[PATCH 2/5] Zle/computil: do not use strcpy() for overlapping blocks

[Kamil Dudka <kdudka@redhat.com>]

Detected by Coverity:

Error: BUFFER_SIZE (CWE-120):
zsh-5.5.1/Src/Zle/computil.c:564: overlapping_buffer: The source buffer "str->str + 2" potentially overlaps with the destination buffer "str->str", which results in undefined behavior for "strcpy".
zsh-5.5.1/Src/Zle/computil.c:564: remediation: Replace "strcpy(dest, src)" with "memmove(dest, src, strlen(src)+1)".
562|                       str->str = ztrdup(str->str);
563|                   if (hide[1] && str->str[0] == '-' && str->str[1] == '-')
564|->                     strcpy(str->str, str->str + 2);
565|                   else if (str->str[0] == '-' || str->str[0] == '+')
566|                       strcpy(str->str, str->str + 1);

Error: BUFFER_SIZE (CWE-120):
zsh-5.5.1/Src/Zle/computil.c:566: overlapping_buffer: The source buffer "str->str + 1" potentially overlaps with the destination buffer "str->str", which results in undefined behavior for "strcpy".
zsh-5.5.1/Src/Zle/computil.c:566: remediation: Replace "strcpy(dest, src)" with "memmove(dest, src, strlen(src)+1)".
564|                       strcpy(str->str, str->str + 2);
565|                   else if (str->str[0] == '-' || str->str[0] == '+')
566|->                     strcpy(str->str, str->str + 1);
567|               }
568|           }
---
 Src/Zle/computil.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Src/Zle/computil.c b/Src/Zle/computil.c
index 5526e0ad0..cb1c01042 100644
--- a/Src/Zle/computil.c
+++ b/Src/Zle/computil.c
@@ -561,9 +561,9 @@ cd_init(char *nam, char *hide, char *mlen, char *sep,
                 if (str->str == str->match)
                     str->str = ztrdup(str->str);
                 if (hide[1] && str->str[0] == '-' && str->str[1] == '-')
-                    strcpy(str->str, str->str + 2);
+                    memmove(str->str, str->str + 2, strlen(str->str) - 1);
                 else if (str->str[0] == '-' || str->str[0] == '+')
-                    strcpy(str->str, str->str + 1);
+                    memmove(str->str, str->str + 1, strlen(str->str));
             }
         }
 	for (ap = args; *args &&
-- 
2.17.2