[PATCH] [2.6.2-rc3] Fix module.c pointer arithmetics

From: Carl-Daniel Hailfinger
Date: Sat Jan 31 2004 - 08:05:08 EST


Linus,
Rusty,

while studying the module code closely, I found a problem in
kernel/module.c:153ff.

for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++)

In combination with __start___ksymtab[i].name this will go eight times too
far. Proposed fix is attached.

Please apply before 2.6.2. If you think this makes the code too slow, I
can offer an alternative which will even speed up the current code.

Thanks,
Carl-Daniel
===== kernel/module.c 1.99 vs edited =====
--- 1.99/kernel/module.c Wed Jan 21 02:50:58 2004
+++ edited/kernel/module.c Sat Jan 31 13:50:47 2004
@@ -150,14 +150,14 @@

/* Core kernel first. */
*owner = NULL;
- for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++) {
+ for (i = 0; __start___ksymtab+i*sizeof(struct kernel_symbol) < __stop___ksymtab; i++) {
if (strcmp(__start___ksymtab[i].name, name) == 0) {
*crc = symversion(__start___kcrctab, i);
return __start___ksymtab[i].value;
}
}
if (gplok) {
- for (i = 0; __start___ksymtab_gpl+i<__stop___ksymtab_gpl; i++)
+ for (i = 0; __start___ksymtab_gpl+i*sizeof(struct kernel_symbol) < __stop___ksymtab_gpl; i++)
if (strcmp(__start___ksymtab_gpl[i].name, name) == 0) {
*crc = symversion(__start___kcrctab_gpl, i);
return __start___ksymtab_gpl[i].value;
@@ -1308,7 +1308,7 @@
unsigned int i;

if (!mod) {
- for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++)
+ for (i = 0; __start___ksymtab+i*sizeof(struct kernel_symbol) < __stop___ksymtab; i++)
if (strcmp(__start___ksymtab[i].name, name) == 0)
return 1;
return 0;