[syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    4871b7cb27f4 Merge tag 'v6.16-rc6-smb3-client-fixes' of gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15bbe38c580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5227c65742122bdd
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
userspace arch: i386

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e2e34a7999ba/disk-4871b7cb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/834fdc8dbc07/vmlinux-4871b7cb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/617fadfb9a8e/bzImage-4871b7cb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9a4fbb77c9d4aacd3388@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_l2_rcv_msg+0x213/0x320 net/tipc/bearer.c:668
 __netif_receive_skb_list_ptype net/core/dev.c:6025 [inline]
 __netif_receive_skb_list_core+0x133b/0x16b0 net/core/dev.c:6067
 __netif_receive_skb_list net/core/dev.c:6119 [inline]
 netif_receive_skb_list_internal+0xee7/0x1530 net/core/dev.c:6210
 gro_normal_list include/net/gro.h:532 [inline]
 napi_complete_done+0x3fb/0x7d0 net/core/dev.c:6580
 napi_complete include/linux/netdevice.h:588 [inline]
 tun_get_user+0x4ac4/0x6b40 drivers/net/tun.c:1909
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1984
 do_iter_readv_writev+0x94a/0xba0 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __ia32_sys_writev+0x9c/0xf0 fs/read_write.c:1168
 ia32_sys_call+0x3f2a/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:147
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4154 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4249
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 napi_alloc_skb+0xc1/0x740 net/core/skbuff.c:812
 napi_get_frags+0xab/0x250 net/core/gro.c:673
 tun_napi_alloc_frags drivers/net/tun.c:1404 [inline]
 tun_get_user+0x1246/0x6b40 drivers/net/tun.c:1772
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1984
 do_iter_readv_writev+0x94a/0xba0 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __ia32_sys_writev+0x9c/0xf0 fs/read_write.c:1168
 ia32_sys_call+0x3f2a/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:147
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 15202 Comm: syz.3.3410 Not tainted 6.16.0-rc6-syzkaller-00253-g4871b7cb27f4 #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
=====================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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syzbot will keep track of this issue. See:
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If you want to undo deduplication, reply with:
#syz undup

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    89748acdf226 Merge tag 'drm-next-2025-08-01' of https://gi..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1395bcf0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7ff65239b4835001
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1625ff82580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=131bb834580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ce090dd92dc2/disk-89748acd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/32b5903a7759/vmlinux-89748acd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/dc68a867773d/bzImage-89748acd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9a4fbb77c9d4aacd3388@syzkaller.appspotmail.com

tipc: Started in network mode
tipc: Node identity 4689370d27fe, cluster identity 4711
tipc: Enabled bearer <eth:syzkaller0>, priority 0
=====================================================
BUG: KMSAN: uninit-value in tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_l2_rcv_msg+0x213/0x320 net/tipc/bearer.c:668
 __netif_receive_skb_list_ptype net/core/dev.c:6027 [inline]
 __netif_receive_skb_list_core+0x133b/0x16b0 net/core/dev.c:6069
 __netif_receive_skb_list net/core/dev.c:6121 [inline]
 netif_receive_skb_list_internal+0xee7/0x1530 net/core/dev.c:6212
 gro_normal_list include/net/gro.h:532 [inline]
 gro_flush_normal include/net/gro.h:540 [inline]
 napi_complete_done+0x3fb/0x7d0 net/core/dev.c:6581
 napi_complete include/linux/netdevice.h:589 [inline]
 tun_get_user+0x4c0d/0x6ca0 drivers/net/tun.c:1921
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1996
 do_iter_readv_writev+0x947/0xba0 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 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:4186 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4281
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:578
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:669
 napi_alloc_skb+0xc1/0x740 net/core/skbuff.c:811
 napi_get_frags+0xab/0x250 net/core/gro.c:673
 tun_napi_alloc_frags drivers/net/tun.c:1404 [inline]
 tun_get_user+0x134f/0x6ca0 drivers/net/tun.c:1784
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1996
 do_iter_readv_writev+0x947/0xba0 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 5808 Comm: syz-executor123 Not tainted 6.16.0-syzkaller-10499-g89748acdf226 #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
=====================================================


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+9a4fbb77c9d4aacd3388@syzkaller.appspotmail.com
Tested-by: syzbot+9a4fbb77c9d4aacd3388@syzkaller.appspotmail.com

Tested on:

commit:         e8442d5b Merge tag 'sound-6.17-rc7' of git://git.kerne..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=134fc712580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1b093ccee5a9e08c
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12e79c7c580000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

net/tipc/node.c:2121:3: error: void function 'tipc_rcv' should not return a value [-Wreturn-mismatch]


Tested on:

commit:         3b08f56f Merge tag 'x86-urgent-2025-09-20' of git://gi..
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=7ff65239b4835001
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=101470e2580000

