4.16-stable review patch. If anyone has any objections, please let me know.
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From: Eric Biggers ebiggers@google.com
commit 814596495dd2b9d4aab92d8f89cf19060d25d2ea upstream.
wiphy names were recently limited to 128 bytes by commit a7cfebcb7594 ("cfg80211: limit wiphy names to 128 bytes"). As it turns out though, this isn't sufficient because dev_vprintk_emit() needs the syslog header string "SUBSYSTEM=ieee80211\0DEVICE=+ieee80211:$devname" to fit into 128 bytes. This triggered the "device/subsystem name too long" WARN when the device name was >= 90 bytes. As before, this was reproduced by syzbot by sending an HWSIM_CMD_NEW_RADIO command to the MAC80211_HWSIM generic netlink family.
Fix it by further limiting wiphy names to 64 bytes.
Reported-by: syzbot+e64565577af34b3768dc@syzkaller.appspotmail.com Fixes: a7cfebcb7594 ("cfg80211: limit wiphy names to 128 bytes") Signed-off-by: Eric Biggers ebiggers@google.com Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/uapi/linux/nl80211.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -2618,7 +2618,7 @@ enum nl80211_attrs { #define NL80211_ATTR_KEYS NL80211_ATTR_KEYS #define NL80211_ATTR_FEATURE_FLAGS NL80211_ATTR_FEATURE_FLAGS
-#define NL80211_WIPHY_NAME_MAXLEN 128 +#define NL80211_WIPHY_NAME_MAXLEN 64
#define NL80211_MAX_SUPP_RATES 32 #define NL80211_MAX_SUPP_HT_RATES 77