snprintf() truncation checks were one byte too conservative.

This commit is contained in:
Nicholas J. Kain 2022-02-25 06:11:16 -05:00
parent ba8f674e15
commit 7572e2eb8b
10 changed files with 72 additions and 109 deletions

2
cfg.c
View File

@ -5940,7 +5940,7 @@ void parse_cmdline(int argc, char *argv[])
0, argv[i]); 0, argv[i]);
else else
snl = snprintf(argb + argbl, sizeof argb - argbl, "%s", argv[i]); snl = snprintf(argb + argbl, sizeof argb - argbl, "%s", argv[i]);
if (snl < 0 || (size_t)snl >= sizeof argb) if (snl < 0 || (size_t)snl > sizeof argb)
suicide("error parsing command line option: option too long"); suicide("error parsing command line option: option too long");
argbl += (size_t)snl; argbl += (size_t)snl;
} }

2
cfg.rl
View File

@ -328,7 +328,7 @@ void parse_cmdline(int argc, char *argv[])
0, argv[i]); 0, argv[i]);
else else
snl = snprintf(argb + argbl, sizeof argb - argbl, "%s", argv[i]); snl = snprintf(argb + argbl, sizeof argb - argbl, "%s", argv[i]);
if (snl < 0 || (size_t)snl >= sizeof argb) if (snl < 0 || (size_t)snl > sizeof argb)
suicide("error parsing command line option: option too long"); suicide("error parsing command line option: option too long");
argbl += (size_t)snl; argbl += (size_t)snl;
} }

View File

@ -19,11 +19,8 @@
static void get_duid_path(char *duidfile, size_t dlen) static void get_duid_path(char *duidfile, size_t dlen)
{ {
int splen = snprintf(duidfile, dlen, "%s/DUID", state_dir); int splen = snprintf(duidfile, dlen, "%s/DUID", state_dir);
if (splen < 0) if (splen < 0 || (size_t)splen > dlen)
suicide("%s: snprintf failed; return=%d", __func__, splen); suicide("%s: snprintf failed; return=%d", __func__, splen);
if ((size_t)splen >= dlen)
suicide("%s: snprintf dest buffer too small %d >= %zu",
__func__, splen, sizeof dlen);
} }
static void get_iaid_path(char *iaidfile, size_t ilen, static void get_iaid_path(char *iaidfile, size_t ilen,
@ -37,11 +34,8 @@ static void get_iaid_path(char *iaidfile, size_t ilen,
"%s/IAID-%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x", "%s/IAID-%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x",
state_dir, hwaddr[0], hwaddr[1], hwaddr[2], state_dir, hwaddr[0], hwaddr[1], hwaddr[2],
hwaddr[3], hwaddr[4], hwaddr[5]); hwaddr[3], hwaddr[4], hwaddr[5]);
if (splen < 0) if (splen < 0 || (size_t)splen > ilen)
suicide("%s: snprintf failed; return=%d", __func__, splen); suicide("%s: snprintf failed; return=%d", __func__, splen);
if ((size_t)splen >= ilen)
suicide("%s: snprintf dest buffer too small %d >= %zu",
__func__, splen, sizeof ilen);
} }
static int open_duidfile_read(void) static int open_duidfile_read(void)