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: uninit-value in tipc_rcv

=====================================================
BUG: KMSAN: uninit-value in tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_l2_rcv_msg+0x213/0x320 net/tipc/bearer.c:668
 __netif_receive_skb_list_ptype net/core/dev.c:6127 [inline]
 __netif_receive_skb_list_core+0x133e/0x16b0 net/core/dev.c:6169
 __netif_receive_skb_list net/core/dev.c:6221 [inline]
 netif_receive_skb_list_internal+0xee7/0x1530 net/core/dev.c:6312
 gro_normal_list include/net/gro.h:524 [inline]
 gro_flush_normal include/net/gro.h:532 [inline]
 napi_complete_done+0x3fb/0x7d0 net/core/dev.c:6681
 napi_complete include/linux/netdevice.h:589 [inline]
 tun_get_user+0x5953/0x6d70 drivers/net/tun.c:1924
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
 do_iter_readv_writev+0x9e1/0xc20 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 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:4977 [inline]
 slab_alloc_node mm/slub.c:5280 [inline]
 kmem_cache_alloc_node_noprof+0x989/0x16b0 mm/slub.c:5332
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 napi_alloc_skb+0xc1/0x740 net/core/skbuff.c:812
 napi_get_frags+0xab/0x250 net/core/gro.c:681
 tun_napi_alloc_frags drivers/net/tun.c:1404 [inline]
 tun_get_user+0x1352/0x6d70 drivers/net/tun.c:1784
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
 do_iter_readv_writev+0x9e1/0xc20 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 6553 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
=====================================================


Tested on:

commit:         4a0c9b33 Merge tag 'probes-fixes-v6.18-rc4' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=123c7012580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2901a6a99b67fbcc
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=104a332f980000

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in tipc_buf_acquire

tipc: Started in network mode
tipc: Node identity 5e9377e8cc82, cluster identity 4711
tipc: tipc_buf_acquire
skbuff: skb_over_panic: text:ffffffff8fe53c01 len:76 put:76 head:0000000000000000 data:00000000000000d0 tail:0x11c end:0x0 dev:<NULL>
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:212!
Oops: invalid opcode: 0000 [#1] SMP PTI
CPU: 0 UID: 0 PID: 6600 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:skb_panic+0x2d3/0x340 net/core/skbuff.c:212
Code: d0 44 8b 45 cc 4c 8b 8d 58 ff ff ff 41 52 ff b5 70 ff ff ff ff b5 68 ff ff ff ff b5 60 ff ff ff e8 d2 5d ee ff 48 83 c4 20 90 <0f> 0b e8 c6 8f 69 01 48 83 7d a0 00 0f 84 6a ff ff ff 48 8b 7d c0
RSP: 0018:ffff88801f8cf0e8 EFLAGS: 00010286
RAX: 0000000000000085 RBX: ffff88811718cda0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffff88801f8cf1a0 R08: ffffea000000000f R09: 0000000000000000
R10: ffff888237c7e028 R11: ffff88823f278d40 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f26537fe6c0(0000) GS:ffff8881aaf8d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2654574620 CR3: 0000000049ab8000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 skb_over_panic net/core/skbuff.c:217 [inline]
 skb_put+0x1f5/0x250 net/core/skbuff.c:2583
 tipc_buf_acquire+0x141/0x1b0 net/tipc/msg.c:77
 tipc_disc_create+0x12f/0x870 net/tipc/discover.c:359
 tipc_enable_bearer net/tipc/bearer.c:348 [inline]
 __tipc_nl_bearer_enable+0x1f61/0x2a00 net/tipc/bearer.c:1047
 __tipc_nl_compat_doit net/tipc/netlink_compat.c:371 [inline]
 tipc_nl_compat_doit+0x67b/0xa10 net/tipc/netlink_compat.c:393
 tipc_nl_compat_handle net/tipc/netlink_compat.c:-1 [inline]
 tipc_nl_compat_recv+0x1007/0x1670 net/tipc/netlink_compat.c:1321
 genl_family_rcv_msg_doit+0x338/0x3f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0xacf/0xc10 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2552
 genl_rcv+0x41/0x60 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0xf04/0x12b0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2630
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2684
 __sys_sendmsg net/socket.c:2716 [inline]
 __do_sys_sendmsg net/socket.c:2721 [inline]
 __se_sys_sendmsg net/socket.c:2719 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2719
 x64_sys_call+0x1dfd/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f265458eb69
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f26537fe038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f26547b5fa0 RCX: 00007f265458eb69
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000006
RBP: 00007f2654611df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f26547b5fa0 R15: 00007ffe744cefd8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:skb_panic+0x2d3/0x340 net/core/skbuff.c:212
Code: d0 44 8b 45 cc 4c 8b 8d 58 ff ff ff 41 52 ff b5 70 ff ff ff ff b5 68 ff ff ff ff b5 60 ff ff ff e8 d2 5d ee ff 48 83 c4 20 90 <0f> 0b e8 c6 8f 69 01 48 83 7d a0 00 0f 84 6a ff ff ff 48 8b 7d c0
RSP: 0018:ffff88801f8cf0e8 EFLAGS: 00010286
RAX: 0000000000000085 RBX: ffff88811718cda0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffff88801f8cf1a0 R08: ffffea000000000f R09: 0000000000000000
R10: ffff888237c7e028 R11: ffff88823f278d40 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f26537fe6c0(0000) GS:ffff8881aaf8d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2654574620 CR3: 0000000049ab8000 CR4: 00000000003526f0


