busybox/procps/fuser.c
Denys Vlasenko 217a7f4bf9 fuser: fix inverted access() check. Closes 3799.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-05-29 02:03:38 +02:00

323 lines
6.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* tiny fuser implementation
*
* Copyright 2004 Tony J. White
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
//usage:#define fuser_trivial_usage
//usage: "[OPTIONS] FILE or PORT/PROTO"
//usage:#define fuser_full_usage "\n\n"
//usage: "Find processes which use FILEs or PORTs\n"
//usage: "\nOptions:"
//usage: "\n -m Find processes which use same fs as FILEs"
//usage: "\n -4,-6 Search only IPv4/IPv6 space"
//usage: "\n -s Don't display PIDs"
//usage: "\n -k Kill found processes"
//usage: "\n -SIGNAL Signal to send (default: KILL)"
#include "libbb.h"
#define MAX_LINE 255
#define OPTION_STRING "mks64"
enum {
OPT_MOUNT = (1 << 0),
OPT_KILL = (1 << 1),
OPT_SILENT = (1 << 2),
OPT_IP6 = (1 << 3),
OPT_IP4 = (1 << 4),
};
typedef struct inode_list {
struct inode_list *next;
ino_t inode;
dev_t dev;
} inode_list;
struct globals {
int recursion_depth;
pid_t mypid;
inode_list *inode_list_head;
smallint kill_failed;
int killsig;
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { \
G.mypid = getpid(); \
G.killsig = SIGKILL; \
} while (0)
static void add_inode(const struct stat *st)
{
inode_list **curr = &G.inode_list_head;
while (*curr) {
if ((*curr)->dev == st->st_dev
&& (*curr)->inode == st->st_ino
) {
return;
}
curr = &(*curr)->next;
}
*curr = xzalloc(sizeof(inode_list));
(*curr)->dev = st->st_dev;
(*curr)->inode = st->st_ino;
}
static smallint search_dev_inode(const struct stat *st)
{
inode_list *ilist = G.inode_list_head;
while (ilist) {
if (ilist->dev == st->st_dev) {
if (option_mask32 & OPT_MOUNT)
return 1;
if (ilist->inode == st->st_ino)
return 1;
}
ilist = ilist->next;
}
return 0;
}
enum {
PROC_NET = 0,
PROC_DIR,
PROC_DIR_LINKS,
PROC_SUBDIR_LINKS,
};
static smallint scan_proc_net_or_maps(const char *path, unsigned port)
{
FILE *f;
char line[MAX_LINE + 1], addr[68];
int major, minor, r;
long long uint64_inode;
unsigned tmp_port;
smallint retval;
struct stat statbuf;
const char *fmt;
void *fag, *sag;
f = fopen_for_read(path);
if (!f)
return 0;
if (G.recursion_depth == PROC_NET) {
int fd;
/* find socket dev */
statbuf.st_dev = 0;
fd = socket(AF_INET, SOCK_DGRAM, 0);
if (fd >= 0) {
fstat(fd, &statbuf);
close(fd);
}
fmt = "%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x "
"%*x:%*x %*x:%*x %*x %*d %*d %llu";
fag = addr;
sag = &tmp_port;
} else {
fmt = "%*s %*s %*s %x:%x %llu";
fag = &major;
sag = &minor;
}
retval = 0;
while (fgets(line, MAX_LINE, f)) {
r = sscanf(line, fmt, fag, sag, &uint64_inode);
if (r != 3)
continue;
statbuf.st_ino = uint64_inode;
if (G.recursion_depth == PROC_NET) {
r = strlen(addr);
if (r == 8 && (option_mask32 & OPT_IP6))
continue;
if (r > 8 && (option_mask32 & OPT_IP4))
continue;
if (tmp_port == port)
add_inode(&statbuf);
} else {
if (major != 0 && minor != 0 && statbuf.st_ino != 0) {
