[PATCH] gcov: fix memory allocation problem in gcov_info_dup

[Yuan Pengfei]

From: Yuan Pengfei <cool...@qq.com>

If -fprofile-values option is used, ctr->num and sci_ptr->num
may be zero, resulting in zero size and cv_size, which will
cause ENOMEM when opening gcov data files in debugfs.
Signed-off-by: Yuan Pengfei <cool...@qq.com>
---
 kernel/gcov/gcc_3_4.c | 2 +-
 kernel/gcov/gcc_4_7.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/gcov/gcc_3_4.c b/kernel/gcov/gcc_3_4.c
index 27bc88a..1c1f425 100644
--- a/kernel/gcov/gcc_3_4.c
+++ b/kernel/gcov/gcc_3_4.c
@@ -269,7 +269,7 @@ struct gcov_info *gcov_info_dup(struct gcov_info *info)
                dup->counts[i].num = ctr->num;
                dup->counts[i].merge = ctr->merge;
                dup->counts[i].values = vmalloc(size);
-               if (!dup->counts[i].values)
+               if (size && !dup->counts[i].values)
                        goto err_free;
                memcpy(dup->counts[i].values, ctr->values, size);
        }
diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c
index 2c6e463..7465944 100644
--- a/kernel/gcov/gcc_4_7.c
+++ b/kernel/gcov/gcc_4_7.c
@@ -290,7 +290,7 @@ struct gcov_info *gcov_info_dup(struct gcov_info *info)
 
                        dci_ptr->values = vmalloc(cv_size);
 
-                       if (!dci_ptr->values)
+                       if (cv_size && !dci_ptr->values)
                                goto err_free;
 
                        dci_ptr->num = sci_ptr->num;
-- 
1.8.5.3