Commit 7e4a6da7 authored by David S. Miller's avatar David S. Miller
Browse files

[PPP]: Revert 606f585e 



This can cause packet buffer overflows in certain cases,
the real bug will be fixed differently in a followon
changeset.

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 64beb8f3

drivers/net/ppp_mppe.c

+5 −5
Original line number Diff line number Diff line
@@ -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.

	 * 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.

	 * 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.

	 */

	if (osize < isize - MPPE_OVHD - 2) {

	if (osize < isize - MPPE_OVHD - 1) {

		printk(KERN_DEBUG "mppe_decompress[%d]: osize too small! "

		       "(have: %d need: %d)\n", state->unit,

		       osize, isize - MPPE_OVHD - 2);

		       osize, isize - MPPE_OVHD - 1);

		return DECOMP_ERROR;

	}

	osize = isize - MPPE_OVHD - 2;	/* assume no PFC */