isdn/gigaset: fix zero size border case in debug dump
authorTilman Schmidt <tilman@imap.cc>
Mon, 21 Jan 2013 11:57:21 +0000 (11:57 +0000)
committerDavid S. Miller <davem@davemloft.net>
Mon, 21 Jan 2013 22:36:02 +0000 (17:36 -0500)
If subtracting 12 from l leaves zero we'd do a zero size allocation,
leading to an oops later when we try to set the NUL terminator.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/isdn/gigaset/capi.c

index 68452b768da23dc31c5409b113446802476886c2..03a0a01a405451c8a85e0e9b83647c105a710f53 100644 (file)
@@ -248,6 +248,8 @@ static inline void dump_rawmsg(enum debuglevel level, const char *tag,
                CAPIMSG_APPID(data), CAPIMSG_MSGID(data), l,
                CAPIMSG_CONTROL(data));
        l -= 12;
                CAPIMSG_APPID(data), CAPIMSG_MSGID(data), l,
                CAPIMSG_CONTROL(data));
        l -= 12;
+       if (l <= 0)
+               return;
        dbgline = kmalloc(3 * l, GFP_ATOMIC);
        if (!dbgline)
                return;
        dbgline = kmalloc(3 * l, GFP_ATOMIC);
        if (!dbgline)
                return;