diff options
| author | Jack Pham <jackp@codeaurora.org> | 2017-10-23 09:47:49 -0700 |
|---|---|---|
| committer | Jack Pham <jackp@codeaurora.org> | 2018-01-17 18:04:52 -0800 |
| commit | bc4f3590a73b0edd0c5ea3956adbe45e776f1206 (patch) | |
| tree | 8dd7c7686db56b520dba0a6764f058caca44d939 | |
| parent | 9f8d148622e4046522eded18f75f6ab363899f97 (diff) | |
usb: pd: avoid out-of-bounds access when reading PDOs
Most often a source will send fewer than the maximum number
of PDOs (7). Since the rx_msg buffer is now allocated up to
the size of the actual data, honor the rx_msg->data_len when
copying to pd->received_pdos rather than always 28 bytes.
This fixes out-of-bounds read access as reported by KASAN.
Change-Id: I5f98f7ccba027c1ab436ccf6fc822e2a319bafa1
Signed-off-by: Jack Pham <jackp@codeaurora.org>
| -rw-r--r-- | drivers/usb/pd/policy_engine.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/usb/pd/policy_engine.c b/drivers/usb/pd/policy_engine.c index 7225bfde8316..aef8de046b8e 100644 --- a/drivers/usb/pd/policy_engine.c +++ b/drivers/usb/pd/policy_engine.c @@ -2253,8 +2253,11 @@ static void usbpd_sm(struct work_struct *w) &val); /* save the PDOs so userspace can further evaluate */ - memcpy(&pd->received_pdos, rx_msg->payload, + memset(&pd->received_pdos, 0, sizeof(pd->received_pdos)); + memcpy(&pd->received_pdos, rx_msg->payload, + min_t(size_t, rx_msg->data_len, + sizeof(pd->received_pdos))); pd->src_cap_id++; usbpd_set_state(pd, PE_SNK_EVALUATE_CAPABILITY); @@ -2365,8 +2368,11 @@ static void usbpd_sm(struct work_struct *w) case PE_SNK_READY: if (IS_DATA(rx_msg, MSG_SOURCE_CAPABILITIES)) { /* save the PDOs so userspace can further evaluate */ - memcpy(&pd->received_pdos, rx_msg->payload, + memset(&pd->received_pdos, 0, sizeof(pd->received_pdos)); + memcpy(&pd->received_pdos, rx_msg->payload, + min_t(size_t, rx_msg->data_len, + sizeof(pd->received_pdos))); pd->src_cap_id++; usbpd_set_state(pd, PE_SNK_EVALUATE_CAPABILITY); |