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>

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 6d43839..954ca21 100644 (file)
--- 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 ab54929..e7ff0d0 100644 (file)
--- 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 e443e69..b4c9365 100644 (file)
--- 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);
                        }
                }