[PATCH 5.4 93/96] mwifiex: Fix possible buffer overflows in mwifiex_ret_wmm_get_status()

From: Greg Kroah-Hartman
Date: Thu Feb 13 2020 - 10:43:49 EST


From: Qing Xu <m1s5p6688@xxxxxxxxx>

[ Upstream commit 3a9b153c5591548612c3955c9600a98150c81875 ]

mwifiex_ret_wmm_get_status() calls memcpy() without checking the
destination size.Since the source is given from remote AP which
contains illegal wmm elements , this may trigger a heap buffer
overflow.
Fix it by putting the length check before calling memcpy().

Signed-off-by: Qing Xu <m1s5p6688@xxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/marvell/mwifiex/wmm.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/net/wireless/marvell/mwifiex/wmm.c b/drivers/net/wireless/marvell/mwifiex/wmm.c
index 41f0231376c01..132f9e8ed68c1 100644
--- a/drivers/net/wireless/marvell/mwifiex/wmm.c
+++ b/drivers/net/wireless/marvell/mwifiex/wmm.c
@@ -970,6 +970,10 @@ int mwifiex_ret_wmm_get_status(struct mwifiex_private *priv,
"WMM Parameter Set Count: %d\n",
wmm_param_ie->qos_info_bitmap & mask);

+ if (wmm_param_ie->vend_hdr.len + 2 >
+ sizeof(struct ieee_types_wmm_parameter))
+ break;
+
memcpy((u8 *) &priv->curr_bss_params.bss_descriptor.
wmm_ie, wmm_param_ie,
wmm_param_ie->vend_hdr.len + 2);
--
2.20.1