In ca8210_spi_transfer(), each SPI transfer reads sizeof(struct mac_message) bytes into cas_ctl->tx_in_buf: cas_ctl->transfer.len = sizeof(struct mac_message); However, ca8210_rx_done() only checks the received packet length len = buf[1] + 2 against CA8210_SPI_BUF_SIZE (256). When buf[0] & SPI_SYN is set and priv->sync_command_response is non-NULL, memcpy() copies up to 256 bytes into priv->sync_command_response, which points to a struct mac_message object on the synchronous caller's stack, overflowing the stack buffer: BUG: KASAN: stack-out-of-bounds in ca8210_rx_done+0x117/0x6c0 Write of size 256 at addr ffff8881009e7c40 by task swapper/0/1 Call Trace: dump_stack_lvl+0x70/0xa0 print_report+0x153/0x4c6 kasan_report+0xf1/0x120 kasan_check_range+0x125/0x200 __asan_memcpy+0x3c/0x60 ca8210_rx_done+0x117/0x6c0 ... This frame has 1 object: [32, 182) 'response' Check len > sizeof(struct mac_message) instead of len > CA8210_SPI_BUF_SIZE in ca8210_rx_done() so that any packet exceeding sizeof(struct mac_message) is logged as erroneously long via dev_crit() and dropped before copying into priv->sync_command_response or passing it to ca8210_net_rx(). Tested in QEMU with KASAN enabled by passing a 256-byte SPI_SYN response into ca8210_rx_done(). 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: - Check len > sizeof(struct mac_message) at the top of ca8210_rx_done() where dev_crit() logs the error and drops the packet instead of silently truncating memcpy() with min_t(), addressing David Laight's feedback. Changes in v2: - Split the ca8210 fixes into three single-issue patches (1/3..3/3). drivers/net/ieee802154/ca8210.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c index 01af4f9..a990a0f 100644 --- a/drivers/net/ieee802154/ca8210.c +++ b/drivers/net/ieee802154/ca8210.c @@ -686,7 +686,7 @@ static void ca8210_rx_done(struct cas_control *cas_ctl) buf = cas_ctl->tx_in_buf; len = buf[1] + 2; - if (len > CA8210_SPI_BUF_SIZE) { + if (len > sizeof(struct mac_message)) { dev_crit( &priv->spi->dev, "Received packet len (%u) erroneously long\n", -- 2.49.0 In ca8210_get_ed(), an uninitialized u8 lenvar and a pointer to a 1-byte stack buffer (u8 *level) are passed to hwme_get_request_sync(), which unconditionally copies response.pdata.hwme_get_cnf.hw_attribute_length bytes into hw_attribute_value without checking the caller's destination buffer capacity, overflowing level on the stack when hw_attribute_length exceeds 1: BUG: KASAN: stack-out-of-bounds in hwme_get_request_sync.constprop.0.isra.0+0xf3/0x170 Write of size 16 at addr ffff888001907780 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+0x3c/0x60 hwme_get_request_sync.constprop.0.isra.0+0xf3/0x170 ca8210_get_ed+0x9c/0xf0 ... The buggy address belongs to stack of task init/1 and is located at offset 48 in frame: ca8210_get_ed+0x0/0xf0 This frame has 2 objects: [48, 49) 'level' [64, 65) 'lenvar' Initialize lenvar = 1 in ca8210_get_ed() and return IEEE802154_SYSTEM_ERROR in hwme_get_request_sync() if response.pdata.hwme_get_cnf.hw_attribute_length exceeds *hw_attribute_length. Tested in QEMU with KASAN enabled by passing an oversized hw_attribute_length response into ca8210_get_ed(). 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 2/3. - Replaced the temporary stack buffer in ca8210_get_ed() with lenvar = 1 and an upper-bound check against *hw_attribute_length in hwme_get_request_sync() as requested by Miquel Raynal. drivers/net/ieee802154/ca8210.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c index a990a0f..8aa7ffe 100644 --- a/drivers/net/ieee802154/ca8210.c +++ b/drivers/net/ieee802154/ca8210.c @@ -1677,6 +1677,9 @@ static u8 hwme_get_request_sync( return IEEE802154_SYSTEM_ERROR; if (response.pdata.hwme_get_cnf.status == IEEE802154_SUCCESS) { + if (response.pdata.hwme_get_cnf.hw_attribute_length > + *hw_attribute_length) + return IEEE802154_SYSTEM_ERROR; *hw_attribute_length = response.pdata.hwme_get_cnf.hw_attribute_length; memcpy( @@ -2027,7 +2030,7 @@ static int ca8210_xmit_async(struct ieee802154_hw *hw, struct sk_buff *skb) */ static int ca8210_get_ed(struct ieee802154_hw *hw, u8 *level) { - u8 lenvar; + u8 lenvar = 1; struct ca8210_priv *priv = hw->priv; return link_to_linux_err( -- 2.49.0 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