Hello, syzbot found the following issue on: HEAD commit: 614da38e2f7a Merge tag 'hid-for-linus-2024051401' of git:/.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=1315203c980000 kernel config: https://syzkaller.appspot.com/x/.config?x=f5d2cbf33633f507 dashboard link: https://syzkaller.appspot.com/bug?extid=ec0723ba9605678b14bf 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=14b284e8980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1653d768980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/89eafb874b71/disk-614da38e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/356000512ad9/vmlinux-614da38e.xz kernel image: https://storage.googleapis.com/syzbot-assets/839c73939115/bzImage-614da38e.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ec0723ba9605678b14bf@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: uninit-value in ppp_async_encode drivers/net/ppp/ppp_async.c:548 [inline] BUG: KMSAN: uninit-value in ppp_async_push+0xc05/0x2660 drivers/net/ppp/ppp_async.c:675 ppp_async_encode drivers/net/ppp/ppp_async.c:548 [inline] ppp_async_push+0xc05/0x2660 drivers/net/ppp/ppp_async.c:675 ppp_async_send+0x130/0x1b0 drivers/net/ppp/ppp_async.c:634 ppp_push+0x220/0x22b0 drivers/net/ppp/ppp_generic.c:1883 ppp_send_frame drivers/net/ppp/ppp_generic.c:1846 [inline] __ppp_xmit_process+0x123a/0x2780 drivers/net/ppp/ppp_generic.c:1646 ppp_xmit_process+0x100/0x2b0 drivers/net/ppp/ppp_generic.c:1667 ppp_write+0x63a/0x7d0 drivers/net/ppp/ppp_generic.c:521 do_loop_readv_writev fs/read_write.c:764 [inline] vfs_writev+0xb0e/0x1450 fs/read_write.c:973 do_pwritev fs/read_write.c:1072 [inline] __do_sys_pwritev fs/read_write.c:1119 [inline] __se_sys_pwritev fs/read_write.c:1114 [inline] __x64_sys_pwritev+0x2e5/0x500 fs/read_write.c:1114 x64_sys_call+0x3539/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:297 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/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:3877 [inline] slab_alloc_node mm/slub.c:3918 [inline] kmem_cache_alloc_node+0x622/0xc90 mm/slub.c:3961 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1319 [inline] ppp_write+0xe5/0x7d0 drivers/net/ppp/ppp_generic.c:509 do_loop_readv_writev fs/read_write.c:764 [inline] vfs_writev+0xb0e/0x1450 fs/read_write.c:973 do_pwritev fs/read_write.c:1072 [inline] __do_sys_pwritev fs/read_write.c:1119 [inline] __se_sys_pwritev fs/read_write.c:1114 [inline] __x64_sys_pwritev+0x2e5/0x500 fs/read_write.c:1114 x64_sys_call+0x3539/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:297 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 1 PID: 5049 Comm: syz-executor420 Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 ===================================================== --- 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
