From: Jason A. Donenfeld <Jason@xxxxxxxxx> [ Upstream commit e6cb8769452e8236b52134e5cb4a18b8f5986932 ] With char becoming unsigned by default, and with `char` alone being ambiguous and based on architecture, we get a warning when assigning the unchecked output of hex_to_bin() to that unsigned char. Mark `key` as a `u8`, which matches the struct's type, and then check each call to hex_to_bin() before casting. Cc: Kalle Valo <kvalo@xxxxxxxxxx> Cc: linux-wireless@xxxxxxxxxxxxxxx Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxx> Link: https://lore.kernel.org/r/20221024162843.535921-1-Jason@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/wireless/cisco/airo.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/cisco/airo.c b/drivers/net/wireless/cisco/airo.c index 10daef81c355..fb2c35bd73bb 100644 --- a/drivers/net/wireless/cisco/airo.c +++ b/drivers/net/wireless/cisco/airo.c @@ -5232,7 +5232,7 @@ static int get_wep_tx_idx(struct airo_info *ai) return -1; } -static int set_wep_key(struct airo_info *ai, u16 index, const char *key, +static int set_wep_key(struct airo_info *ai, u16 index, const u8 *key, u16 keylen, int perm, int lock) { static const unsigned char macaddr[ETH_ALEN] = { 0x01, 0, 0, 0, 0, 0 }; @@ -5283,7 +5283,7 @@ static void proc_wepkey_on_close(struct inode *inode, struct file *file) struct net_device *dev = pde_data(inode); struct airo_info *ai = dev->ml_priv; int i, rc; - char key[16]; + u8 key[16]; u16 index = 0; int j = 0; @@ -5311,12 +5311,22 @@ static void proc_wepkey_on_close(struct inode *inode, struct file *file) } for (i = 0; i < 16*3 && data->wbuffer[i+j]; i++) { + int val; + + if (i % 3 == 2) + continue; + + val = hex_to_bin(data->wbuffer[i+j]); + if (val < 0) { + airo_print_err(ai->dev->name, "WebKey passed invalid key hex"); + return; + } switch(i%3) { case 0: - key[i/3] = hex_to_bin(data->wbuffer[i+j])<<4; + key[i/3] = (u8)val << 4; break; case 1: - key[i/3] |= hex_to_bin(data->wbuffer[i+j]); + key[i/3] |= (u8)val; break; } } -- 2.35.1