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| author | Takashi Iwai <tiwai@suse.de> | 2020-03-15 10:35:02 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-03-15 17:06:22 -0700 |
| commit | 5e892880e14fbc1944f49aa42a67496516fe5dac (patch) | |
| tree | 2ce9e7d22d7eadde22060ef8a03beaa8bffbe049 /drivers/net/ethernet/sfc/mcdi.c | |
| parent | 38e0f746c456b2f7d64b37aef3b6bd9ad73508c0 (diff) | |
| download | lwn-5e892880e14fbc1944f49aa42a67496516fe5dac.tar.gz lwn-5e892880e14fbc1944f49aa42a67496516fe5dac.zip | |
net: sfc: 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().
Cc: "David S . Miller" <davem@davemloft.net>
Cc: Edward Cree <ecree@solarflare.com>
Cc: Martin Habets <mhabets@solarflare.com>
Cc: Solarflare linux maintainers <linux-net-drivers@solarflare.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/sfc/mcdi.c')
| -rw-r--r-- | drivers/net/ethernet/sfc/mcdi.c | 32 |
1 files changed, 18 insertions, 14 deletions
diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c index 2713300343c7..15c731d04065 100644 --- a/drivers/net/ethernet/sfc/mcdi.c +++ b/drivers/net/ethernet/sfc/mcdi.c @@ -212,12 +212,14 @@ static void efx_mcdi_send_request(struct efx_nic *efx, unsigned cmd, * progress on a NIC at any one time. So no need for locking. */ for (i = 0; i < hdr_len / 4 && bytes < PAGE_SIZE; i++) - bytes += snprintf(buf + bytes, PAGE_SIZE - bytes, - " %08x", le32_to_cpu(hdr[i].u32[0])); + bytes += scnprintf(buf + bytes, PAGE_SIZE - bytes, + " %08x", + le32_to_cpu(hdr[i].u32[0])); for (i = 0; i < inlen / 4 && bytes < PAGE_SIZE; i++) - bytes += snprintf(buf + bytes, PAGE_SIZE - bytes, - " %08x", le32_to_cpu(inbuf[i].u32[0])); + bytes += scnprintf(buf + bytes, PAGE_SIZE - bytes, + " %08x", + le32_to_cpu(inbuf[i].u32[0])); netif_info(efx, hw, efx->net_dev, "MCDI RPC REQ:%s\n", buf); } @@ -302,15 +304,15 @@ static void efx_mcdi_read_response_header(struct efx_nic *efx) */ for (i = 0; i < hdr_len && bytes < PAGE_SIZE; i++) { efx->type->mcdi_read_response(efx, &hdr, (i * 4), 4); - bytes += snprintf(buf + bytes, PAGE_SIZE - bytes, - " %08x", le32_to_cpu(hdr.u32[0])); + bytes += scnprintf(buf + bytes, PAGE_SIZE - bytes, + " %08x", le32_to_cpu(hdr.u32[0])); } for (i = 0; i < data_len && bytes < PAGE_SIZE; i++) { efx->type->mcdi_read_response(efx, &hdr, mcdi->resp_hdr_len + (i * 4), 4); - bytes += snprintf(buf + bytes, PAGE_SIZE - bytes, - " %08x", le32_to_cpu(hdr.u32[0])); + bytes += scnprintf(buf + bytes, PAGE_SIZE - bytes, + " %08x", le32_to_cpu(hdr.u32[0])); } netif_info(efx, hw, efx->net_dev, "MCDI RPC RESP:%s\n", buf); @@ -1417,9 +1419,11 @@ void efx_mcdi_print_fwver(struct efx_nic *efx, char *buf, size_t len) } ver_words = (__le16 *)MCDI_PTR(outbuf, GET_VERSION_OUT_VERSION); - offset = snprintf(buf, len, "%u.%u.%u.%u", - le16_to_cpu(ver_words[0]), le16_to_cpu(ver_words[1]), - le16_to_cpu(ver_words[2]), le16_to_cpu(ver_words[3])); + offset = scnprintf(buf, len, "%u.%u.%u.%u", + le16_to_cpu(ver_words[0]), + le16_to_cpu(ver_words[1]), + le16_to_cpu(ver_words[2]), + le16_to_cpu(ver_words[3])); /* EF10 may have multiple datapath firmware variants within a * single version. Report which variants are running. @@ -1427,9 +1431,9 @@ void efx_mcdi_print_fwver(struct efx_nic *efx, char *buf, size_t len) if (efx_nic_rev(efx) >= EFX_REV_HUNT_A0) { struct efx_ef10_nic_data *nic_data = efx->nic_data; - offset += snprintf(buf + offset, len - offset, " rx%x tx%x", - nic_data->rx_dpcpu_fw_id, - nic_data->tx_dpcpu_fw_id); + offset += scnprintf(buf + offset, len - offset, " rx%x tx%x", + nic_data->rx_dpcpu_fw_id, + nic_data->tx_dpcpu_fw_id); /* It's theoretically possible for the string to exceed 31 * characters, though in practice the first three version |