From: Alper Nebi Yasak Date: Mon, 7 Oct 2024 22:20:54 +0000 (+0300) Subject: wifi: mwifiex: Fix memcpy() field-spanning write warning in mwifiex_config_scan() X-Git-Tag: v6.13-rc1~135^2~195^2~49 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d241a139c2e9f8a479f25c75ebd5391e6a448500;p=thirdparty%2Fkernel%2Flinux.git wifi: mwifiex: Fix memcpy() field-spanning write warning in mwifiex_config_scan() Replace one-element array with a flexible-array member in `struct mwifiex_ie_types_wildcard_ssid_params` to fix the following warning on a MT8173 Chromebook (mt8173-elm-hana): [ 356.775250] ------------[ cut here ]------------ [ 356.784543] memcpy: detected field-spanning write (size 6) of single field "wildcard_ssid_tlv->ssid" at drivers/net/wireless/marvell/mwifiex/scan.c:904 (size 1) [ 356.813403] WARNING: CPU: 3 PID: 742 at drivers/net/wireless/marvell/mwifiex/scan.c:904 mwifiex_scan_networks+0x4fc/0xf28 [mwifiex] The "(size 6)" above is exactly the length of the SSID of the network this device was connected to. The source of the warning looks like: ssid_len = user_scan_in->ssid_list[i].ssid_len; [...] memcpy(wildcard_ssid_tlv->ssid, user_scan_in->ssid_list[i].ssid, ssid_len); There is a #define WILDCARD_SSID_TLV_MAX_SIZE that uses sizeof() on this struct, but it already didn't account for the size of the one-element array, so it doesn't need to be changed. Fixes: 5e6e3a92b9a4 ("wireless: mwifiex: initial commit for Marvell mwifiex driver") Signed-off-by: Alper Nebi Yasak Acked-by: Brian Norris Signed-off-by: Kalle Valo Link: https://patch.msgid.link/20241007222301.24154-1-alpernebiyasak@gmail.com --- diff --git a/drivers/net/wireless/marvell/mwifiex/fw.h b/drivers/net/wireless/marvell/mwifiex/fw.h index d03129d5d24e3..4a96281792cc1 100644 --- a/drivers/net/wireless/marvell/mwifiex/fw.h +++ b/drivers/net/wireless/marvell/mwifiex/fw.h @@ -875,7 +875,7 @@ struct mwifiex_ietypes_chanstats { struct mwifiex_ie_types_wildcard_ssid_params { struct mwifiex_ie_types_header header; u8 max_ssid_length; - u8 ssid[1]; + u8 ssid[]; } __packed; #define TSF_DATA_SIZE 8