View File

@ -42,7 +42,7 @@ static int ifcmd_raw(char *buf, size_t buflen, const char *optname,
int ioptlen = (int)optlen; int ioptlen = (int)optlen;
ssize_t olen = snprintf(buf, buflen, "%s:%.*s;", ssize_t olen = snprintf(buf, buflen, "%s:%.*s;",
optname, ioptlen, optdata); optname, ioptlen, optdata);
if (olen < 0 || (size_t)olen >= buflen) { if (olen < 0 || (size_t)olen > buflen) {
log_line("%s: (%s) '%s' option would truncate, so it was dropped.", log_line("%s: (%s) '%s' option would truncate, so it was dropped.",
client_config.interface, __func__, optname); client_config.interface, __func__, optname);
memset(buf, 0, buflen); memset(buf, 0, buflen);
@ -65,7 +65,7 @@ static int ifcmd_u8(char *buf, size_t buflen, const char *optname,
char numbuf[16]; char numbuf[16];
uint8_t c = optdata[0]; uint8_t c = optdata[0];
ssize_t olen = snprintf(numbuf, sizeof numbuf, "%c", c); ssize_t olen = snprintf(numbuf, sizeof numbuf, "%c", c);
if (olen < 0 || (size_t)olen >= sizeof numbuf) if (olen < 0 || (size_t)olen > sizeof numbuf)
return -1; return -1;
return ifcmd_raw(buf, buflen, optname, numbuf, strlen(numbuf)); return ifcmd_raw(buf, buflen, optname, numbuf, strlen(numbuf));
} }
@ -80,7 +80,7 @@ static int ifcmd_u16(char *buf, size_t buflen, const char *optname,
memcpy(&v, optdata, 2); memcpy(&v, optdata, 2);
v = ntohs(v); v = ntohs(v);
ssize_t olen = snprintf(numbuf, sizeof numbuf, "%hu", v); ssize_t olen = snprintf(numbuf, sizeof numbuf, "%hu", v);
if (olen < 0 || (size_t)olen >= sizeof numbuf) if (olen < 0 || (size_t)olen > sizeof numbuf)
return -1; return -1;
return ifcmd_raw(buf, buflen, optname, numbuf, strlen(numbuf)); return ifcmd_raw(buf, buflen, optname, numbuf, strlen(numbuf));
} }
@ -95,7 +95,7 @@ static int ifcmd_s32(char *buf, size_t buflen, const char *optname,
memcpy(&v, optdata, 4); memcpy(&v, optdata, 4);
v = ntohl(v); v = ntohl(v);
ssize_t olen = snprintf(numbuf, sizeof numbuf, "%d", v); ssize_t olen = snprintf(numbuf, sizeof numbuf, "%d", v);
if (olen < 0 || (size_t)olen >= sizeof numbuf) if (olen < 0 || (size_t)olen > sizeof numbuf)
return -1; return -1;
return ifcmd_raw(buf, buflen, optname, numbuf, strlen(numbuf)); return ifcmd_raw(buf, buflen, optname, numbuf, strlen(numbuf));
} }
@ -123,14 +123,14 @@ static int ifcmd_iplist(char *out, size_t outlen, const char *optname,
inet_ntop(AF_INET, optdata + optoff, ipbuf, sizeof ipbuf); inet_ntop(AF_INET, optdata + optoff, ipbuf, sizeof ipbuf);
ssize_t wc = snprintf(buf + bufoff, sizeof buf, "%s", ipbuf); ssize_t wc = snprintf(buf + bufoff, sizeof buf, "%s", ipbuf);
if (wc < 0 || (size_t)wc >= sizeof buf) if (wc < 0 || (size_t)wc > sizeof buf)
return -1; return -1;
optoff += 4; optoff += 4;
bufoff += (size_t)wc; bufoff += (size_t)wc;
while (optlen >= 4 + optoff) { while (optlen >= 4 + optoff) {
inet_ntop(AF_INET, optdata + optoff, ipbuf, sizeof ipbuf); inet_ntop(AF_INET, optdata + optoff, ipbuf, sizeof ipbuf);
wc = snprintf(buf + bufoff, sizeof buf, ",%s", ipbuf); wc = snprintf(buf + bufoff, sizeof buf, ",%s", ipbuf);
if (wc < 0 || (size_t)wc >= sizeof buf) if (wc < 0 || (size_t)wc > sizeof buf)
return -1; return -1;
optoff += 4; optoff += 4;
bufoff += (size_t)wc; bufoff += (size_t)wc;
@ -270,7 +270,7 @@ static size_t send_client_ip(char *out, size_t olen,
} else { } else {
snlen = snprintf(out, olen, "ip4:%s,%s;", ip, sn); snlen = snprintf(out, olen, "ip4:%s,%s;", ip, sn);
} }
if (snlen < 0 || (size_t)snlen >= olen) { if (snlen < 0 || (size_t)snlen > olen) {
log_line("%s: (%s) ip4 command would truncate so it was dropped.", log_line("%s: (%s) ip4 command would truncate so it was dropped.",
client_config.interface, __func__); client_config.interface, __func__);
memset(out, 0, olen); memset(out, 0, olen);

