From 64dcbde7f8f870a4f2d9daf24ffb06f9748b5dd3 Mon Sep 17 00:00:00 2001 From: Junrui Luo Date: Sat, 14 Mar 2026 17:41:04 +0800 Subject: [PATCH] bnxt_en: fix OOB access in DBG_BUF_PRODUCER async event handler The ASYNC_EVENT_CMPL_EVENT_ID_DBG_BUF_PRODUCER handler in bnxt_async_event_process() uses a firmware-supplied 'type' field directly as an index into bp->bs_trace[] without bounds validation. The 'type' field is a 16-bit value extracted from DMA-mapped completion ring memory that the NIC writes directly to host RAM. A malicious or compromised NIC can supply any value from 0 to 65535, causing an out-of-bounds access into kernel heap memory. The bnxt_bs_trace_check_wrap() call then dereferences bs_trace->magic_byte and writes to bs_trace->last_offset and bs_trace->wrapped, leading to kernel memory corruption or a crash. Fix by adding a bounds check and defining BNXT_TRACE_MAX as DBG_LOG_BUFFER_FLUSH_REQ_TYPE_ERR_QPC_TRACE + 1 to cover all currently defined firmware trace types (0x0 through 0xc). Fixes: 84fcd9449fd7 ("bnxt_en: Manage the FW trace context memory") Reported-by: Yuhao Jiang Cc: stable@vger.kernel.org Signed-off-by: Junrui Luo Reviewed-by: Michael Chan Link: https://patch.msgid.link/SYBPR01MB7881A253A1C9775D277F30E9AF42A@SYBPR01MB7881.ausprd01.prod.outlook.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 ++ drivers/net/ethernet/broadcom/bnxt/bnxt.h | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index c426a41c3663..0751c0e4581a 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -2929,6 +2929,8 @@ static int bnxt_async_event_process(struct bnxt *bp, u16 type = (u16)BNXT_EVENT_BUF_PRODUCER_TYPE(data1); u32 offset = BNXT_EVENT_BUF_PRODUCER_OFFSET(data2); + if (type >= ARRAY_SIZE(bp->bs_trace)) + goto async_event_process_exit; bnxt_bs_trace_check_wrap(&bp->bs_trace[type], offset); goto async_event_process_exit; } diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h index 9a41b9e0423c..a97d651130df 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h @@ -2146,7 +2146,7 @@ enum board_idx { }; #define BNXT_TRACE_BUF_MAGIC_BYTE ((u8)0xbc) -#define BNXT_TRACE_MAX 11 +#define BNXT_TRACE_MAX (DBG_LOG_BUFFER_FLUSH_REQ_TYPE_ERR_QPC_TRACE + 1) struct bnxt_bs_trace_info { u8 *magic_byte;