[PATCH] x86: Buffer overflow

[PATCH] x86: Buffer overflow

[Roel Kluin]

If the vendor name (from c16) can be longer than 100 bytes (or missing a
terminating null), then the null is writen past the end of vendor[].

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
---
Found with Parfait, http://research.sun.com/projects/parfait/

diff --git a/arch/x86/kernel/efi.c b/arch/x86/kernel/efi.c
index 96f7ac0..436a42f 100644
--- a/arch/x86/kernel/efi.c
+++ b/arch/x86/kernel/efi.c
@@ -354,7 +354,7 @@ void __init efi_init(void)
 	 */
 	c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 	if (c16) {
-		for (i = 0; i < sizeof(vendor) && *c16; ++i)
+		for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 			vendor[i] = *c16++;
 		vendor[i] = '\0';
 	} else