View File

@ -1189,14 +1189,8 @@ int execute_buffer(const char *newbuf)
ssize_t buflen = snprintf(buf, sizeof buf, "%s%s", cl.ibuf, newbuf); ssize_t buflen = snprintf(buf, sizeof buf, "%s%s", cl.ibuf, newbuf);
memset(cl.ibuf, 0, sizeof cl.ibuf); memset(cl.ibuf, 0, sizeof cl.ibuf);
if (buflen < 0) { if (buflen < 0 || (size_t)buflen > sizeof buf) {
log_line("%s: (%s) snprintf1 failed; your system is broken?", log_line("%s: (%s) snprintf1 failed", client_config.interface, __func__);
client_config.interface, __func__);
return -99;
}
if ((size_t)buflen >= sizeof buf) {
log_line("%s: (%s) input is too long for buffer",
client_config.interface, __func__);
return -99; return -99;
} }
@ -1208,15 +1202,15 @@ int execute_buffer(const char *newbuf)
int cs = 0; int cs = 0;
#line 1212 "ifchd-parse.c" #line 1206 "ifchd-parse.c"
{ {
cs = (int)ifchd_parser_start; cs = (int)ifchd_parser_start;
} }
#line 194 "ifchd-parse.rl" #line 188 "ifchd-parse.rl"
#line 1220 "ifchd-parse.c" #line 1214 "ifchd-parse.c"
{ {
switch ( cs ) { switch ( cs ) {
case 1: case 1:
@ -1519,7 +1513,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 1523 "ifchd-parse.c" #line 1517 "ifchd-parse.c"
goto _st2; goto _st2;
_st2: _st2:
@ -1599,7 +1593,7 @@ int execute_buffer(const char *newbuf)
#line 155 "ifchd-parse.rl" #line 155 "ifchd-parse.rl"
cl.state = STATE_CARRIER; } cl.state = STATE_CARRIER; }
#line 1603 "ifchd-parse.c" #line 1597 "ifchd-parse.c"
{ {
#line 105 "ifchd-parse.rl" #line 105 "ifchd-parse.rl"
@ -1630,7 +1624,7 @@ int execute_buffer(const char *newbuf)
cmdf |= pr; cmdf |= pr;
} }
#line 1634 "ifchd-parse.c" #line 1628 "ifchd-parse.c"
goto _st126; goto _st126;
_ctr39: _ctr39:
@ -1647,7 +1641,7 @@ int execute_buffer(const char *newbuf)
tb[arg_len] = 0; tb[arg_len] = 0;
} }
#line 1651 "ifchd-parse.c" #line 1645 "ifchd-parse.c"
{ {
#line 105 "ifchd-parse.rl" #line 105 "ifchd-parse.rl"
@ -1678,7 +1672,7 @@ int execute_buffer(const char *newbuf)
cmdf |= pr; cmdf |= pr;
} }
#line 1682 "ifchd-parse.c" #line 1676 "ifchd-parse.c"
goto _st126; goto _st126;
_st126: _st126:
@ -1724,7 +1718,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 1728 "ifchd-parse.c" #line 1722 "ifchd-parse.c"
goto _st10; goto _st10;
_st10: _st10:
@ -1773,13 +1767,13 @@ int execute_buffer(const char *newbuf)
#line 144 "ifchd-parse.rl" #line 144 "ifchd-parse.rl"
cl.state = STATE_DNS; } cl.state = STATE_DNS; }
#line 1777 "ifchd-parse.c" #line 1771 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 1783 "ifchd-parse.c" #line 1777 "ifchd-parse.c"
goto _st14; goto _st14;
_ctr115: _ctr115:
@ -1787,13 +1781,13 @@ int execute_buffer(const char *newbuf)
#line 145 "ifchd-parse.rl" #line 145 "ifchd-parse.rl"
cl.state = STATE_LPRSVR; } cl.state = STATE_LPRSVR; }
