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authorLinus Torvalds <torvalds@linux-foundation.org>2016-11-05 11:17:34 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-11-05 11:17:34 -0700
commit03daa36f089f31002a2d0fb22088d3ebe3e28d98 (patch)
treeaca2f62c3deab0a5fbaa807fc9ce71c9efa1dd5c
parentd8d1721cfb3162abbda078d67a928792d6552b84 (diff)
parente9300a4b7bbae83af1f7703938c94cf6dc6d308f (diff)
Merge tag 'firewire-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394
Pull FireWire (IEEE 1394) fixes from Stefan Richter: - add missing input validation to the firewire-net driver. Invalid IP-over-1394 encapsulation headers could trigger buffer overflows (CVE 2016-8633). - IP-over-1394 link fragmentation headers were read and written incorrectly, breaking fragmented RX/TX with other OS's stacks. * tag 'firewire-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394: firewire: net: fix fragmented datagram_size off-by-one firewire: net: guard against rx buffer overflows
-rw-r--r--drivers/firewire/net.c59
1 files changed, 39 insertions, 20 deletions
diff --git a/drivers/firewire/net.c b/drivers/firewire/net.c
index 309311b1faae..15475892af0c 100644
--- a/drivers/firewire/net.c
+++ b/drivers/firewire/net.c
@@ -73,13 +73,13 @@ struct rfc2734_header {
#define fwnet_get_hdr_lf(h) (((h)->w0 & 0xc0000000) >> 30)
#define fwnet_get_hdr_ether_type(h) (((h)->w0 & 0x0000ffff))
-#define fwnet_get_hdr_dg_size(h) (((h)->w0 & 0x0fff0000) >> 16)
+#define fwnet_get_hdr_dg_size(h) ((((h)->w0 & 0x0fff0000) >> 16) + 1)
#define fwnet_get_hdr_fg_off(h) (((h)->w0 & 0x00000fff))
#define fwnet_get_hdr_dgl(h) (((h)->w1 & 0xffff0000) >> 16)
-#define fwnet_set_hdr_lf(lf) ((lf) << 30)
+#define fwnet_set_hdr_lf(lf) ((lf) << 30)
#define fwnet_set_hdr_ether_type(et) (et)
-#define fwnet_set_hdr_dg_size(dgs) ((dgs) << 16)
+#define fwnet_set_hdr_dg_size(dgs) (((dgs) - 1) << 16)
#define fwnet_set_hdr_fg_off(fgo) (fgo)
#define fwnet_set_hdr_dgl(dgl) ((dgl) << 16)
@@ -578,6 +578,9 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
int retval;
u16 ether_type;
+ if (len <= RFC2374_UNFRAG_HDR_SIZE)
+ return 0;
+
hdr.w0 = be32_to_cpu(buf[0]);
lf = fwnet_get_hdr_lf(&hdr);
if (lf == RFC2374_HDR_UNFRAG) {
@@ -602,7 +605,12 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
return fwnet_finish_incoming_packet(net, skb, source_node_id,
is_broadcast, ether_type);
}
+
/* A datagram fragment has been received, now the fun begins. */
+
+ if (len <= RFC2374_FRAG_HDR_SIZE)
+ return 0;
+
hdr.w1 = ntohl(buf[1]);
buf += 2;
len -= RFC2374_FRAG_HDR_SIZE;
@@ -614,7 +622,10 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
fg_off = fwnet_get_hdr_fg_off(&hdr);
}
datagram_label = fwnet_get_hdr_dgl(&hdr);
- dg_size = fwnet_get_hdr_dg_size(&hdr); /* ??? + 1 */
+ dg_size = fwnet_get_hdr_dg_size(&hdr);
+
+ if (fg_off + len > dg_size)
+ return 0;
spin_lock_irqsave(&dev->lock, flags);
@@ -722,6 +733,22 @@ static void fwnet_receive_packet(struct fw_card *card, struct fw_request *r,
fw_send_response(card, r, rcode);
}
+static int gasp_source_id(__be32 *p)
+{
+ return be32_to_cpu(p[0]) >> 16;
+}
+
+static u32 gasp_specifier_id(__be32 *p)
+{
+ return (be32_to_cpu(p[0]) & 0xffff) << 8 |
+ (be32_to_cpu(p[1]) & 0xff000000) >> 24;
+}
+
+static u32 gasp_version(__be32 *p)
+{
+ return be32_to_cpu(p[1]) & 0xffffff;
+}
+
static void fwnet_receive_broadcast(struct fw_iso_context *context,
u32 cycle, size_t header_length, void *header, void *data)
{
@@ -731,9 +758,6 @@ static void fwnet_receive_broadcast(struct fw_iso_context *context,
__be32 *buf_ptr;
int retval;
u32 length;
- u16 source_node_id;
- u32 specifier_id;
- u32 ver;
unsigned long offset;
unsigned long flags;
@@ -750,22 +774,17 @@ static void fwnet_receive_broadcast(struct fw_iso_context *context,
spin_unlock_irqrestore(&dev->lock, flags);
- specifier_id = (be32_to_cpu(buf_ptr[0]) & 0xffff) << 8
- | (be32_to_cpu(buf_ptr[1]) & 0xff000000) >> 24;
- ver = be32_to_cpu(buf_ptr[1]) & 0xffffff;
- source_node_id = be32_to_cpu(buf_ptr[0]) >> 16;
-
- if (specifier_id == IANA_SPECIFIER_ID &&
- (ver == RFC2734_SW_VERSION
+ if (length > IEEE1394_GASP_HDR_SIZE &&
+ gasp_specifier_id(buf_ptr) == IANA_SPECIFIER_ID &&
+ (gasp_version(buf_ptr) == RFC2734_SW_VERSION
#if IS_ENABLED(CONFIG_IPV6)
- || ver == RFC3146_SW_VERSION
+ || gasp_version(buf_ptr) == RFC3146_SW_VERSION
#endif
- )) {
- buf_ptr += 2;
- length -= IEEE1394_GASP_HDR_SIZE;
- fwnet_incoming_packet(dev, buf_ptr, length, source_node_id,
+ ))
+ fwnet_incoming_packet(dev, buf_ptr + 2,
+ length - IEEE1394_GASP_HDR_SIZE,
+ gasp_source_id(buf_ptr),
context->card->generation, true);
- }
packet.payload_length = dev->rcv_buffer_size;
packet.interrupt = 1;