From af31cb5a57084146aae5c01df6b85f54067528aa Mon Sep 17 00:00:00 2001 From: Vladimir Kondratiev Date: Sun, 2 Mar 2014 11:20:50 +0200 Subject: [PATCH] wil6210: fix buffer overflow in wil_txdesc_debugfs_show() Wrong index comparison logic, found by smatch: drivers/net/wireless/ath/wil6210/debugfs.c:402 wil_txdesc_debugfs_show() warn: buffer overflow 'wil->vring_tx' 24 <= 24 Signed-off-by: Vladimir Kondratiev Signed-off-by: John W. Linville --- drivers/net/wireless/ath/wil6210/debugfs.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/ath/wil6210/debugfs.c b/drivers/net/wireless/ath/wil6210/debugfs.c index 729e774..1d09a4b 100644 --- a/drivers/net/wireless/ath/wil6210/debugfs.c +++ b/drivers/net/wireless/ath/wil6210/debugfs.c @@ -26,8 +26,7 @@ /* Nasty hack. Better have per device instances */ static u32 mem_addr; static u32 dbg_txdesc_index; -static u32 dbg_vring_index; /* 25 for Rx, 0..24 for Tx */ -#define WIL_DBG_VRING_INDEX_RX (WIL6210_MAX_TX_RINGS + 1) +static u32 dbg_vring_index; /* 24+ for Rx, 0..23 for Tx */ static void wil_print_vring(struct seq_file *s, struct wil6210_priv *wil, const char *name, struct vring *vring, @@ -404,13 +403,14 @@ static int wil_txdesc_debugfs_show(struct seq_file *s, void *data) { struct wil6210_priv *wil = s->private; struct vring *vring; - if (dbg_vring_index <= WIL6210_MAX_TX_RINGS) + bool tx = (dbg_vring_index < WIL6210_MAX_TX_RINGS); + if (tx) vring = &(wil->vring_tx[dbg_vring_index]); else vring = &wil->vring_rx; if (!vring->va) { - if (dbg_vring_index <= WIL6210_MAX_TX_RINGS) + if (tx) seq_printf(s, "No Tx[%2d] VRING\n", dbg_vring_index); else seq_puts(s, "No Rx VRING\n"); @@ -426,7 +426,7 @@ static int wil_txdesc_debugfs_show(struct seq_file *s, void *data) volatile u32 *u = (volatile u32 *)d; struct sk_buff *skb = vring->ctx[dbg_txdesc_index].skb; - if (dbg_vring_index <= WIL6210_MAX_TX_RINGS) + if (tx) seq_printf(s, "Tx[%2d][%3d] = {\n", dbg_vring_index, dbg_txdesc_index); else @@ -461,7 +461,7 @@ static int wil_txdesc_debugfs_show(struct seq_file *s, void *data) } seq_printf(s, "}\n"); } else { - if (dbg_vring_index <= WIL6210_MAX_TX_RINGS) + if (tx) seq_printf(s, "[%2d] TxDesc index (%d) >= size (%d)\n", dbg_vring_index, dbg_txdesc_index, vring->size); -- 2.7.4