syzbot


KMSAN: uninit-value in netif_skb_features (4)

Status: upstream: reported C repro on 2025/10/07 06:40
Subsystems: bridge
[Documentation on labels]
Reported-by: syzbot+1543a7d954d9c6d00407@syzkaller.appspotmail.com
First crash: 151d, last: 2d11h
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] [net?] KMSAN: uninit-value in netif_skb_features (4) 0 (2) 2026/02/15 14:46
[syzbot] Monthly bridge report (Jan 2026) 0 (1) 2026/01/19 08:19
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: kernel-infoleak in copyout (2) net 17 C 6723 999d 2167d 22/29 fixed on 2023/06/08 14:41
upstream KMSAN: uninit-value in netif_skb_features (2) net 7 C 9 806d 894d 25/29 fixed on 2024/01/30 15:47
upstream KMSAN: kernel-infoleak in _copy_to_iter (7) net 21 C 138977 1102d 1454d 22/29 fixed on 2023/02/24 13:50
upstream KMSAN: uninit-value in netif_skb_features (3) net 7 1 375d 375d 0/29 auto-obsoleted due to no activity on 2025/05/29 13:17
upstream KMSAN: uninit-value in netif_skb_features net 7 C 119 2855d 2881d 5/29 fixed on 2018/05/08 18:30

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in gso_features_check net/core/dev.c:3804 [inline]
BUG: KMSAN: uninit-value in netif_skb_features+0x6fb/0x1870 net/core/dev.c:3828
 gso_features_check net/core/dev.c:3804 [inline]
 netif_skb_features+0x6fb/0x1870 net/core/dev.c:3828
 validate_xmit_skb+0xb6/0x2400 net/core/dev.c:4003
 validate_xmit_skb_list+0xd4/0x320 net/core/dev.c:4065
 sch_direct_xmit+0xd4/0xcf0 net/sched/sch_generic.c:332
 __dev_xmit_skb net/core/dev.c:4179 [inline]
 __dev_queue_xmit+0x3016/0x5a50 net/core/dev.c:4795
 dev_queue_xmit include/linux/netdevice.h:3384 [inline]
 packet_xmit+0x8f/0x710 net/packet/af_packet.c:275
 packet_snd net/packet/af_packet.c:3077 [inline]
 packet_sendmsg+0x91d9/0xa320 net/packet/af_packet.c:3109
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0xfe7/0x1080 net/socket.c:2592
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2681
 x64_sys_call+0x1e20/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4466 [inline]
 slab_alloc_node mm/slub.c:4788 [inline]
 kmem_cache_alloc_node_noprof+0x3cd/0x12d0 mm/slub.c:4840
 kmalloc_reserve net/core/skbuff.c:613 [inline]
 __alloc_skb+0x855/0x1190 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6750
 sock_alloc_send_pskb+0xacb/0xc60 net/core/sock.c:2995
 packet_alloc_skb net/packet/af_packet.c:2927 [inline]
 packet_snd net/packet/af_packet.c:3020 [inline]
 packet_sendmsg+0x7477/0xa320 net/packet/af_packet.c:3109
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0xfe7/0x1080 net/socket.c:2592
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2681
 x64_sys_call+0x1e20/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 6045 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
=====================================================

Crashes (55):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/15 14:45 upstream ca4ee40bf13d 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/28 14:21 upstream 4d349ee5c778 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/27 09:54 upstream a75cb869a8cc a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/26 20:35 upstream f4d0ec0aa20d ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/25 05:20 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/25 05:20 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/22 17:23 upstream 32a92f8c8932 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/22 17:23 upstream 32a92f8c8932 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/21 14:54 upstream d79526b89571 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/21 14:54 upstream d79526b89571 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/21 14:53 upstream d79526b89571 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/21 14:53 upstream d79526b89571 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/19 00:29 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/18 18:24 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/18 18:24 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/18 02:36 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/18 02:35 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/16 04:17 upstream bb7a3fc2c976 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/16 04:16 upstream bb7a3fc2c976 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/15 04:20 upstream ca4ee40bf13d 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/15 04:20 upstream ca4ee40bf13d 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/13 20:37 upstream cee73b1e840c 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/13 12:35 upstream cee73b1e840c 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/13 12:35 upstream cee73b1e840c 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/01/04 16:15 upstream aacb0a6d604a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/01/04 16:07 upstream aacb0a6d604a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/01/04 16:01 upstream aacb0a6d604a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2025/11/15 22:45 upstream f824272b6e3f f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2025/10/03 06:32 upstream e406d57be7bd 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in netif_skb_features
2026/02/28 19:21 upstream 4d349ee5c778 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/27 22:17 upstream a75cb869a8cc 2cf092b8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/27 11:46 upstream a75cb869a8cc a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/27 01:17 upstream f4d0ec0aa20d ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/25 07:26 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/22 18:57 upstream 32a92f8c8932 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/22 18:56 upstream 32a92f8c8932 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/21 17:34 upstream a95f71ad3e2e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/21 17:29 upstream a95f71ad3e2e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/21 17:29 upstream a95f71ad3e2e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/19 02:26 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/18 05:25 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/18 05:25 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/16 08:16 upstream 26a4cfaff82a 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/16 08:15 upstream 26a4cfaff82a 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/15 05:45 upstream 64275e9fda37 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/14 02:15 upstream cd7a5651db26 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/13 13:12 upstream cee73b1e840c 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/02/13 13:12 upstream cee73b1e840c 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
2026/01/29 17:08 upstream 8dfce8991b95 aeb6fdd5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in netif_skb_features
* Struck through repros no longer work on HEAD.