Le 30/04/2021 à 06:22, Daniel Walker a écrit :
This systems allows some string functions to be moved into
lib/early_string.c and they will be prepended with "early_" and compiled
without debugging like KASAN.
This is already done on x86 for,
"AMD Secure Memory Encryption (SME) support"
and on powerpc prom_init.c , and EFI's libstub.
The AMD memory feature disabled KASAN for all string functions, and
prom_init.c and efi libstub implement their own versions of the
functions.
This implementation allows sharing of the string functions without
removing the debugging features for the whole system.
This looks good. I prefer that rather than the way you proposed to do it two
years ago.
Only one problem, see below.
+size_t strlcat(char *dest, const char *src, size_t count)
+{
+ size_t dsize = strlen(dest);
+ size_t len = strlen(src);
+ size_t res = dsize + len;
+
+ /* This would be a bug */
+ BUG_ON(dsize >= count);
powerpc is not ready to handle BUG_ON() in when in prom_init.
Can you do:
#ifndef __EARLY_STRING_ENABLED
BUG_ON(dsize >= count);
#endif
+
+ dest += dsize;
+ count -= dsize;
+ if (len >= count)
+ len = count-1;
+ memcpy(dest, src, len);
+ dest[len] = 0;
+ return res;
+}
+EXPORT_SYMBOL(strlcat);
+#endif
+
