[PATCH] sparc: fix ldom_reboot buffer overflow harder

From: Kees Cook
Date: Wed Oct 02 2013 - 01:14:20 EST


The length argument to strlcpy was still wrong. It could overflow the end of
full_boot_str by 5 bytes. Instead of strcat and strlcpy, just use snprint.

Reported-by: Brad Spengler <spender@xxxxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
arch/sparc/kernel/ds.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/sparc/kernel/ds.c b/arch/sparc/kernel/ds.c
index 4d9ac84..dff60ab 100644
--- a/arch/sparc/kernel/ds.c
+++ b/arch/sparc/kernel/ds.c
@@ -849,9 +849,8 @@ void ldom_reboot(const char *boot_command)
if (boot_command && strlen(boot_command)) {
unsigned long len;

- strcpy(full_boot_str, "boot ");
- strlcpy(full_boot_str + strlen("boot "), boot_command,
- sizeof(full_boot_str));
+ snprintf(full_boot_str, sizeof(full_boot_str), "boot %s",
+ boot_command);
len = strlen(full_boot_str);

if (reboot_data_supported) {
--
1.7.9.5


--
Kees Cook
Chrome OS Security
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