#line 1791 "ifchd-parse.c" #line 1785 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 1797 "ifchd-parse.c" #line 1791 "ifchd-parse.c"
goto _st14; goto _st14;
_ctr126: _ctr126:
@ -1801,13 +1795,13 @@ int execute_buffer(const char *newbuf)
#line 146 "ifchd-parse.rl" #line 146 "ifchd-parse.rl"
cl.state = STATE_NTPSVR; } cl.state = STATE_NTPSVR; }
#line 1805 "ifchd-parse.c" #line 1799 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 1811 "ifchd-parse.c" #line 1805 "ifchd-parse.c"
goto _st14; goto _st14;
_ctr148: _ctr148:
@ -1815,13 +1809,13 @@ int execute_buffer(const char *newbuf)
#line 147 "ifchd-parse.rl" #line 147 "ifchd-parse.rl"
cl.state = STATE_WINS; } cl.state = STATE_WINS; }
#line 1819 "ifchd-parse.c" #line 1813 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 1825 "ifchd-parse.c" #line 1819 "ifchd-parse.c"
goto _st14; goto _st14;
_st14: _st14:
@ -2044,13 +2038,13 @@ int execute_buffer(const char *newbuf)
#line 150 "ifchd-parse.rl" #line 150 "ifchd-parse.rl"
cl.state = STATE_DOMAIN; } cl.state = STATE_DOMAIN; }
#line 2048 "ifchd-parse.c" #line 2042 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 2054 "ifchd-parse.c" #line 2048 "ifchd-parse.c"
goto _st33; goto _st33;
_ctr53: _ctr53:
@ -2058,13 +2052,13 @@ int execute_buffer(const char *newbuf)
#line 149 "ifchd-parse.rl" #line 149 "ifchd-parse.rl"
cl.state = STATE_HOSTNAME; } cl.state = STATE_HOSTNAME; }
#line 2062 "ifchd-parse.c" #line 2056 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 2068 "ifchd-parse.c" #line 2062 "ifchd-parse.c"
goto _st33; goto _st33;
_st33: _st33:
@ -2086,7 +2080,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 2090 "ifchd-parse.c" #line 2084 "ifchd-parse.c"
goto _st34; goto _st34;
_st34: _st34:
@ -2144,7 +2138,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 2148 "ifchd-parse.c" #line 2142 "ifchd-parse.c"
goto _st39; goto _st39;
_st39: _st39:
@ -2193,13 +2187,13 @@ int execute_buffer(const char *newbuf)
#line 143 "ifchd-parse.rl" #line 143 "ifchd-parse.rl"
cl.state = STATE_IP4SET; } cl.state = STATE_IP4SET; }
#line 2197 "ifchd-parse.c" #line 2191 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 2203 "ifchd-parse.c" #line 2197 "ifchd-parse.c"
goto _st43; goto _st43;
_st43: _st43:
@ -2380,13 +2374,13 @@ int execute_buffer(const char *newbuf)
#line 142 "ifchd-parse.rl" #line 142 "ifchd-parse.rl"
cl.state = STATE_ROUTER; } cl.state = STATE_ROUTER; }
#line 2384 "ifchd-parse.c" #line 2378 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 2390 "ifchd-parse.c" #line 2384 "ifchd-parse.c"
goto _st59; goto _st59;
_st59: _st59:
@ -2481,13 +2475,13 @@ int execute_buffer(const char *newbuf)
#line 154 "ifchd-parse.rl" #line 154 "ifchd-parse.rl"
cl.state = STATE_IPTTL; } cl.state = STATE_IPTTL; }