statbuf.st_dev = makedev(major, minor);
retval = search_dev_inode(&statbuf);
if (retval)
break;
}
}
}
fclose(f);
return retval;
}
static smallint scan_recursive(const char *path)
{
DIR *d;
struct dirent *d_ent;
smallint stop_scan;
smallint retval;
d = opendir(path);
if (d == NULL)
return 0;
G.recursion_depth++;
retval = 0;
stop_scan = 0;
while (!stop_scan && (d_ent = readdir(d)) != NULL) {
struct stat statbuf;
pid_t pid;
char *subpath;
subpath = concat_subpath_file(path, d_ent->d_name);
if (subpath == NULL)
continue; /* . or .. */
switch (G.recursion_depth) {
case PROC_DIR:
pid = (pid_t)bb_strtou(d_ent->d_name, NULL, 10);
if (errno != 0
|| pid == G.mypid
/* "this PID doesn't use specified FILEs or PORT/PROTO": */
|| scan_recursive(subpath) == 0
) {
break;
}
if (option_mask32 & OPT_KILL) {
if (kill(pid, G.killsig) != 0) {
bb_perror_msg("kill pid %s", d_ent->d_name);
G.kill_failed = 1;
}
}
if (!(option_mask32 & OPT_SILENT))
printf("%s ", d_ent->d_name);
retval = 1;
break;
case PROC_DIR_LINKS:
switch (
index_in_substrings(
"cwd" "\0" "exe" "\0"
"root" "\0" "fd" "\0"
"lib" "\0" "mmap" "\0"
"maps" "\0",
d_ent->d_name
)
) {
enum {
CWD_LINK,
EXE_LINK,
ROOT_LINK,
FD_DIR_LINKS,
LIB_DIR_LINKS,
MMAP_DIR_LINKS,
MAPS,
};
case CWD_LINK:
case EXE_LINK:
case ROOT_LINK:
goto scan_link;
case FD_DIR_LINKS:
case LIB_DIR_LINKS:
case MMAP_DIR_LINKS:
stop_scan = scan_recursive(subpath);
if (stop_scan)
retval = stop_scan;
break;
case MAPS:
stop_scan = scan_proc_net_or_maps(subpath, 0);
if (stop_scan)
retval = stop_scan;
default:
break;
}
break;
case PROC_SUBDIR_LINKS:
scan_link:
if (stat(subpath, &statbuf) < 0)
break;
stop_scan = search_dev_inode(&statbuf);
if (stop_scan)
retval = stop_scan;
default:
break;
}
free(subpath);
}
closedir(d);
G.recursion_depth--;
return retval;
}
int fuser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int fuser_main(int argc UNUSED_PARAM, char **argv)
{
char **pp;
INIT_G();
/* Handle -SIGNAL. Oh my... */
pp = argv;
while (*++pp) {
int sig;
char *arg = *pp;
if (arg[0] != '-')
continue;
if (arg[1] == '-' && arg[2] == '\0') /* "--" */
break;
if ((arg[1] == '4' || arg[1] == '6') && arg[2] == '\0')
continue; /* it's "-4" or "-6" */
sig = get_signum(&arg[1]);
if (sig < 0)
continue;
/* "-SIGNAL" option found. Remove it and bail out */
G.killsig = sig;
do {
pp[0] = arg = pp[1];
pp++;
} while (arg);
break;
}
opt_complementary = "-1"; /* at least one param */
getopt32(argv, OPTION_STRING);
argv += optind;
pp = argv;
while (*pp) {
/* parse net arg */
unsigned port;
char path[sizeof("/proc/net/TCP6")];
strcpy(path, "/proc/net/");
if (sscanf(*pp, "%u/%4s", &port, path + sizeof("/proc/net/")-1) == 2
&& access(path, R_OK) == 0
) {
/* PORT/PROTO */
scan_proc_net_or_maps(path, port);
} else {
/* FILE */
struct stat statbuf;
xstat(*pp, &statbuf);
add_inode(&statbuf);
}
pp++;
}
if (scan_recursive("/proc")) {
if (!(option_mask32 & OPT_SILENT))
bb_putchar('\n');
return G.kill_failed;
}
return EXIT_FAILURE;
}