From e3ae892e57245f3cac15e6e5e9d5b0d82bd4ab2c Mon Sep 17 00:00:00 2001 From: Seth Forshee Date: Mon, 14 Feb 2011 10:16:55 -0600 Subject: [PATCH] rt2x00: Check for errors from skb_pad() calls BugLink: http://bugs.launchpad.net/bugs/659143 Commit 739fd94 ("rt2x00: Pad beacon to multiple of 32 bits") added calls to skb_pad() without checking the return value, which could cause problems if any of those calls does happen to fail. Add checks to prevent this from happening. Signed-off-by: Seth Forshee --- drivers/net/wireless/rt2x00/rt2800pci.c | 11 +++++++++-- drivers/net/wireless/rt2x00/rt61pci.c | 11 +++++++++-- 2 files changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/rt2x00/rt2800pci.c b/drivers/net/wireless/rt2x00/rt2800pci.c index 9ad676d..e13666e 100644 --- a/drivers/net/wireless/rt2x00/rt2800pci.c +++ b/drivers/net/wireless/rt2x00/rt2800pci.c @@ -690,13 +690,14 @@ static void rt2800pci_write_beacon(struct queue_entry *entry, struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev; unsigned int beacon_base; unsigned int padding_len; - u32 reg; + u32 orig_reg, reg; /* * Disable beaconing while we are reloading the beacon data, * otherwise we might be sending out invalid data. */ rt2800_register_read(rt2x00dev, BCN_TIME_CFG, ®); + orig_reg = reg; rt2x00_set_field32(®, BCN_TIME_CFG_BEACON_GEN, 0); rt2800_register_write(rt2x00dev, BCN_TIME_CFG, reg); @@ -710,7 +711,13 @@ static void rt2800pci_write_beacon(struct queue_entry *entry, * Write entire beacon with TXWI and padding to register. */ padding_len = roundup(entry->skb->len, 4) - entry->skb->len; - skb_pad(entry->skb, padding_len); + if (padding_len && skb_pad(entry->skb, padding_len)) { + ERROR(rt2x00dev, "Failure padding beacon, aborting\n"); + /* skb freed by skb_pad() on failure */ + entry->skb = NULL; + rt2800_register_write(rt2x00dev, BCN_TIME_CFG, orig_reg); + return; + } beacon_base = HW_BEACON_OFFSET(entry->entry_idx); rt2800_register_multiwrite(rt2x00dev, beacon_base, entry->skb->data, entry->skb->len + padding_len); diff --git a/drivers/net/wireless/rt2x00/rt61pci.c b/drivers/net/wireless/rt2x00/rt61pci.c index 23bcb65..f4d1ec9 100644 --- a/drivers/net/wireless/rt2x00/rt61pci.c +++ b/drivers/net/wireless/rt2x00/rt61pci.c @@ -1864,13 +1864,14 @@ static void rt61pci_write_beacon(struct queue_entry *entry, struct queue_entry_priv_pci *entry_priv = entry->priv_data; unsigned int beacon_base; unsigned int padding_len; - u32 reg; + u32 orig_reg, reg; /* * Disable beaconing while we are reloading the beacon data, * otherwise we might be sending out invalid data. */ rt2x00pci_register_read(rt2x00dev, TXRX_CSR9, ®); + orig_reg = reg; rt2x00_set_field32(®, TXRX_CSR9_BEACON_GEN, 0); rt2x00pci_register_write(rt2x00dev, TXRX_CSR9, reg); @@ -1878,7 +1879,13 @@ static void rt61pci_write_beacon(struct queue_entry *entry, * Write entire beacon with descriptor and padding to register. */ padding_len = roundup(entry->skb->len, 4) - entry->skb->len; - skb_pad(entry->skb, padding_len); + if (padding_len && skb_pad(entry->skb, padding_len)) { + ERROR(rt2x00dev, "Failure padding beacon, aborting\n"); + /* skb freed by skb_pad() on failure */ + entry->skb = NULL; + rt2x00pci_register_write(rt2x00dev, TXRX_CSR9, orig_reg); + return; + } beacon_base = HW_BEACON_OFFSET(entry->entry_idx); rt2x00pci_register_multiwrite(rt2x00dev, beacon_base, entry_priv->desc, TXINFO_SIZE); -- 1.7.1