From: Alexander Aring Date: Mon, 27 Oct 2014 16:13:40 +0000 (+0100) Subject: ieee802154: add valid psdu length helper X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fa491001e4edae5ed68a562b61ed729968a3ca1c;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git ieee802154: add valid psdu length helper This patch adds a generic valid psdu length check function helper. This is useful to check the length field after receiving. For example the at86rf231 doesn't filter invalid psdu length. Sometimes the CRC can also be correct. If we get the lqi value with an invalid frame length the kernel may crash because we dereference an invalid pointer in the receive buffer. Signed-off-by: Alexander Aring Signed-off-by: Marcel Holtmann --- diff --git a/include/linux/ieee802154.h b/include/linux/ieee802154.h index 2dfab2db103a..6e50a2a1d485 100644 --- a/include/linux/ieee802154.h +++ b/include/linux/ieee802154.h @@ -23,7 +23,10 @@ #ifndef LINUX_IEEE802154_H #define LINUX_IEEE802154_H +#include + #define IEEE802154_MTU 127 +#define IEEE802154_MIN_PSDU_LEN 5 #define IEEE802154_FC_TYPE_BEACON 0x0 /* Frame is beacon */ #define IEEE802154_FC_TYPE_DATA 0x1 /* Frame is data */ @@ -185,5 +188,13 @@ enum { IEEE802154_SCAN_IN_PROGRESS = 0xfc, }; +/** + * ieee802154_is_valid_psdu_len - check if psdu len is valid + * @len: psdu len with (MHR + payload + MFR) + */ +static inline bool ieee802154_is_valid_psdu_len(const u8 len) +{ + return (len >= IEEE802154_MIN_PSDU_LEN && len <= IEEE802154_MTU); +} #endif /* LINUX_IEEE802154_H */