isdn: Partially revert debug format string usage clean up

Commit 35a4a57 ("isdn: clean up debug format string usage") introduced
a safeguard to avoid accidential format string interpolation of data
when calling debugl1 or HiSax_putstatus. This did however not take into
account VHiSax_putstatus (called by HiSax_putstatus) does *not* call
vsprintf if the head parameter is NULL - the format string is treated
as plain text then instead. As a result, the string "%s" is processed
literally, and the actual information is lost. This affects the isdnlog
userspace program which stopped logging information since that commit.

So revert the HiSax_putstatus invocations to the previous state.

Fixes: 35a4a5733b0a ("isdn: clean up debug format string usage")
Cc: Kees Cook <keescook@chromium.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Signed-off-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 6 insertions, 6 deletions

diff --git a/drivers/isdn/hisax/config.c b/drivers/isdn/hisax/config.c
index b33f53b3ca93..bf04d2a3cf4a 100644
--- a/drivers/isdn/hisax/config.c
+++ b/drivers/isdn/hisax/config.c
@@ -1896,7 +1896,7 @@ static void EChannel_proc_rcv(struct hisax_d_if *d_if)
                                 ptr--;
                                 *ptr++ = '\n';
                                 *ptr = 0;
-                                HiSax_putstatus(cs, NULL, "%s", cs->dlog);
+                                HiSax_putstatus(cs, NULL, cs->dlog);
                         } else
                                 HiSax_putstatus(cs, "LogEcho: ",
                                                 "warning Frame too big (%d)",
diff --git a/drivers/isdn/hisax/hfc_pci.c b/drivers/isdn/hisax/hfc_pci.c
index 4a4825528188..90449e1e91e5 100644
--- a/drivers/isdn/hisax/hfc_pci.c
+++ b/drivers/isdn/hisax/hfc_pci.c
@@ -901,7 +901,7 @@ Begin:
                                         ptr--;
                                         *ptr++ = '\n';
                                         *ptr = 0;
-                                        HiSax_putstatus(cs, NULL, "%s", cs->dlog);
+                                        HiSax_putstatus(cs, NULL, cs->dlog);
                                 } else
                                         HiSax_putstatus(cs, "LogEcho: ", "warning Frame too big (%d)", total - 3);
                         }
diff --git a/drivers/isdn/hisax/hfc_sx.c b/drivers/isdn/hisax/hfc_sx.c
index b1fad81f0722..13b2151c10f5 100644
--- a/drivers/isdn/hisax/hfc_sx.c
+++ b/drivers/isdn/hisax/hfc_sx.c
@@ -674,7 +674,7 @@ receive_emsg(struct IsdnCardState *cs)
                                         ptr--;
                                         *ptr++ = '\n';
                                         *ptr = 0;
-                                        HiSax_putstatus(cs, NULL, "%s", cs->dlog);
+                                        HiSax_putstatus(cs, NULL, cs->dlog);
                                 } else
                                         HiSax_putstatus(cs, "LogEcho: ", "warning Frame too big (%d)", skb->len);
                         }
diff --git a/drivers/isdn/hisax/q931.c b/drivers/isdn/hisax/q931.c
index b420f8bd862e..ba4beb25d872 100644
--- a/drivers/isdn/hisax/q931.c
+++ b/drivers/isdn/hisax/q931.c
@@ -1179,7 +1179,7 @@ LogFrame(struct IsdnCardState *cs, u_char *buf, int size)
                 dp--;
                 *dp++ = '\n';
                 *dp = 0;
-                HiSax_putstatus(cs, NULL, "%s", cs->dlog);
+                HiSax_putstatus(cs, NULL, cs->dlog);
         } else
                 HiSax_putstatus(cs, "LogFrame: ", "warning Frame too big (%d)", size);
 }
@@ -1246,7 +1246,7 @@ dlogframe(struct IsdnCardState *cs, struct sk_buff *skb, int dir)
         }
         if (finish) {
                 *dp = 0;
-                HiSax_putstatus(cs, NULL, "%s", cs->dlog);
+                HiSax_putstatus(cs, NULL, cs->dlog);
                 return;
         }
         if ((0xfe & buf[0]) == PROTO_DIS_N0) {  /* 1TR6 */
@@ -1509,5 +1509,5 @@ dlogframe(struct IsdnCardState *cs, struct sk_buff *skb, int dir)
                 dp += sprintf(dp, "Unknown protocol %x!", buf[0]);
         }
         *dp = 0;
-        HiSax_putstatus(cs, NULL, "%s", cs->dlog);
+        HiSax_putstatus(cs, NULL, cs->dlog);
 }