From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konstantin Sharlaimov Date: Fri, 01 Jun 2007 10:31:48 +0000 Subject: [PATCH 2.6.21.3] ppp_mppe: account for osize too small errors in Message-Id: <465FF594.50901@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ppp@vger.kernel.org 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 there errors from occurring. Signed-off-by: Konstantin Sharlaimov --- --- linux-2.6.21.3/drivers/net/ppp_mppe.c.orig 2007-06-01 20:57:04.000000000 +1100 +++ linux-2.6.21.3/drivers/net/ppp_mppe.c 2007-06-01 21:08:03.000000000 +1100 @@ -493,14 +493,14 @@ mppe_decompress(void *arg, unsigned char /* * 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 */