile sig_atomic_t async_shutdown_flag;



static void

handle_sighup(int sig UNUSED)

sysdep/unix/unix.h

+4 −3
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
#define _BIRD_UNIX_H_



#include <sys/socket.h>

#include <signal.h>



struct pool;

struct iface;
@@ -96,9 +97,9 @@ int sockaddr_read(sockaddr *sa, int af, ip_addr *a, struct iface **ifa, uint *po 
#define SUN_LEN(ptr) ((size_t) (((struct sockaddr_un *) 0)->sun_path) + strlen ((ptr)->sun_path))

#endif



extern volatile int async_config_flag;

extern volatile int async_dump_flag;

extern volatile int async_shutdown_flag;

extern volatile sig_atomic_t async_config_flag;

extern volatile sig_atomic_t async_dump_flag;

extern volatile sig_atomic_t async_shutdown_flag;



void io_init(void);

void io_loop(void);

test/birdtest.c

+5 −0
Original line number Diff line number Diff line
@@ -35,6 +35,11 @@ static int no_fork; 
static int no_timeout;

static int is_terminal;		/* Whether stdout is a live terminal or pipe redirect */



volatile sig_atomic_t async_config_flag;		/* Asynchronous reconfiguration/dump scheduled */

volatile sig_atomic_t async_dump_flag;

volatile sig_atomic_t async_shutdown_flag;





uint bt_verbose;

const char *bt_filename;

const char *bt_test_id;

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