[PATCH AUTOSEL 6.6 055/139] wifi: mwifiex: Fix memcpy() field-spanning write warning in mwifiex_cmd_802_11_scan_ext()

Sasha Levin
2024-09-25T12:13:50Z

From: "Gustavo A. R. Silva" <gustavoars@kernel.org>

[ Upstream commit 498365e52bebcbc36a93279fe7e9d6aec8479cee ]

Replace one-element array with a flexible-array member in
`struct host_cmd_ds_802_11_scan_ext`.

With this, fix the following warning:

elo 16 17:51:58 surfacebook kernel: ------------[ cut here ]------------
elo 16 17:51:58 surfacebook kernel: memcpy: detected field-spanning write (size 243) of single field "ext_scan->tlv_buffer" at drivers/net/wireless/marvell/mwifiex/scan.c:2239 (size 1)
elo 16 17:51:58 surfacebook kernel: WARNING: CPU: 0 PID: 498 at drivers/net/wireless/marvell/mwifiex/scan.c:2239 mwifiex_cmd_802_11_scan_ext+0x83/0x90 [mwifiex]

Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Closes: https://lore.kernel.org/linux-hardening/ZsZNgfnEwOcPdCly@black.fi.intel.com/
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/ZsZa5xRcsLq9D+RX@elsanto
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/marvell/mwifiex/fw.h | 2 +-
drivers/net/wireless/marvell/mwifiex/scan.c | 3 +--
2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/fw.h b/drivers/net/wireless/marvell/mwifiex/fw.h
index 62f3c9a52a1d5..a3be37526697b 100644
--- a/drivers/net/wireless/marvell/mwifiex/fw.h
+++ b/drivers/net/wireless/marvell/mwifiex/fw.h
@@ -1587,7 +1587,7 @@ struct host_cmd_ds_802_11_scan_rsp {

struct host_cmd_ds_802_11_scan_ext {
u32 reserved;
- u8 tlv_buffer[1];
+ u8 tlv_buffer[];
} __packed;

struct mwifiex_ie_types_bss_mode {
diff --git a/drivers/net/wireless/marvell/mwifiex/scan.c b/drivers/net/wireless/marvell/mwifiex/scan.c
index 72904c275461e..5be817d9854a6 100644
--- a/drivers/net/wireless/marvell/mwifiex/scan.c
+++ b/drivers/net/wireless/marvell/mwifiex/scan.c
@@ -2543,8 +2543,7 @@ int mwifiex_ret_802_11_scan_ext(struct mwifiex_private *priv,
ext_scan_resp = &resp->params.ext_scan;

tlv = (void *)ext_scan_resp->tlv_buffer;
- buf_left = le16_to_cpu(resp->size) - (sizeof(*ext_scan_resp) + S_DS_GEN
- - 1);
+ buf_left = le16_to_cpu(resp->size) - (sizeof(*ext_scan_resp) + S_DS_GEN);

while (buf_left >= sizeof(struct mwifiex_ie_types_header)) {
type = le16_to_cpu(tlv->type);
--
2.43.0