#line 2485 "ifchd-parse.c" #line 2479 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 2491 "ifchd-parse.c" #line 2485 "ifchd-parse.c"
goto _st67; goto _st67;
_st67: _st67:
@ -2778,7 +2772,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 2782 "ifchd-parse.c" #line 2776 "ifchd-parse.c"
goto _st94; goto _st94;
_st94: _st94:
@ -2822,7 +2816,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 2826 "ifchd-parse.c" #line 2820 "ifchd-parse.c"
goto _st98; goto _st98;
_st98: _st98:
@ -2863,13 +2857,13 @@ int execute_buffer(const char *newbuf)
#line 153 "ifchd-parse.rl" #line 153 "ifchd-parse.rl"
cl.state = STATE_MTU; } cl.state = STATE_MTU; }
#line 2867 "ifchd-parse.c" #line 2861 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 2873 "ifchd-parse.c" #line 2867 "ifchd-parse.c"
goto _st102; goto _st102;
_st102: _st102:
@ -2883,7 +2877,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 2887 "ifchd-parse.c" #line 2881 "ifchd-parse.c"
goto _st103; goto _st103;
_st103: _st103:
@ -2927,7 +2921,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 2931 "ifchd-parse.c" #line 2925 "ifchd-parse.c"
goto _st107; goto _st107;
_st107: _st107:
@ -2989,7 +2983,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 2993 "ifchd-parse.c" #line 2987 "ifchd-parse.c"
goto _st113; goto _st113;
_st113: _st113:
@ -3048,13 +3042,13 @@ int execute_buffer(const char *newbuf)
#line 152 "ifchd-parse.rl" #line 152 "ifchd-parse.rl"
cl.state = STATE_TIMEZONE; } cl.state = STATE_TIMEZONE; }
#line 3052 "ifchd-parse.c" #line 3046 "ifchd-parse.c"
{ {
#line 93 "ifchd-parse.rl" #line 93 "ifchd-parse.rl"
arg_start = p; } arg_start = p; }
#line 3058 "ifchd-parse.c" #line 3052 "ifchd-parse.c"
goto _st119; goto _st119;
_st119: _st119:
@ -3074,7 +3068,7 @@ int execute_buffer(const char *newbuf)
#line 92 "ifchd-parse.rl" #line 92 "ifchd-parse.rl"
cl.state = STATE_NOTHING; } cl.state = STATE_NOTHING; }
#line 3078 "ifchd-parse.c" #line 3072 "ifchd-parse.c"
goto _st121; goto _st121;
_st121: _st121:
@ -3252,7 +3246,7 @@ int execute_buffer(const char *newbuf)
_out: {} _out: {}
} }
#line 195 "ifchd-parse.rl" #line 189 "ifchd-parse.rl"
if (cs == ifchd_parser_error) { if (cs == ifchd_parser_error) {
@ -3263,14 +3257,8 @@ int execute_buffer(const char *newbuf)
if (cmd_start != pe) { if (cmd_start != pe) {
ssize_t ilen = snprintf(cl.ibuf, sizeof cl.ibuf, "%s", cmd_start); ssize_t ilen = snprintf(cl.ibuf, sizeof cl.ibuf, "%s", cmd_start);
if (ilen < 0) { if (ilen < 0 || (size_t)ilen > sizeof buf) {
log_line("%s: (%s) snprintf2 failed; your system is broken?", log_line("%s: (%s) snprintf2 failed", client_config.interface, __func__);
client_config.interface, __func__);
return -99;
}
if ((size_t)ilen >= sizeof buf) {
log_line("%s: (%s) unconsumed input too long for buffer",
client_config.interface, __func__);
return -99; return -99;
} }
} }

