mailbox: bcm-pdc: Use scnprintf() for avoiding potential buffer overflow

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
This commit is contained in:
Takashi Iwai 2020-03-11 08:45:13 +01:00 committed by Jassi Brar
parent 223a83bdcc
commit 38a5456a6d

View File

@ -436,33 +436,33 @@ static ssize_t pdc_debugfs_read(struct file *filp, char __user *ubuf,
pdcs = filp->private_data;
out_offset = 0;
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"SPU %u stats:\n", pdcs->pdc_idx);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"PDC requests....................%u\n",
pdcs->pdc_requests);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"PDC responses...................%u\n",
pdcs->pdc_replies);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"Tx not done.....................%u\n",
pdcs->last_tx_not_done);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"Tx ring full....................%u\n",
pdcs->tx_ring_full);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"Rx ring full....................%u\n",
pdcs->rx_ring_full);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"Tx desc write fail. Ring full...%u\n",
pdcs->txnobuf);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"Rx desc write fail. Ring full...%u\n",
pdcs->rxnobuf);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"Receive overflow................%u\n",
pdcs->rx_oflow);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
out_offset += scnprintf(buf + out_offset, out_count - out_offset,
"Num frags in rx ring............%u\n",
NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr,
pdcs->nrxpost));