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| author | David Herrmann <dh.herrmann@gmail.com> | 2013-12-19 12:09:32 +0100 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2014-02-17 21:17:55 +0100 |
| commit | a4b1b5877b514b276f0f31efe02388a9c2836728 (patch) | |
| tree | a09dd741c0a2b98db2ab8f71b45c5dc92efcc02c /net | |
| parent | 218eb9ed840c6279686ed6b0c3e31a083e241ff9 (diff) | |
| download | linux-a4b1b5877b514b276f0f31efe02388a9c2836728.tar.gz | |
HID: Bluetooth: hidp: make sure input buffers are big enough
HID core expects the input buffers to be at least of size 4096 (HID_MAX_BUFFER_SIZE). Other sizes will result in buffer-overflows if an input-report is smaller than advertised. We could, like i2c, compute the biggest report-size instead of using HID_MAX_BUFFER_SIZE, but this will blow up if report-descriptors are changed after ->start() has been called. So lets be safe and just use the biggest buffer we have. Note that this adds an additional copy to the HIDP input path. If there is a way to make sure the skb-buf is big enough, we should use that instead. The best way would be to make hid-core honor the @size argument, though, that sounds easier than it is. So lets just fix the buffer-overflows for now and afterwards look for a faster way for all transport drivers. Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'net')
| -rw-r--r-- | net/bluetooth/hidp/core.c | 16 | ||||
| -rw-r--r-- | net/bluetooth/hidp/hidp.h | 4 |
2 files changed, 18 insertions, 2 deletions
diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c index 292e619db896..d9fb93451442 100644 --- a/net/bluetooth/hidp/core.c +++ b/net/bluetooth/hidp/core.c @@ -430,6 +430,16 @@ static void hidp_del_timer(struct hidp_session *session) del_timer(&session->timer); } +static void hidp_process_report(struct hidp_session *session, + int type, const u8 *data, int len, int intr) +{ + if (len > HID_MAX_BUFFER_SIZE) + len = HID_MAX_BUFFER_SIZE; + + memcpy(session->input_buf, data, len); + hid_input_report(session->hid, type, session->input_buf, len, intr); +} + static void hidp_process_handshake(struct hidp_session *session, unsigned char param) { @@ -502,7 +512,8 @@ static int hidp_process_data(struct hidp_session *session, struct sk_buff *skb, hidp_input_report(session, skb); if (session->hid) - hid_input_report(session->hid, HID_INPUT_REPORT, skb->data, skb->len, 0); + hidp_process_report(session, HID_INPUT_REPORT, + skb->data, skb->len, 0); break; case HIDP_DATA_RTYPE_OTHER: @@ -584,7 +595,8 @@ static void hidp_recv_intr_frame(struct hidp_session *session, hidp_input_report(session, skb); if (session->hid) { - hid_input_report(session->hid, HID_INPUT_REPORT, skb->data, skb->len, 1); + hidp_process_report(session, HID_INPUT_REPORT, + skb->data, skb->len, 1); BT_DBG("report len %d", skb->len); } } else { diff --git a/net/bluetooth/hidp/hidp.h b/net/bluetooth/hidp/hidp.h index ab5241400cf7..8798492a6e99 100644 --- a/net/bluetooth/hidp/hidp.h +++ b/net/bluetooth/hidp/hidp.h @@ -24,6 +24,7 @@ #define __HIDP_H #include <linux/types.h> +#include <linux/hid.h> #include <linux/kref.h> #include <net/bluetooth/bluetooth.h> #include <net/bluetooth/l2cap.h> @@ -179,6 +180,9 @@ struct hidp_session { /* Used in hidp_output_raw_report() */ int output_report_success; /* boolean */ + + /* temporary input buffer */ + u8 input_buf[HID_MAX_BUFFER_SIZE]; }; /* HIDP init defines */ |