| Message ID | 20210405053306.3437-1-penguin-kernel@I-love.SAKURA.ne.jp |
|---|---|
| State | New |
| Headers | show |
| Series | batman-adv: initialize "struct batadv_tvlv_tt_vlan_data"->reserved field | expand |
On Monday, 5 April 2021 12:02:02 CEST Tetsuo Handa wrote: [...] > > Thanks but this patch is incomplete. Please also fix > > batadv_tt_prepare_tvlv_global_data (exactly the same way) > > Indeed. Hmm, batadv_send_tt_request() is already using kzalloc(). > Which approach ( "->reserved = 0" or "kzalloc()") do you prefer for > batadv_tt_prepare_tvlv_global_data() and batadv_tt_prepare_tvlv_local_data() ? Lets stick with the approach you've used in your v1 version - "->reserved = 0" Kind regards, Sven
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c index f8761281aab0..eb82576557e6 100644 --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -973,6 +973,7 @@ batadv_tt_prepare_tvlv_local_data(struct batadv_priv *bat_priv, tt_vlan->vid = htons(vlan->vid); tt_vlan->crc = htonl(vlan->tt.crc); + tt_vlan->reserved = 0; tt_vlan++; }
KMSAN found uninitialized value at batadv_tt_prepare_tvlv_local_data() [1], for commit ced72933a5e8ab52 ("batman-adv: use CRC32C instead of CRC16 in TT code") inserted 'reserved' field into "struct batadv_tvlv_tt_data" and commit 7ea7b4a142758dea ("batman-adv: make the TT CRC logic VLAN specific") moved that field to "struct batadv_tvlv_tt_vlan_data" but left that field uninitialized. Although this patch passed "#syz test:" check, there might be similar bugs remaining. It might be better to proactively use __GFP_ZERO than trying to find uninitialized fields in this module. [1] https://syzkaller.appspot.com/bug?id=07f3e6dba96f0eb3cabab986adcd8a58b9bdbe9d Reported-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com> Tested-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Fixes: ced72933a5e8ab52 ("batman-adv: use CRC32C instead of CRC16 in TT code") Fixes: 7ea7b4a142758dea ("batman-adv: make the TT CRC logic VLAN specific") --- net/batman-adv/translation-table.c | 1 + 1 file changed, 1 insertion(+)