KMSAN: uninit-value in ieee80211_sta_tx_notify

KMSAN: uninit-value in ieee80211_sta_tx_notify

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    5edb1df2 kmsan: drop the _nosanitize string functions
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=1279b1c0500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4991d22eb136035c
dashboard link: https://syzkaller.appspot.com/bug?extid=beae481026cb095addca
compiler:       clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+beae481026cb095addca@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in ieee80211_ac_from_tid net/mac80211/ieee80211_i.h:2034 [inline]
BUG: KMSAN: uninit-value in ieee80211_sta_tx_wmm_ac_notify net/mac80211/mlme.c:2490 [inline]
BUG: KMSAN: uninit-value in ieee80211_sta_tx_notify+0x4be/0xda0 net/mac80211/mlme.c:2522
CPU: 1 PID: 8613 Comm: kworker/u4:1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: phy18 ieee80211_beacon_connection_loss_work
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:201
 ieee80211_ac_from_tid net/mac80211/ieee80211_i.h:2034 [inline]
 ieee80211_sta_tx_wmm_ac_notify net/mac80211/mlme.c:2490 [inline]
 ieee80211_sta_tx_notify+0x4be/0xda0 net/mac80211/mlme.c:2522
 __ieee80211_tx_status+0x2d3b/0x4450 net/mac80211/status.c:1013
 ieee80211_tx_status+0x223/0x270 net/mac80211/status.c:1129
 ieee80211_tasklet_handler+0x34e/0x3c0 net/mac80211/main.c:239
 tasklet_action_common+0x416/0x6a0 kernel/softirq.c:562
 tasklet_action+0x30/0x40 kernel/softirq.c:580
 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:299
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:23 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 do_softirq_own_stack+0x7c/0xa0 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:344 [inline]
 __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:196
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 __ieee80211_tx_skb_tid_band+0x28e/0x390 net/mac80211/tx.c:5352
 ieee80211_tx_skb_tid net/mac80211/ieee80211_i.h:2003 [inline]
 ieee80211_tx_skb net/mac80211/ieee80211_i.h:2012 [inline]
 ieee80211_send_nullfunc+0x59a/0x6d0 net/mac80211/mlme.c:1095
 ieee80211_mgd_probe_ap_send+0x897/0xb40 net/mac80211/mlme.c:2593
 ieee80211_mgd_probe_ap+0x6b3/0x760 net/mac80211/mlme.c:2669
 ieee80211_beacon_connection_loss_work+0x156/0x270 net/mac80211/mlme.c:2788
 process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
 worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
 kthread+0x551/0x590 kernel/kthread.c:293
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:143
 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:268 [inline]
 kmsan_alloc_page+0xc5/0x1a0 mm/kmsan/kmsan_shadow.c:292
 __alloc_pages_nodemask+0xf34/0x1120 mm/page_alloc.c:4927
 __alloc_pages include/linux/gfp.h:509 [inline]
 __alloc_pages_node include/linux/gfp.h:522 [inline]
 alloc_pages_node include/linux/gfp.h:536 [inline]
 __page_frag_cache_refill mm/page_alloc.c:5002 [inline]
 page_frag_alloc+0x35b/0x880 mm/page_alloc.c:5032
 __netdev_alloc_skb+0xc3d/0xc90 net/core/skbuff.c:456
 netdev_alloc_skb include/linux/skbuff.h:2821 [inline]
 dev_alloc_skb include/linux/skbuff.h:2834 [inline]
 __ieee80211_beacon_get+0x37e3/0x4df0 net/mac80211/tx.c:4819
 ieee80211_beacon_get_tim+0x109/0x800 net/mac80211/tx.c:4933
 ieee80211_beacon_get include/net/mac80211.h:4845 [inline]
 mac80211_hwsim_beacon_tx+0x1c3/0xb80 drivers/net/wireless/mac80211_hwsim.c:1676
 __iterate_interfaces net/mac80211/util.c:737 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x40a/0x610 net/mac80211/util.c:773
 mac80211_hwsim_beacon+0x11d/0x2e0 drivers/net/wireless/mac80211_hwsim.c:1717
 __run_hrtimer+0x7cd/0xf00 kernel/time/hrtimer.c:1524
 __hrtimer_run_queues kernel/time/hrtimer.c:1588 [inline]
 hrtimer_run_softirq+0x3bf/0x690 kernel/time/hrtimer.c:1605
 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:299
=====================================================


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