Messages in this thread Patch in this message | | | Date | Mon, 23 Mar 2015 05:23:32 -0700 | From | tip-bot for Arjun Sreedharan <> | Subject | [tip:x86/boot] x86/boot: Standardize strcmp() |
| |
Commit-ID: 1c1d046be692493d00a4831d4fbc266745008e09 Gitweb: http://git.kernel.org/tip/1c1d046be692493d00a4831d4fbc266745008e09 Author: Arjun Sreedharan <arjun024@gmail.com> AuthorDate: Mon, 16 Mar 2015 21:07:47 +0530 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Mon, 23 Mar 2015 10:24:12 +0100
x86/boot: Standardize strcmp()
strcmp() is always expected to return 0 when arguments are equal, negative when its first argument @str1 is less than its second argument @str2 and a positive value otherwise. Previously strcmp("a", "b") returned 1. Now it gives -1, as it is supposed to.
Until now this bug never triggered, because all uses for strcmp() in the boot code tested for nonzero:
triton:~/tip> git grep strcmp arch/x86/boot/ arch/x86/boot/boot.h:int strcmp(const char *str1, const char *str2); arch/x86/boot/edd.c: if (!strcmp(eddarg, "skipmbr") || !strcmp(eddarg, "skip")) { arch/x86/boot/edd.c: else if (!strcmp(eddarg, "off")) arch/x86/boot/edd.c: else if (!strcmp(eddarg, "on"))
should in the future strcmp() be used in a comparative way in the boot code, it might have led to (not so subtle) bugs.
Signed-off-by: Arjun Sreedharan <arjun024@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426520267-1803-1-git-send-email-arjun024@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/x86/boot/string.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c index 493f3fd..318b846 100644 --- a/arch/x86/boot/string.c +++ b/arch/x86/boot/string.c @@ -30,7 +30,7 @@ int strcmp(const char *str1, const char *str2) int delta = 0; while (*s1 || *s2) { - delta = *s2 - *s1; + delta = *s1 - *s2; if (delta) return delta; s1++;
| |