Tested on:

commit:         4a0c9b33 Merge tag 'probes-fixes-v6.18-rc4' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17a79084580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2901a6a99b67fbcc
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=107a332f980000

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: uninit-value in tipc_rcv

tipc: Started in network mode
tipc: Node identity a287e0d4fc68, cluster identity 4711
tipc: tipc_buf_acquire data len: 0
tipc: Enabled bearer <eth:syzkaller0>, priority 0
=====================================================
BUG: KMSAN: uninit-value in tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_l2_rcv_msg+0x213/0x320 net/tipc/bearer.c:668
 __netif_receive_skb_list_ptype net/core/dev.c:6127 [inline]
 __netif_receive_skb_list_core+0x133e/0x16b0 net/core/dev.c:6169
 __netif_receive_skb_list net/core/dev.c:6221 [inline]
 netif_receive_skb_list_internal+0xee7/0x1530 net/core/dev.c:6312
 gro_normal_list include/net/gro.h:524 [inline]
 gro_flush_normal include/net/gro.h:532 [inline]
 napi_complete_done+0x3fb/0x7d0 net/core/dev.c:6681
 napi_complete include/linux/netdevice.h:589 [inline]
 tun_get_user+0x5953/0x6d70 drivers/net/tun.c:1924
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
 do_iter_readv_writev+0x9e1/0xc20 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 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:4977 [inline]
 slab_alloc_node mm/slub.c:5280 [inline]
 kmem_cache_alloc_node_noprof+0x989/0x16b0 mm/slub.c:5332
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 napi_alloc_skb+0xc1/0x740 net/core/skbuff.c:812
 napi_get_frags+0xab/0x250 net/core/gro.c:681
 tun_napi_alloc_frags drivers/net/tun.c:1404 [inline]
 tun_get_user+0x1352/0x6d70 drivers/net/tun.c:1784
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
 do_iter_readv_writev+0x9e1/0xc20 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 6569 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
=====================================================


Tested on:

commit:         4a0c9b33 Merge tag 'probes-fixes-v6.18-rc4' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1365ca92580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2901a6a99b67fbcc
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=13631114580000