View File

@ -173,14 +173,8 @@ int execute_buffer(const char *newbuf)
ssize_t buflen = snprintf(buf, sizeof buf, "%s%s", cl.ibuf, newbuf); ssize_t buflen = snprintf(buf, sizeof buf, "%s%s", cl.ibuf, newbuf);
memset(cl.ibuf, 0, sizeof cl.ibuf); memset(cl.ibuf, 0, sizeof cl.ibuf);
if (buflen < 0) { if (buflen < 0 || (size_t)buflen > sizeof buf) {
log_line("%s: (%s) snprintf1 failed; your system is broken?", log_line("%s: (%s) snprintf1 failed", client_config.interface, __func__);
client_config.interface, __func__);
return -99;
}
if ((size_t)buflen >= sizeof buf) {
log_line("%s: (%s) input is too long for buffer",
client_config.interface, __func__);
return -99; return -99;
} }
@ -202,14 +196,8 @@ int execute_buffer(const char *newbuf)
if (cmd_start != pe) { if (cmd_start != pe) {
ssize_t ilen = snprintf(cl.ibuf, sizeof cl.ibuf, "%s", cmd_start); ssize_t ilen = snprintf(cl.ibuf, sizeof cl.ibuf, "%s", cmd_start);
if (ilen < 0) { if (ilen < 0 || (size_t)ilen > sizeof buf) {
log_line("%s: (%s) snprintf2 failed; your system is broken?", log_line("%s: (%s) snprintf2 failed", client_config.interface, __func__);
client_config.interface, __func__);
return -99;
}
if ((size_t)ilen >= sizeof buf) {
log_line("%s: (%s) unconsumed input too long for buffer",
client_config.interface, __func__);
return -99; return -99;
} }
} }

18
ifchd.c
View File

@ -104,7 +104,7 @@ static int write_resolve_conf(void)
else else
*q++ = '\0'; *q++ = '\0';
ssize_t sl = snprintf(buf, sizeof buf, "%s", p); ssize_t sl = snprintf(buf, sizeof buf, "%s", p);
if (sl < 0 || (size_t)sl >= sizeof buf) { if (sl < 0 || (size_t)sl > sizeof buf) {
log_line("%s: (%s) snprintf failed appending nameservers", log_line("%s: (%s) snprintf failed appending nameservers",
client_config.interface, __func__); client_config.interface, __func__);
} }
@ -125,7 +125,7 @@ static int write_resolve_conf(void)
else else
*q++ = '\0'; *q++ = '\0';
ssize_t sl = snprintf(buf, sizeof buf, "%s", p); ssize_t sl = snprintf(buf, sizeof buf, "%s", p);
if (sl < 0 || (size_t)sl >= sizeof buf) { if (sl < 0 || (size_t)sl > sizeof buf) {
log_line("%s: (%s) snprintf failed appending domains", log_line("%s: (%s) snprintf failed appending domains",
client_config.interface, __func__); client_config.interface, __func__);
} }
@ -191,9 +191,8 @@ int perform_dns(const char *str, size_t len)
return ret; return ret;
} }
ssize_t sl = snprintf(cl.namesvrs, sizeof cl.namesvrs, "%s", str); ssize_t sl = snprintf(cl.namesvrs, sizeof cl.namesvrs, "%s", str);
if (sl < 0 || (size_t)sl >= sizeof cl.namesvrs) { if (sl < 0 || (size_t)sl > sizeof cl.namesvrs) {
log_line("%s: (%s) snprintf failed", log_line("%s: (%s) snprintf failed", client_config.interface, __func__);
client_config.interface, __func__);
} }
ret = write_resolve_conf(); ret = write_resolve_conf();
if (ret >= 0) if (ret >= 0)
@ -233,9 +232,8 @@ int perform_domain(const char *str, size_t len)
return ret; return ret;
} }
ssize_t sl = snprintf(cl.domains, sizeof cl.domains, "%s", str); ssize_t sl = snprintf(cl.domains, sizeof cl.domains, "%s", str);
if (sl < 0 || (size_t)sl >= sizeof cl.domains) { if (sl < 0 || (size_t)sl > sizeof cl.domains) {
log_line("%s: (%s) snprintf failed", log_line("%s: (%s) snprintf failed", client_config.interface, __func__);
client_config.interface, __func__);
} }
ret = write_resolve_conf(); ret = write_resolve_conf();
if (ret == 0) if (ret == 0)
@ -348,13 +346,13 @@ static void setup_resolv_conf(void)
char buf[PATH_MAX]; char buf[PATH_MAX];
ssize_t sl = snprintf(buf, sizeof buf, "%s.head", resolv_conf_d); ssize_t sl = snprintf(buf, sizeof buf, "%s.head", resolv_conf_d);
if (sl < 0 || (size_t)sl >= sizeof buf) if (sl < 0 || (size_t)sl > sizeof buf)
log_line("snprintf failed appending resolv_conf_head; path too long?"); log_line("snprintf failed appending resolv_conf_head; path too long?");
else else
resolv_conf_head_fd = open(buf, O_RDONLY|O_CLOEXEC, 0); resolv_conf_head_fd = open(buf, O_RDONLY|O_CLOEXEC, 0);
sl = snprintf(buf, sizeof buf, "%s.tail", resolv_conf_d); sl = snprintf(buf, sizeof buf, "%s.tail", resolv_conf_d);
if (sl < 0 || (size_t)sl >= sizeof buf) if (sl < 0 || (size_t)sl > sizeof buf)
log_line("snprintf failed appending resolv_conf_tail; path too long?"); log_line("snprintf failed appending resolv_conf_tail; path too long?");
else else
resolv_conf_tail_fd = open(buf, O_RDONLY|O_CLOEXEC, 0); resolv_conf_tail_fd = open(buf, O_RDONLY|O_CLOEXEC, 0);

