Subject: Re: [syzbot] [wireless?] KMSAN: uninit-value in ieee80211_amsdu_to_8023s

From: syzbot <[email-masked]>
Date: Sun, 03 Mar 2024 23:23:24 -0800

syzbot has found a reproducer for the following issue on:

HEAD commit:    58c806d867bf Merge tag 'phy-fixes2-6.8' of git://git.kerne..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12374c96180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=80c7a82a572c0de3
dashboard link: https://syzkaller.appspot.com/bug?extid=d050d437fe47d479d210
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14227612180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=134411a2180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b2b0ed9886ae/disk-58c806d8.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/372dff1b6033/vmlinux-58c806d8.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d2b87ebe3e7b/bzImage-58c806d8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

=====================================================
BUG: KMSAN: uninit-value in ieee80211_amsdu_to_8023s+0x8c1/0x2d40 net/wireless/util.c:856
 ieee80211_amsdu_to_8023s+0x8c1/0x2d40 net/wireless/util.c:856
 __ieee80211_rx_h_amsdu+0x91a/0x13b0 net/mac80211/rx.c:3047
 ieee80211_rx_h_amsdu net/mac80211/rx.c:3133 [inline]
 ieee80211_rx_handlers+0x571a/0x10c40 net/mac80211/rx.c:4141
 ieee80211_invoke_rx_handlers net/mac80211/rx.c:4185 [inline]
 ieee80211_prepare_and_rx_handle+0x5640/0x9690 net/mac80211/rx.c:5033
 __ieee80211_rx_handle_packet net/mac80211/rx.c:5239 [inline]
 ieee80211_rx_list+0x642c/0x65d0 net/mac80211/rx.c:5410
 ieee80211_rx_napi+0x84/0x3e0 net/mac80211/rx.c:5433
 ieee80211_rx include/net/mac80211.h:4983 [inline]
 ieee80211_tasklet_handler+0x19f/0x330 net/mac80211/main.c:318
 tasklet_action_common+0x391/0xd30 kernel/softirq.c:780
 tasklet_action+0x26/0x30 kernel/softirq.c:805
 __do_softirq+0x1b7/0x7c5 kernel/softirq.c:553
 run_ksoftirqd+0x24/0x40 kernel/softirq.c:921
 smpboot_thread_fn+0x558/0xa60 kernel/smpboot.c:164
 kthread+0x3ed/0x550 kernel/kthread.c:388
 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:243

Local variable hdr created at:
 ieee80211_amsdu_to_8023s+0x5b/0x2d40 net/wireless/util.c:832
 __ieee80211_rx_h_amsdu+0x91a/0x13b0 net/mac80211/rx.c:3047

CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 6.8.0-rc6-syzkaller-00278-g58c806d867bf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
=====================================================

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#syz test: git://repo/address.git branch-or-commit-hash
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