Re: [PATCH] kernel: debug: kdb: strncpy issue, using strlcpy insteadof strncpy.

From: Chen Gang
Date: Thu May 16 2013 - 07:39:01 EST


Hello Maintainers:

Please help check and apply this patch when you hanve time, thanks.

It is already Acked-by Anton, please see below.

Thanks.


On Wed, Apr 17, 2013 at 05:43:13PM +0800, Chen Gang wrote:
> Hello maintainers:
>
> please help check this patch, when you have time, thanks.
>

The patch looks good. I would add to the description: "..., otherwise the
destination string might end up not being terminted with the NUL, causing
all sorts of misbehaviour."

Acked-by: Anton Vorontsov <anton@xxxxxxxxxx>

Thanks!

> On 2013å04æ07æ 19:03, Chen Gang wrote:
>>
>> cmd_cur and cmd_hist[] are all NUL terminated string.
>> need using strlcpy instead of strncpy.
>>
>> Signed-off-by: Chen Gang <gang.chen@xxxxxxxxxxx>
>> ---
>> kernel/debug/kdb/kdb_main.c | 8 ++++----
>> 1 files changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
>> index 00eb8f7..a2b04d7 100644
>> --- a/kernel/debug/kdb/kdb_main.c
>> +++ b/kernel/debug/kdb/kdb_main.c
>> @@ -1063,12 +1063,12 @@ static int handle_ctrl_cmd(char *cmd)
>> case CTRL_P:
>> if (cmdptr != cmd_tail)
>> cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
>> - strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
>> + strlcpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
>> return 1;
>> case CTRL_N:
>> if (cmdptr != cmd_head)
>> cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
>> - strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
>> + strlcpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
>> return 1;
>> }
>> return 0;
>> @@ -1260,7 +1260,7 @@ do_full_getstr:
>> if (*cmdbuf != '\n') {
>> if (*cmdbuf < 32) {
>> if (cmdptr == cmd_head) {
>> - strncpy(cmd_hist[cmd_head], cmd_cur,
>> + strlcpy(cmd_hist[cmd_head], cmd_cur,
>> CMD_BUFLEN);
>> *(cmd_hist[cmd_head] +
>> strlen(cmd_hist[cmd_head])-1) = '\0';
>> @@ -1270,7 +1270,7 @@ do_full_getstr:
>> cmdbuf = cmd_cur;
>> goto do_full_getstr;
>> } else {
>> - strncpy(cmd_hist[cmd_head], cmd_cur,
>> + strlcpy(cmd_hist[cmd_head], cmd_cur,
>> CMD_BUFLEN);
>> }
>>
>>
>
>
> --
> Chen Gang
>
> Asianux Corporation




--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/