From: Dave Hansen <[email protected]> __cmdline_find_option_bool() tries to account for both NULL-terminated and non-NULL-terminated strings. It keeps 'pos' to look for the end of the buffer and also looks for '!c' in a bunch of places to look for NULL termination.
But, it also calls strlen(). You can't call strlen on a non-NULL-terminated string. If !strlen(cmdline), then cmdline[0]=='\0'. In that case, we will go in to the while() loop, set c='\0', hit st_wordstart, notice !c, and will immediately return 0. So, remove the strlen(). It is unnecessary and unsafe. Signed-off-by: Dave Hansen <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] --- b/arch/x86/lib/cmdline.c | 3 --- 1 file changed, 3 deletions(-) diff -puN arch/x86/lib/cmdline.c~x86-early-command-line-non-term arch/x86/lib/cmdline.c --- a/arch/x86/lib/cmdline.c~x86-early-command-line-non-term 2015-12-17 13:54:54.211004070 -0800 +++ b/arch/x86/lib/cmdline.c 2015-12-17 13:54:54.214004206 -0800 @@ -41,9 +41,6 @@ static int __cmdline_find_option_bool(co if (!cmdline) return -1; /* No command line */ - if (!strlen(cmdline)) - return 0; - /* * This 'pos' check ensures we do not overrun * a non-NULL-terminated 'cmdline' _ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
