perf probe: Fix a bug that --line range can be overflow

Since line_finder.lno_s/e are signed int but line_range.start/end
are unsigned int, it is possible to be overflow when converting
line_range->start/end to line_finder->lno_s/e.
This changes line_range.start/end and line_list.line to signed int
and adds overflow checks when setting line_finder.lno_s/e.

LKML-Reference: <20100414223942.14630.72730.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

3 files changed, 24 insertions, 24 deletions

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 6d438391bae5..954ca210e4b7 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -189,7 +189,7 @@ static int try_to_find_kprobe_trace_events(struct perf_probe_event *pev,
 #define LINEBUF_SIZE 256
 #define NR_ADDITIONAL_LINES 2
 
-static int show_one_line(FILE *fp, unsigned int l, bool skip, bool show_num)
+static int show_one_line(FILE *fp, int l, bool skip, bool show_num)
 {
         char buf[LINEBUF_SIZE];
         const char *color = PERF_COLOR_BLUE;
@@ -198,7 +198,7 @@ static int show_one_line(FILE *fp, unsigned int l, bool skip, bool show_num)
                 goto error;
         if (!skip) {
                 if (show_num)
-                        fprintf(stdout, "%7u  %s", l, buf);
+                        fprintf(stdout, "%7d  %s", l, buf);
                 else
                         color_fprintf(stdout, color, "         %s", buf);
         }
@@ -231,7 +231,7 @@ error:
  */
 int show_line_range(struct line_range *lr)
 {
-        unsigned int l = 1;
+        int l = 1;
         struct line_node *ln;
         FILE *fp;
         int fd, ret;
@@ -340,16 +340,15 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
          */
         ptr = strchr(arg, ':');
         if (ptr) {
-                lr->start = (unsigned int)strtoul(ptr + 1, &tmp, 0);
+                lr->start = (int)strtoul(ptr + 1, &tmp, 0);
                 if (*tmp == '+')
-                        lr->end = lr->start + (unsigned int)strtoul(tmp + 1,
-                                                                    &tmp, 0);
+                        lr->end = lr->start + (int)strtoul(tmp + 1, &tmp, 0);
                 else if (*tmp == '-')
-                        lr->end = (unsigned int)strtoul(tmp + 1, &tmp, 0);
+                        lr->end = (int)strtoul(tmp + 1, &tmp, 0);
                 else
-                        lr->end = 0;
-                pr_debug("Line range is %u to %u\n", lr->start, lr->end);
-                if (lr->end && lr->start > lr->end) {
+                        lr->end = INT_MAX;
+                pr_debug("Line range is %d to %d\n", lr->start, lr->end);
+                if (lr->start > lr->end) {
                         semantic_error("Start line must be smaller"
                                        " than end line.\n");
                         return -EINVAL;
@@ -360,8 +359,10 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
                         return -EINVAL;
                 }
                 tmp = strndup(arg, (ptr - arg));
-        } else
+        } else {
                 tmp = strdup(arg);
+                lr->end = INT_MAX;
+        }
 
         if (tmp == NULL)
                 return -ENOMEM;
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index ab5492901708..e7ff0d02c0d4 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -74,15 +74,15 @@ struct perf_probe_event {
 /* Line number container */
 struct line_node {
         struct list_head        list;
-        unsigned int            line;
+        int                     line;
 };
 
 /* Line range */
 struct line_range {
         char                    *file;          /* File name */
         char                    *function;      /* Function name */
-        unsigned int            start;          /* Start line number */
-        unsigned int            end;            /* End line number */
+        int                     start;          /* Start line number */
+        int                     end;            /* End line number */
         int                     offset;         /* Start line offset */
         char                    *path;          /* Real path name */
         struct list_head        line_list;      /* Visible lines */
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index e443e69a4d2e..b4c93659929a 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -111,7 +111,7 @@ static int strtailcmp(const char *s1, const char *s2)
 /* Line number list operations */
 
 /* Add a line to line number list */
-static int line_list__add_line(struct list_head *head, unsigned int line)
+static int line_list__add_line(struct list_head *head, int line)
 {
         struct line_node *ln;
         struct list_head *p;
@@ -138,7 +138,7 @@ found:
 }
 
 /* Check if the line in line number list */
-static int line_list__has_line(struct list_head *head, unsigned int line)
+static int line_list__has_line(struct list_head *head, int line)
 {
         struct line_node *ln;
 
@@ -1146,7 +1146,7 @@ static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
                         if (lf->lr->path == NULL)
                                 return -ENOMEM;
                 }
-                line_list__add_line(&lf->lr->line_list, (unsigned int)lineno);
+                line_list__add_line(&lf->lr->line_list, lineno);
         }
         /* Update status */
         if (!list_empty(&lf->lr->line_list))
@@ -1179,10 +1179,12 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
                 dwarf_decl_line(sp_die, &lr->offset);
                 pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
                 lf->lno_s = lr->offset + lr->start;
-                if (!lr->end)
+                if (lf->lno_s < 0)      /* Overflow */
+                        lf->lno_s = INT_MAX;
+                lf->lno_e = lr->offset + lr->end;
+                if (lf->lno_e < 0)      /* Overflow */
                         lf->lno_e = INT_MAX;
-                else
-                        lf->lno_e = lr->offset + lr->end;
+                pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
                 lr->start = lf->lno_s;
                 lr->end = lf->lno_e;
                 if (dwarf_func_inline(sp_die)) {
@@ -1244,10 +1246,7 @@ int find_line_range(int fd, struct line_range *lr)
                                 ret = find_line_range_by_func(&lf);
                         else {
                                 lf.lno_s = lr->start;
-                                if (!lr->end)
-                                        lf.lno_e = INT_MAX;
-                                else
-                                        lf.lno_e = lr->end;
+                                lf.lno_e = lr->end;
                                 ret = find_line_range_by_line(NULL, &lf);
                         }
                 }