[libmultipath] fix segfault in print.c when MAX_LINE_LEN is reached

diff --git a/libmultipath/print.c b/libmultipath/print.c
index 03faf85ab3d2453966728371777defc4460cd342..0a61eb3fee16ee0b2e5b39d0ffc209e82bcc5691 100644 (file)
--- a/libmultipath/print.c
+++ b/libmultipath/print.c
@@ -65,9 +65,12 @@ get_map_layout (struct map_layout * ml, vector mpvec)
        return;
 }
 
-#define TAIL   (line + len - c)
+#define TAIL   (line + len - 1 - c)
 #define PAD(x) while ((int)(c - s) < (x)) *c++ = ' '; s = c
 #define NOPAD  s = c
+#define PRINT(var, size, format, args...)      \
+               fwd = snprintf(var, size, format, ##args); \
+               c += (fwd >= size) ? size : fwd;
 
 int
 snprint_map (char * line, int len, char * format,
@@ -77,8 +80,12 @@ snprint_map (char * line, int len, char * format,
        char * s = line;   /* for padding */
        char * f = format; /* format string cursor */
        int i, j;
+       int fwd;
 
        do {
+               if (!TAIL)
+                       break;
+
                if (*f != '%') {
                        *c++ = *f;
                        NOPAD;
@@ -87,32 +94,33 @@ snprint_map (char * line, int len, char * format,
                f++;
                switch (*f) {
                case 'w':       
-                       if (mpp->alias)
-                               c += snprintf(c, TAIL, "%s", mpp->alias);
-                       else
-                               c += snprintf(c, TAIL, "%s", mpp->wwid);
+                       if (mpp->alias) {
+                               PRINT(c, TAIL, "%s", mpp->alias);
+                       } else {
+                               PRINT(c, TAIL, "%s", mpp->wwid);
+                       }
                        PAD(ml->mapname_len);
                        break;
                case 'd':
-                       c += snprintf(c, TAIL, "dm-%i", mpp->minor);
+                       PRINT(c, TAIL, "dm-%i", mpp->minor);
                        PAD(ml->mapdev_len);
                        break;
                case 'F':
                        if (!mpp->failback_tick) {
-                               c += snprintf(c, TAIL,
-                                             "[no scheduled failback]");
+                               PRINT(c, TAIL, "[no scheduled failback]");
                                NOPAD;
                                break;
                        }
                        i = mpp->failback_tick;
                        j = mpp->pgfailback - mpp->failback_tick;
 
-                       while (i-- > 0)
-                               c += snprintf(c, TAIL, "X");
-                                                                                                       while (j-- > 0)
-                               c += snprintf(c, TAIL, ".");
-
-                       c += sprintf(c, " %i/%i",
+                       while (i-- > 0) {
+                               PRINT(c, TAIL, "X");
+                       }
+                       while (j-- > 0) {
+                               PRINT(c, TAIL, ".");
+                       }
+                       PRINT(c, TAIL, " %i/%i",
                                     mpp->failback_tick, mpp->pgfailback);
                        NOPAD;
                        break;
@@ -120,7 +128,10 @@ snprint_map (char * line, int len, char * format,
                        break;
                }
        } while (*f++);
-       return (c - line - 1);
+
+       line[c - line - 1] = '\n';
+
+       return (c - line);
 }
 
 int
@@ -131,8 +142,12 @@ snprint_path (char * line, int len, char * format, struct path * pp,
        char * s = line;   /* for padding */
        char * f = format; /* format string cursor */
        int i, j;
+       int fwd;
 
