Hello, syzbot found the following issue on: HEAD commit: 1868f9d0260e Merge tag 'for-linux-6.12-ofs1' of git://git... git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=13730e07980000 kernel config: https://syzkaller.appspot.com/x/.config?x=acaa65be5f19fc5a dashboard link: https://syzkaller.appspot.com/bug?extid=1d121645899e7692f92a 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=127f8080580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14b86c27980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/51af83d2907b/disk-1868f9d0.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/4cd235c942a6/vmlinux-1868f9d0.xz kernel image: https://storage.googleapis.com/syzbot-assets/a321106ef897/bzImage-1868f9d0.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1d121645899e7692f92a@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: uninit-value in ppp_async_encode drivers/net/ppp/ppp_async.c:545 [inline] BUG: KMSAN: uninit-value in ppp_async_push+0xb4f/0x2660 drivers/net/ppp/ppp_async.c:675 ppp_async_encode drivers/net/ppp/ppp_async.c:545 [inline] ppp_async_push+0xb4f/0x2660 drivers/net/ppp/ppp_async.c:675 ppp_async_send+0x130/0x1b0 drivers/net/ppp/ppp_async.c:634 ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2280 [inline] ppp_input+0x1f1/0xe60 drivers/net/ppp/ppp_generic.c:2304 pppoe_rcv_core+0x1d3/0x720 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1113 __release_sock+0x1da/0x330 net/core/sock.c:3072 release_sock+0x6b/0x250 net/core/sock.c:3626 pppoe_sendmsg+0x2b8/0xb90 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:745 ____sys_sendmsg+0x903/0xb60 net/socket.c:2603 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2657 __sys_sendmmsg+0x3be/0x950 net/socket.c:2743 __do_sys_sendmmsg net/socket.c:2772 [inline] __se_sys_sendmmsg net/socket.c:2769 [inline] __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2769 x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4092 [inline] slab_alloc_node mm/slub.c:4135 [inline] kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4187 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:587 __alloc_skb+0x363/0x7b0 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1322 [inline] sock_wmalloc+0xfe/0x1a0 net/core/sock.c:2732 pppoe_sendmsg+0x3a7/0xb90 drivers/net/ppp/pppoe.c:867 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:745 ____sys_sendmsg+0x903/0xb60 net/socket.c:2603 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2657 __sys_sendmmsg+0x3be/0x950 net/socket.c:2743 __do_sys_sendmmsg net/socket.c:2772 [inline] __se_sys_sendmmsg net/socket.c:2769 [inline] __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2769 x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 1 UID: 0 PID: 5200 Comm: syz-executor848 Not tainted 6.11.0-syzkaller-07462-g1868f9d0260e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 ===================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title 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. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
