Commit-ID: 4de07ea481361b08fe13735004dafae862482d38 Gitweb: http://git.kernel.org/tip/4de07ea481361b08fe13735004dafae862482d38 Author: Dave Hansen <[email protected]> AuthorDate: Tue, 22 Dec 2015 14:52:41 -0800 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 3 Feb 2016 12:03:17 +0100
x86/boot: Simplify early command line parsing __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]> Signed-off-by: Borislav Petkov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/lib/cmdline.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/arch/x86/lib/cmdline.c b/arch/x86/lib/cmdline.c index ff8d1be..945a639 100644 --- a/arch/x86/lib/cmdline.c +++ b/arch/x86/lib/cmdline.c @@ -39,9 +39,6 @@ int cmdline_find_option_bool(const char *cmdline, const char *option) 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'
