Add sanity checks for both `tlv_len` and `tlv_bitmap_len` before decoding data from `event_buf`. This prevents any malicious or buggy firmware from overflowing `event_buf` through large values for `tlv_len` and `tlv_bitmap_len`. Suggested-by: Dan Williams <dcbw@xxxxxxxxxx> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> --- Changes in v2: - Fix format specifier: %ld -> %zu | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202308240844.leyoOwdG-lkp@xxxxxxxxx/ - Update warning messages to explicitly mention that TLV size is greater than tlv_buf_len. v1: - Link: https://lore.kernel.org/linux-hardening/587423b0737108effe82aefed4407daca39e9a51.1692829410.git.gustavoars@xxxxxxxxxx/ .../net/wireless/marvell/mwifiex/11n_rxreorder.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c index 735aac52bdc4..10690e82358b 100644 --- a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c +++ b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c @@ -921,6 +921,14 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private *priv, while (tlv_buf_left > sizeof(*tlv_rxba)) { tlv_type = le16_to_cpu(tlv_rxba->header.type); tlv_len = le16_to_cpu(tlv_rxba->header.len); + if (size_add(sizeof(tlv_rxba->header), tlv_len) > tlv_buf_left) { + mwifiex_dbg(priv->adapter, WARN, + "TLV size (%zu) overflows event_buf buf_left=%d\n", + size_add(sizeof(tlv_rxba->header), tlv_len), + tlv_buf_left); + return; + } + if (tlv_type != TLV_TYPE_RXBA_SYNC) { mwifiex_dbg(priv->adapter, ERROR, "Wrong TLV id=0x%x\n", tlv_type); @@ -929,6 +937,14 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private *priv, tlv_seq_num = le16_to_cpu(tlv_rxba->seq_num); tlv_bitmap_len = le16_to_cpu(tlv_rxba->bitmap_len); + if (size_add(sizeof(*tlv_rxba), tlv_bitmap_len) > tlv_buf_left) { + mwifiex_dbg(priv->adapter, WARN, + "TLV size (%zu) overflows event_buf buf_left=%d\n", + size_add(sizeof(*tlv_rxba), tlv_bitmap_len), + tlv_buf_left); + return; + } + mwifiex_dbg(priv->adapter, INFO, "%pM tid=%d seq_num=%d bitmap_len=%d\n", tlv_rxba->mac, tlv_rxba->tid, tlv_seq_num, -- 2.34.1