View File

@ -23,12 +23,9 @@ static void get_leasefile_path(char *leasefile, size_t dlen, char *ifname)
{ {
int splen = snprintf(leasefile, dlen, "%s/LEASE-%s", int splen = snprintf(leasefile, dlen, "%s/LEASE-%s",
state_dir, ifname); state_dir, ifname);
if (splen < 0) if (splen < 0 || (size_t)splen > dlen)
suicide("%s: (%s) snprintf failed; return=%d", suicide("%s: (%s) snprintf failed; return=%d",
client_config.interface, __func__, splen); client_config.interface, __func__, splen);
if ((size_t)splen >= dlen)
suicide("%s: (%s) snprintf dest buffer too small %d >= %zu",
client_config.interface, __func__, splen, sizeof dlen);
} }
void open_leasefile(void) void open_leasefile(void)
@ -52,7 +49,7 @@ static void do_write_leasefile(struct in_addr ipnum)
} }
inet_ntop(AF_INET, &ipnum, ip, sizeof ip); inet_ntop(AF_INET, &ipnum, ip, sizeof ip);
ssize_t olen = snprintf(out, sizeof out, "%s\n", ip); ssize_t olen = snprintf(out, sizeof out, "%s\n", ip);
if (olen < 0 || (size_t)olen >= sizeof ip) { if (olen < 0 || (size_t)olen > sizeof ip) {
log_line("%s: (%s) snprintf failed; return=%zd", log_line("%s: (%s) snprintf failed; return=%zd",
client_config.interface, __func__, olen); client_config.interface, __func__, olen);
return; return;

View File

@ -11,10 +11,8 @@ static inline void copy_cmdarg(char *dest, const char *src,
size_t destlen, const char *argname) size_t destlen, const char *argname)
{ {
ssize_t olen = snprintf(dest, destlen, "%s", src); ssize_t olen = snprintf(dest, destlen, "%s", src);
if (olen < 0) if (olen < 0 || (size_t)olen > destlen)
suicide("snprintf failed on %s; your system is broken?", argname); suicide("snprintf failed on %s", argname);
if ((size_t)olen >= destlen)
suicide("snprintf would truncate %s arg; it's too long", argname);
} }
#endif #endif

View File

@ -143,7 +143,7 @@ static int create_udp_socket(uint32_t ip, uint16_t port, char *iface)
struct ifreq ifr; struct ifreq ifr;
memset(&ifr, 0, sizeof ifr); memset(&ifr, 0, sizeof ifr);
ssize_t sl = snprintf(ifr.ifr_name, sizeof ifr.ifr_name, "%s", iface); ssize_t sl = snprintf(ifr.ifr_name, sizeof ifr.ifr_name, "%s", iface);
if (sl < 0 || (size_t)sl >= sizeof ifr.ifr_name) { if (sl < 0 || (size_t)sl > sizeof ifr.ifr_name) {
log_line("%s: (%s) Set interface name failed.", log_line("%s: (%s) Set interface name failed.",
client_config.interface, __func__); client_config.interface, __func__);
goto out_fd; goto out_fd;