if strlen(s) was 0, it would then end up using s[-1] as an array index. Bad,

bad, bad.  This was crashing the shell on powerpc boxes, though all other archs
seem to have a much more forgiving malloc implementations.  I finally found
this bug using electric-fence on a powerpc box.
 -Erik


git-svn-id: svn://busybox.net/trunk/busybox@2233 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 5 insertions, 4 deletions

diff --git a/libbb/trim.c b/libbb/trim.c
index 8a9b07a14..be97d4924 100644
--- a/libbb/trim.c
+++ b/libbb/trim.c
@@ -33,13 +33,14 @@
 
 void trim(char *s)
 {
+        int len;
+
         /* trim trailing whitespace */
-        while (isspace(s[strlen(s)-1]))
-                s[strlen(s)-1]='\0';
+        while ( (len=strlen(s)) >= 1 && isspace(s[len-1]))
+                s[len-1]='\0';
 
         /* trim leading whitespace */
-        memmove(s, &s[strspn(s, " \n\r\t\v")], strlen(s));
-
+        memmove(s, &s[strspn(s, " \n\r\t\v")], len);
 }
 
 /* END CODE */