        do {
+               if (!TAIL)
+                       break;
+
                if (*f != '%') {
                        *c++ = *f;
                        NOPAD;
@@ -141,41 +156,42 @@ snprint_path (char * line, int len, char * format, struct path * pp,
                f++;
                switch (*f) {
                case 'w':       
-                       c += snprintf(c, TAIL, "%s ", pp->wwid);
+                       PRINT(c, TAIL, "%s ", pp->wwid);
                        NOPAD;
                        break;
                case 'i':
-                       if (pp->sg_id.host_no < 0)
-                               c += snprintf(c, TAIL, "#:#:#:# ");
-                       else
-                               c += snprintf(c, TAIL, "%i:%i:%i:%i",
+                       if (pp->sg_id.host_no < 0) {
+                               PRINT(c, TAIL, "#:#:#:# ");
+                       } else {
+                               PRINT(c, TAIL, "%i:%i:%i:%i",
                                        pp->sg_id.host_no,
                                        pp->sg_id.channel,
                                        pp->sg_id.scsi_id,
                                        pp->sg_id.lun);
+                       }
                        PAD(pl->hbtl_len);
                        break;
                case 'd':
-                       c += snprintf(c, TAIL, "%s", pp->dev);
+                       PRINT(c, TAIL, "%s", pp->dev);
                        PAD(pl->dev_len);
                        break;
                case 'D':
-                       c += snprintf(c, TAIL, "%s", pp->dev_t);
+                       PRINT(c, TAIL, "%s", pp->dev_t);
                        PAD(pl->dev_t_len);
                        break;
                case 'T':
                        switch (pp->state) {
                        case PATH_UP:
-                               c += snprintf(c, TAIL, "[ready]");
+                               PRINT(c, TAIL, "[ready]");
                                break;
                        case PATH_DOWN:
-                               c += snprintf(c, TAIL, "[faulty]");
+                               PRINT(c, TAIL, "[faulty]");
                                break;
                        case PATH_SHAKY:
-                               c += snprintf(c, TAIL, "[shaky]");
+                               PRINT(c, TAIL, "[shaky]");
                                break;
                        case PATH_GHOST:
-                               c += snprintf(c, TAIL, "[ghost]");
+                               PRINT(c, TAIL, "[ghost]");
                                break;
                        default:
                                break;
@@ -185,10 +201,10 @@ snprint_path (char * line, int len, char * format, struct path * pp,
                case 't':
                        switch (pp->dmstate) {
                        case PSTATE_ACTIVE:
-                               c += snprintf(c, TAIL, "[active]");
+                               PRINT(c, TAIL, "[active]");
                                break;
                        case PSTATE_FAILED:
-                               c += snprintf(c, TAIL, "[failed]");
+                               PRINT(c, TAIL, "[failed]");
                                break;
                        default:
                                break;
@@ -196,31 +212,32 @@ snprint_path (char * line, int len, char * format, struct path * pp,
                        NOPAD;
                        break;
                case 'c':
-                       if (pp->claimed && pp->dmstate == PSTATE_UNDEF)
-                               c += snprintf(c, TAIL, "[claimed]");
+                       if (pp->claimed && pp->dmstate == PSTATE_UNDEF) {
+                               PRINT(c, TAIL, "[claimed]");
+                       }
                        NOPAD;
                        break;
                case 's':
-                       c += snprintf(c, TAIL, "%s/%s/%s",
+                       PRINT(c, TAIL, "%s/%s/%s",
                                      pp->vendor_id, pp->product_id, pp->rev);
                        NOPAD;
                        break;
                case 'C':
                        if (!pp->mpp) {
-                               c += snprintf(c, TAIL, "[orphan]");
+                               PRINT(c, TAIL, "[orphan]");
                                NOPAD;
                                break;
                        }
                        i = pp->tick;
                        j = pp->checkint - pp->tick;
 
-                       while (i-- > 0)
-                               c += snprintf(c, TAIL, "X");
-
-                       while (j-- > 0)
-                               c += snprintf(c, TAIL, ".");
-
-                       c += snprintf(c, TAIL, " %i/%i",
+                       while (i-- > 0) {
+                               PRINT(c, TAIL, "X");
+                       }
+                       while (j-- > 0) {
+                               PRINT(c, TAIL, ".");
+                       }
+                       PRINT(c, TAIL, " %i/%i",
                                      pp->tick, pp->checkint);
                        NOPAD;
                        break;
@@ -228,6 +245,9 @@ snprint_path (char * line, int len, char * format, struct path * pp,
                        break;
                }
        } while (*f++);
-       return (c - line - 1);
+
+       line[c - line - 1] = '\n';
+
+       return (c - line);
 }
 

diff --git a/libmultipath/print.h b/libmultipath/print.h
index effcad2c751549a26336a377a76e00e07b751427..f9b8f1c0c922f6301bb770ba145c3a453cfb9ac2 100644 (file)
--- a/libmultipath/print.h
+++ b/libmultipath/print.h
@@ -17,10 +17,10 @@
  * %F : failback countdown
  * %C : checker countdown
  */
-#define PRINT_PATH_LONG      "%w %i %d %D %t%T%c %s\n"
-#define PRINT_PATH_INDENT    " \\_ %i %d %D %t%T%c\n"
-#define PRINT_PATH_CHECKER   "%i %d %D %t%T %C\n"
-#define PRINT_MAP_FAILBACK   "%w %d %F\n"
+#define PRINT_PATH_LONG      "%w %i %d %D %t%T%c %s"
+#define PRINT_PATH_INDENT    " \\_ %i %d %D %t%T%c"
+#define PRINT_PATH_CHECKER   "%i %d %D %t%T %C"
+#define PRINT_MAP_FAILBACK   "%w %d %F"
 
 #define MAX_LINE_LEN 80