From 7e57811ac5b595bdb53f2aef3bcb2b3d72663fa4 Mon Sep 17 00:00:00 2001 From: David Kilroy Date: Sat, 21 Feb 2009 16:52:53 +0000 Subject: orinoco: validate firmware header Check the Agere firmware headers for validity before attempting to download it. Signed-off-by: David Kilroy Signed-off-by: John W. Linville --- drivers/net/wireless/orinoco/fw.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'drivers/net/wireless/orinoco') diff --git a/drivers/net/wireless/orinoco/fw.c b/drivers/net/wireless/orinoco/fw.c index 7d2292d6ce09..9f163feb9362 100644 --- a/drivers/net/wireless/orinoco/fw.c +++ b/drivers/net/wireless/orinoco/fw.c @@ -43,6 +43,33 @@ struct orinoco_fw_header { char signature[0]; /* FW signature length headersize-20 */ } __attribute__ ((packed)); +/* Check the range of various header entries. Return a pointer to a + * description of the problem, or NULL if everything checks out. */ +static const char *validate_fw(const struct orinoco_fw_header *hdr, size_t len) +{ + u16 hdrsize; + + if (len < sizeof(*hdr)) + return "image too small"; + if (memcmp(hdr->hdr_vers, "HFW", 3) != 0) + return "format not recognised"; + + hdrsize = le16_to_cpu(hdr->headersize); + if (hdrsize > len) + return "bad headersize"; + if ((hdrsize + le32_to_cpu(hdr->block_offset)) > len) + return "bad block offset"; + if ((hdrsize + le32_to_cpu(hdr->pdr_offset)) > len) + return "bad PDR offset"; + if ((hdrsize + le32_to_cpu(hdr->pri_offset)) > len) + return "bad PRI offset"; + if ((hdrsize + le32_to_cpu(hdr->compat_offset)) > len) + return "bad compat offset"; + + /* TODO: consider adding a checksum or CRC to the firmware format */ + return NULL; +} + /* Download either STA or AP firmware into the card. */ static int orinoco_dl_firmware(struct orinoco_private *priv, @@ -58,6 +85,7 @@ orinoco_dl_firmware(struct orinoco_private *priv, const unsigned char *first_block; const unsigned char *end; const char *firmware; + const char *fw_err; struct net_device *dev = priv->ndev; int err = 0; @@ -93,6 +121,15 @@ orinoco_dl_firmware(struct orinoco_private *priv, hdr = (const struct orinoco_fw_header *) fw_entry->data; + fw_err = validate_fw(hdr, fw_entry->size); + if (fw_err) { + printk(KERN_WARNING "%s: Invalid firmware image detected (%s). " + "Aborting download\n", + dev->name, fw_err); + err = -EINVAL; + goto abort; + } + /* Enable aux port to allow programming */ err = hermesi_program_init(hw, le32_to_cpu(hdr->entry_point)); printk(KERN_DEBUG "%s: Program init returned %d\n", dev->name, err); -- cgit v1.2.1