From b42190c04b9e530fbe92c2fa200e0eae2cc83224 Mon Sep 17 00:00:00 2001 From: John Haxby Date: Wed, 9 Jun 2010 16:36:28 +0100 Subject: [PATCH] xt_SYSRQ: fix a couple of problems The first problem is that the error response from crypto_alloc_hash() should be extracted from the pointer before setting the pointer to NULL. The second error is that only the first half of the password hash is checked which slightly weakens the password checking. Signed-off-by: John Haxby --- extensions/xt_SYSRQ.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/extensions/xt_SYSRQ.c b/extensions/xt_SYSRQ.c index e0b6aa0..a013051 100644 --- a/extensions/xt_SYSRQ.c +++ b/extensions/xt_SYSRQ.c @@ -135,13 +135,13 @@ static unsigned int sysrq_tg(const void *pdata, uint16_t len) "0123456789abcdef"[sysrq_digest[i] & 0xf]; } sysrq_hexdigest[2*sysrq_digest_size] = '\0'; - if (len - n < sysrq_digest_size) { + if (len - n < sysrq_digest_size * 2) { if (sysrq_debug) printk(KERN_INFO KBUILD_MODNAME ": Short digest," " expected %s\n", sysrq_hexdigest); return NF_DROP; } - if (strncmp(data + n, sysrq_hexdigest, sysrq_digest_size) != 0) { + if (strncmp(data + n, sysrq_hexdigest, sysrq_digest_size * 2) != 0) { if (sysrq_debug) printk(KERN_INFO KBUILD_MODNAME ": Bad digest," " expected %s\n", sysrq_hexdigest); @@ -324,8 +324,8 @@ static int __init sysrq_crypto_init(void) printk(KERN_WARNING KBUILD_MODNAME ": Error: Could not find or load %s hash\n", sysrq_hash); - sysrq_tfm = NULL; ret = PTR_ERR(sysrq_tfm); + sysrq_tfm = NULL; goto fail; } sysrq_digest_size = crypto_hash_digestsize(sysrq_tfm);