In ca8210_skb_rx(), data_ind is read at offsets 22 (msdulen), 23 (mpdulinkquality), 29 + msdulen (hdr.sec.level), 30..39 + msdulen (security header), and 29 .. 29 + msdulen (payload) without verifying that the received SPI frame length len covers those offsets, causing an out-of-bounds read when msdulen exceeds len - 30: BUG: KASAN: slab-out-of-bounds in ca8210_skb_rx.constprop.0.isra.0+0x137/0x160 Read of size 64 at addr ffff888006453ddd by task init/1 Call Trace: dump_stack_lvl+0x70/0xa0 print_report+0x153/0x4c6 kasan_report+0xf1/0x120 kasan_check_range+0x125/0x200 __asan_memcpy+0x23/0x60 ca8210_skb_rx.constprop.0.isra.0+0x137/0x160 ca8210_net_rx+0x96/0xc0 ... The buggy address belongs to the object at ffff888006453dc0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 29 bytes inside of allocated 32-byte region [ffff888006453dc0, ffff888006453de0) Consolidate all length and msdulen validations into a single upfront check at the beginning of ca8210_skb_rx() before allocating the skb. Tested in QEMU with KASAN enabled by passing a short data_ind buffer with msdulen = 64 and len = 30 into ca8210_skb_rx(). Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver") Cc: stable@vger.kernel.org Assisted-by: LLM Signed-off-by: Hui Peng --- Changes in v3: - No changes. Changes in v2: - Split out as patch 3/3. - Consolidated all length checks in ca8210_skb_rx() into a single place at the beginning of the function before dev_alloc_skb() and dropped the unrelated hdr.seq assignment as requested by Miquel Raynal. drivers/net/ieee802154/ca8210.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-) diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c index 8aa7ffe..ab245ad 100644 --- a/drivers/net/ieee802154/ca8210.c +++ b/drivers/net/ieee802154/ca8210.c @@ -1758,19 +1758,15 @@ static int ca8210_skb_rx( u8 *data_ind ) { - struct ieee802154_hdr hdr; + struct ieee802154_hdr hdr = { }; int msdulen; int hlen; - u8 mpdulinkquality = data_ind[23]; + u8 mpdulinkquality; struct sk_buff *skb; struct ca8210_priv *priv = hw->priv; - /* Allocate mtu size buffer for every rx packet */ - skb = dev_alloc_skb(IEEE802154_MTU + sizeof(hdr)); - if (!skb) - return -ENOMEM; - - skb_reserve(skb, sizeof(hdr)); + if (len < 30) + return -EMSGSIZE; msdulen = data_ind[22]; /* msdu_length */ if (msdulen > IEEE802154_MTU) { @@ -1778,9 +1774,25 @@ static int ca8210_skb_rx( &priv->spi->dev, "received erroneously large msdu length!\n" ); - kfree_skb(skb); return -EMSGSIZE; } + + if (len < 30 + msdulen || + (!priv->promiscuous && data_ind[29 + msdulen] > 0 && + len < 29 + msdulen + sizeof(struct secspec))) { + dev_err(&priv->spi->dev, + "received truncated data indication!\n"); + return -EMSGSIZE; + } + + mpdulinkquality = data_ind[23]; + + /* Allocate mtu size buffer for every rx packet */ + skb = dev_alloc_skb(IEEE802154_MTU + sizeof(hdr)); + if (!skb) + return -ENOMEM; + + skb_reserve(skb, sizeof(hdr)); dev_dbg(&priv->spi->dev, "skb buffer length = %d\n", msdulen); if (priv->promiscuous) -- 2.49.0