From: Chen Gang <gang.chen@asianux•com>
To: Xue Ying <ying.xue0@gmail•com>
Cc: David Miller <davem@davemloft•net>,
Shan Wei <shanwei88@gmail•com>,
Eric Dumazet <eric.dumazet@gmail•com>,
netdev <netdev@vger•kernel.org>
Subject: Re: [Suggestion] net/tipc: can delete checking: (if_local_len > TIPC_MAX_IF_NAME) || (if_peer_len > TIPC_MAX_IF_NAME)
Date: Tue, 20 Nov 2012 13:25:27 +0800 [thread overview]
Message-ID: <50AB1447.2030003@asianux.com> (raw)
In-Reply-To: <50AB12EE.6050802@gmail.com>
于 2012年11月20日 13:19, Xue Ying 写道:
> Chen Gang wrote:
>> Hello David Miller:
>>
>> at net/tipc/link.c:212,213, we can delete the check (if_local_len > TIPC_MAX_IF_NAME) and (if_peer_len > TIPC_MAX_IF_NAME)
>> for the total buffer length is no more than TIPC_MAX_IF_NAME, already (at line 182..186).
>>
>>
>
> The length of name_copy array is TIPC_MAX_LINK_NAME(i.e, 60) while
> TIPC_MAX_IF_NAME is defined to 16, why does the former is more than the
> latter?
>
> Regards,
> Ying
>
It is my fault. thanks.
Regards,
gchen
>> suggest to modify it, although it is minor.
>>
>> thanks.
>>
>>
>> 167 static int link_name_validate(const char *name,
>> 168 struct tipc_link_name *name_parts)
>> 169 {
>> 170 char name_copy[TIPC_MAX_LINK_NAME];
>> 171 char *addr_local;
>> 172 char *if_local;
>> 173 char *addr_peer;
>> 174 char *if_peer;
>> 175 char dummy;
>> 176 u32 z_local, c_local, n_local;
>> 177 u32 z_peer, c_peer, n_peer;
>> 178 u32 if_local_len;
>> 179 u32 if_peer_len;
>> 180
>> 181 /* copy link name & ensure length is OK */
>> 182 name_copy[TIPC_MAX_LINK_NAME - 1] = 0;
>> 183 /* need above in case non-Posix strncpy() doesn't pad with nulls */
>> 184 strncpy(name_copy, name, TIPC_MAX_LINK_NAME);
>> 185 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0)
>> 186 return 0;
>> 187
>> 188 /* ensure all component parts of link name are present */
>> 189 addr_local = name_copy;
>> 190 if_local = strchr(addr_local, ':');
>> 191 if (if_local == NULL)
>> 192 return 0;
>> 193 *(if_local++) = 0;
>> 194 addr_peer = strchr(if_local, '-');
>> 195 if (addr_peer == NULL)
>> 196 return 0;
>> 197 *(addr_peer++) = 0;
>> 198 if_local_len = addr_peer - if_local;
>> 199 if_peer = strchr(addr_peer, ':');
>> 200 if (if_peer == NULL)
>> 201 return 0;
>> 202 *(if_peer++) = 0;
>> 203 if_peer_len = strlen(if_peer) + 1;
>> 204
>> 205 /* validate component parts of link name */
>> 206 if ((sscanf(addr_local, "%u.%u.%u%c",
>> 207 &z_local, &c_local, &n_local, &dummy) != 3) ||
>> 208 (sscanf(addr_peer, "%u.%u.%u%c",
>> 209 &z_peer, &c_peer, &n_peer, &dummy) != 3) ||
>> 210 (z_local > 255) || (c_local > 4095) || (n_local > 4095) ||
>> 211 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) ||
>> 212 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) ||
>> 213 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME))
>> 214 return 0;
>> 215
>> 216 /* return link name components, if necessary */
>> 217 if (name_parts) {
>> 218 name_parts->addr_local = tipc_addr(z_local, c_local, n_local);
>> 219 strcpy(name_parts->if_local, if_local);
>> 220 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer);
>> 221 strcpy(name_parts->if_peer, if_peer);
>> 222 }
>> 223 return 1;
>> 224 }
>>
>>
>>
>>
>
>
>
--
Chen Gang
Asianux Corporation
next prev parent reply other threads:[~2012-11-20 5:24 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-20 4:08 [Suggestion] net/tipc: can delete checking: (if_local_len > TIPC_MAX_IF_NAME) || (if_peer_len > TIPC_MAX_IF_NAME) Chen Gang
2012-11-20 5:19 ` Xue Ying
2012-11-20 5:25 ` Chen Gang [this message]
2012-11-20 8:47 ` [Suggestion] net/netfilter: strcpy for timeout->name Chen Gang
2012-11-21 11:39 ` Florian Westphal
2012-11-21 12:17 ` Chen Gang
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