From: Eric Dumazet Date: Thu, 8 Jan 2026 10:19:27 +0000 (+0000) Subject: wifi: avoid kernel-infoleak from struct iw_point X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=21cbf883d073abbfe09e3924466aa5e0449e7261;p=thirdparty%2Fkernel%2Flinux.git wifi: avoid kernel-infoleak from struct iw_point struct iw_point has a 32bit hole on 64bit arches. struct iw_point { void __user *pointer; /* Pointer to the data (in user space) */ __u16 length; /* number of fields or size in bytes */ __u16 flags; /* Optional params */ }; Make sure to zero the structure to avoid disclosing 32bits of kernel data to user space. Fixes: 87de87d5e47f ("wext: Dispatch and handle compat ioctls entirely in net/wireless/wext.c") Reported-by: syzbot+bfc7323743ca6dbcc3d3@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/695f83f3.050a0220.1c677c.0392.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260108101927.857582-1-edumazet@google.com Signed-off-by: Johannes Berg --- diff --git a/net/wireless/wext-core.c b/net/wireless/wext-core.c index c32a7c6903d5..7b8e94214b07 100644 --- a/net/wireless/wext-core.c +++ b/net/wireless/wext-core.c @@ -1101,6 +1101,10 @@ static int compat_standard_call(struct net_device *dev, return ioctl_standard_call(dev, iwr, cmd, info, handler); iwp_compat = (struct compat_iw_point *) &iwr->u.data; + + /* struct iw_point has a 32bit hole on 64bit arches. */ + memset(&iwp, 0, sizeof(iwp)); + iwp.pointer = compat_ptr(iwp_compat->pointer); iwp.length = iwp_compat->length; iwp.flags = iwp_compat->flags; diff --git a/net/wireless/wext-priv.c b/net/wireless/wext-priv.c index 674d426a9d24..37d1147019c2 100644 --- a/net/wireless/wext-priv.c +++ b/net/wireless/wext-priv.c @@ -228,6 +228,10 @@ int compat_private_call(struct net_device *dev, struct iwreq *iwr, struct iw_point iwp; iwp_compat = (struct compat_iw_point *) &iwr->u.data; + + /* struct iw_point has a 32bit hole on 64bit arches. */ + memset(&iwp, 0, sizeof(iwp)); + iwp.pointer = compat_ptr(iwp_compat->pointer); iwp.length = iwp_compat->length; iwp.flags = iwp_compat->flags;