p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

cfg80211: fix and clean up cfg80211_gen_new_bssid() 

Fix cfg80211_gen_new_bssid() to not rely on u64 modulo arithmetic,
which isn't needed since we really just want to mask there. Also,
clean it up to calculate the mask only once and use GENMASK_ULL()
instead of open-coding the mask calculation.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2019-02-11 16:03:12 +01:00
parent 7388afe091
commit 5d4071abd9
1 changed files with 8 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
include/net/cfg80211.h
View File

@ -5475,22 +5475,20 @@ cfg80211_inform_bss_frame(struct wiphy *wiphy,
* @bssid: transmitter BSSID
* @max_bssid: max BSSID indicator, taken from Multiple BSSID element
* @mbssid_index: BSSID index, taken from Multiple BSSID index element
* @new_bssid_addr: address of the resulting BSSID
* @new_bssid: calculated nontransmitted BSSID
*/
static inline void cfg80211_gen_new_bssid(const u8 *bssid, u8 max_bssid,
u8 mbssid_index, u8 *new_bssid_addr)
u8 mbssid_index, u8 *new_bssid)
{
u64 bssid_tmp, new_bssid;
u64 lsb_n;
u64 bssid_u64 = ether_addr_to_u64(bssid);
u64 mask = GENMASK_ULL(max_bssid - 1, 0);
u64 new_bssid_u64;
bssid_tmp = ether_addr_to_u64(bssid);
new_bssid_u64 = bssid_u64 & ~mask;
lsb_n = bssid_tmp & ((1 << max_bssid) - 1);
new_bssid = bssid_tmp;
new_bssid &= ~((1 << max_bssid) - 1);
new_bssid |= (lsb_n + mbssid_index) % (1 << max_bssid);
new_bssid_u64 |= ((bssid_u64 & mask) + mbssid_index) & mask;
u64_to_ether_addr(new_bssid, new_bssid_addr);
u64_to_ether_addr(new_bssid_u64, new_bssid);
}
/**