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in tipc_buf_acquire

tipc: Started in network mode
tipc: Node identity d24fb5aaf302, cluster identity 4711
skbuff: skb_over_panic: text:ffffffff8fe5599a len:376 put:300 head:ffff88811965d340 data:ffff88811965d410 tail:0x248 end:0x180 dev:<NULL>
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:212!
Oops: invalid opcode: 0000 [#1] SMP PTI
CPU: 1 UID: 0 PID: 6630 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:skb_panic+0x2d3/0x340 net/core/skbuff.c:212
Code: d0 44 8b 45 cc 4c 8b 8d 58 ff ff ff 41 52 ff b5 70 ff ff ff ff b5 68 ff ff ff ff b5 60 ff ff ff e8 b2 5e ee ff 48 83 c4 20 90 <0f> 0b e8 56 88 69 01 48 83 7d a0 00 0f 84 6a ff ff ff 48 8b 7d c0
RSP: 0018:ffff888045ee30d0 EFLAGS: 00010282
RAX: 0000000000000089 RBX: ffff888118a30ba0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffff888045ee3188 R08: ffffea000000000f R09: 0000000000000000
R10: ffff888237c7f028 R11: ffff88823f277d80 R12: 000000000734019a
R13: 000000000734019a R14: 0000000000000000 R15: 0000000000000000
FS:  00007f60ea3b56c0(0000) GS:ffff8881ab08c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002280 CR3: 000000004a6b6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 skb_over_panic net/core/skbuff.c:217 [inline]
 skb_put+0x1f5/0x250 net/core/skbuff.c:2583
 skb_put_zero include/linux/skbuff.h:2788 [inline]
 tipc_buf_acquire+0x16a/0x280 net/tipc/msg.c:76
 tipc_disc_create+0x12f/0x870 net/tipc/discover.c:359
 tipc_enable_bearer net/tipc/bearer.c:348 [inline]
 __tipc_nl_bearer_enable+0x1f61/0x2a00 net/tipc/bearer.c:1047
 __tipc_nl_compat_doit net/tipc/netlink_compat.c:371 [inline]
 tipc_nl_compat_doit+0x67b/0xa10 net/tipc/netlink_compat.c:393
 tipc_nl_compat_handle net/tipc/netlink_compat.c:-1 [inline]
 tipc_nl_compat_recv+0x1007/0x1670 net/tipc/netlink_compat.c:1321
 genl_family_rcv_msg_doit+0x338/0x3f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0xacf/0xc10 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2552
 genl_rcv+0x41/0x60 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0xf04/0x12b0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2630
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2684
 __sys_sendmsg net/socket.c:2716 [inline]
 __do_sys_sendmsg net/socket.c:2721 [inline]
 __se_sys_sendmsg net/socket.c:2719 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2719
 x64_sys_call+0x1dfd/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f60e958eb69
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f60ea3b5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f60e97b6080 RCX: 00007f60e958eb69
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000006
RBP: 00007f60e9611df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f60e97b6080 R15: 00007fffe206b658
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:skb_panic+0x2d3/0x340 net/core/skbuff.c:212
Code: d0 44 8b 45 cc 4c 8b 8d 58 ff ff ff 41 52 ff b5 70 ff ff ff ff b5 68 ff ff ff ff b5 60 ff ff ff e8 b2 5e ee ff 48 83 c4 20 90 <0f> 0b e8 56 88 69 01 48 83 7d a0 00 0f 84 6a ff ff ff 48 8b 7d c0
RSP: 0018:ffff888045ee30d0 EFLAGS: 00010282
RAX: 0000000000000089 RBX: ffff888118a30ba0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffff888045ee3188 R08: ffffea000000000f R09: 0000000000000000
R10: ffff888237c7f028 R11: ffff88823f277d80 R12: 000000000734019a
R13: 000000000734019a R14: 0000000000000000 R15: 0000000000000000
FS:  00007f60ea3b56c0(0000) GS:ffff8881ab08c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002280 CR3: 000000004a6b6000 CR4: 00000000003526f0


Tested on:

commit:         e7c375b1 Merge tag 'vfs-6.18-rc7.fixes' of gitolite.ke..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15607884580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dab646ad75fa9d4a
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=17fa2fcd980000

Re: [syzbot] [tipc?] KMSAN: uninit-value in tipc_rcv (2)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KMSAN: uninit-value in tipc_rcv

=====================================================
BUG: KMSAN: uninit-value in tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_rcv+0x17fa/0x1ea0 net/tipc/node.c:2132
 tipc_l2_rcv_msg+0x213/0x320 net/tipc/bearer.c:668
 __netif_receive_skb_list_ptype net/core/dev.c:6127 [inline]
 __netif_receive_skb_list_core+0x133e/0x16b0 net/core/dev.c:6169
 __netif_receive_skb_list net/core/dev.c:6221 [inline]
 netif_receive_skb_list_internal+0xee7/0x1530 net/core/dev.c:6312
 gro_normal_list include/net/gro.h:524 [inline]
 gro_flush_normal include/net/gro.h:532 [inline]
 napi_complete_done+0x3fb/0x7d0 net/core/dev.c:6681
 napi_complete include/linux/netdevice.h:589 [inline]
 tun_get_user+0x5953/0x6d70 drivers/net/tun.c:1924
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
 do_iter_readv_writev+0x9e1/0xc20 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 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:4985 [inline]
 slab_alloc_node mm/slub.c:5288 [inline]
 kmem_cache_alloc_node_noprof+0x989/0x16b0 mm/slub.c:5340
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 napi_alloc_skb+0xc1/0x740 net/core/skbuff.c:812
 napi_get_frags+0xab/0x250 net/core/gro.c:681
 tun_napi_alloc_frags drivers/net/tun.c:1404 [inline]
 tun_get_user+0x1352/0x6d70 drivers/net/tun.c:1784
 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
 do_iter_readv_writev+0x9e1/0xc20 fs/read_write.c:-1
 vfs_writev+0x52a/0x1500 fs/read_write.c:1057
 do_writev+0x1b5/0x580 fs/read_write.c:1103
 __do_sys_writev fs/read_write.c:1171 [inline]
 __se_sys_writev fs/read_write.c:1168 [inline]
 __x64_sys_writev+0x99/0xf0 fs/read_write.c:1168
 x64_sys_call+0x24b1/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 6539 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
=====================================================


Tested on:

commit:         2eba5e05 Merge tag 'loongarch-fixes-6.18-2' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10bbb742580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dab646ad75fa9d4a
dashboard link: https://syzkaller.appspot.com/bug?extid=9a4fbb77c9d4aacd3388
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=16d74c2a580000