From: Konstantin Sharlaimov Date: Tue, 12 Jun 2007 21:16:59 +0000 (-0700) Subject: [PPP_MPPE]: Fix "osize too small" check. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=606f585e363527da9feaed79465132c0c661fd9e;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git [PPP_MPPE]: Fix "osize too small" check. Prevent mppe_decompress() from generating "osize too small" errors when checking for output buffer size. When receiving a packet of mru size the output buffer for decrypted data is 1 byte too small since mppe_decompress() tries to account for possible PFC, however later in code it is assumed no PFC. Adjusting the check prevented these errors from occurring. Signed-off-by: Konstantin Sharlaimov Signed-off-by: Andrew Morton Signed-off-by: David S. Miller --- diff --git a/drivers/net/ppp_mppe.c b/drivers/net/ppp_mppe.c index d5bdd257465..5ae80bbe2ed 100644 --- a/drivers/net/ppp_mppe.c +++ b/drivers/net/ppp_mppe.c @@ -493,14 +493,14 @@ mppe_decompress(void *arg, unsigned char *ibuf, int isize, unsigned char *obuf, /* * Make sure we have enough room to decrypt the packet. - * Note that for our test we only subtract 1 byte whereas in - * mppe_compress() we added 2 bytes (+MPPE_OVHD); - * this is to account for possible PFC. + * To account for possible PFC we should only subtract 1 + * byte whereas in mppe_compress() we added 2 bytes (+MPPE_OVHD); + * However, we assume no PFC, thus subtracting 2 bytes. */ - if (osize < isize - MPPE_OVHD - 1) { + if (osize < isize - MPPE_OVHD - 2) { printk(KERN_DEBUG "mppe_decompress[%d]: osize too small! " "(have: %d need: %d)\n", state->unit, - osize, isize - MPPE_OVHD - 1); + osize, isize - MPPE_OVHD - 2); return DECOMP_ERROR; } osize = isize - MPPE_OVHD - 2; /* assume no PFC */