Hello, syzbot found the following issue on: HEAD commit: d7a5aa4b3c00 Merge tag 'perf-tools-fixes-for-v6.11-2024-08.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10dadbf3980000 kernel config: https://syzkaller.appspot.com/x/.config?x=836be0e882e376f7 dashboard link: https://syzkaller.appspot.com/bug?extid=9760fbbd535cee131f81 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/946f8425a0a3/disk-d7a5aa4b.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6ee98ed4e4f2/vmlinux-d7a5aa4b.xz kernel image: https://storage.googleapis.com/syzbot-assets/944481feb386/bzImage-d7a5aa4b.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9760fbbd535cee131f81@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline] BUG: KMSAN: kernel-infoleak in _inline_copy_to_user include/linux/uaccess.h:180 [inline] BUG: KMSAN: kernel-infoleak in _copy_to_user+0xbc/0x110 lib/usercopy.c:26 instrument_copy_to_user include/linux/instrumented.h:114 [inline] _inline_copy_to_user include/linux/uaccess.h:180 [inline] _copy_to_user+0xbc/0x110 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:209 [inline] wdm_read+0x227/0x1270 drivers/usb/class/cdc-wdm.c:603 vfs_read+0x2a1/0xf60 fs/read_write.c:474 ksys_read+0x20f/0x4c0 fs/read_write.c:619 __do_sys_read fs/read_write.c:629 [inline] __se_sys_read fs/read_write.c:627 [inline] __x64_sys_read+0x93/0xe0 fs/read_write.c:627 x64_sys_call+0x3055/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:1 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:3994 [inline] slab_alloc_node mm/slub.c:4037 [inline] __do_kmalloc_node mm/slub.c:4157 [inline] __kmalloc_noprof+0x661/0xf30 mm/slub.c:4170 kmalloc_noprof include/linux/slab.h:685 [inline] wdm_create+0xf5a/0x2240 drivers/usb/class/cdc-wdm.c:1066 wdm_probe+0x265/0x330 drivers/usb/class/cdc-wdm.c:1165 usb_probe_interface+0xd6f/0x1350 drivers/usb/core/driver.c:399 really_probe+0x4db/0xd90 drivers/base/dd.c:657 __driver_probe_device+0x2ab/0x5d0 drivers/base/dd.c:799 driver_probe_device+0x72/0x890 drivers/base/dd.c:829 __device_attach_driver+0x568/0x9e0 drivers/base/dd.c:957 bus_for_each_drv+0x403/0x620 drivers/base/bus.c:457 __device_attach+0x3c1/0x650 drivers/base/dd.c:1029 device_initial_probe+0x32/0x40 drivers/base/dd.c:1078 bus_probe_device+0x3dc/0x5c0 drivers/base/bus.c:532 device_add+0x13aa/0x1ba0 drivers/base/core.c:3682 usb_set_configuration+0x31c9/0x38d0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x109/0x2a0 drivers/usb/core/generic.c:254 usb_probe_device+0x3a7/0x690 drivers/usb/core/driver.c:294 really_probe+0x4db/0xd90 drivers/base/dd.c:657 __driver_probe_device+0x2ab/0x5d0 drivers/base/dd.c:799 driver_probe_device+0x72/0x890 drivers/base/dd.c:829 __device_attach_driver+0x568/0x9e0 drivers/base/dd.c:957 bus_for_each_drv+0x403/0x620 drivers/base/bus.c:457 __device_attach+0x3c1/0x650 drivers/base/dd.c:1029 device_initial_probe+0x32/0x40 drivers/base/dd.c:1078 bus_probe_device+0x3dc/0x5c0 drivers/base/bus.c:532 device_add+0x13aa/0x1ba0 drivers/base/core.c:3682 usb_new_device+0x15f4/0x2470 drivers/usb/core/hub.c:2651 hub_port_connect drivers/usb/core/hub.c:5521 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x4ffb/0x72d0 drivers/usb/core/hub.c:5903 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3312 worker_thread+0xea5/0x1520 kernel/workqueue.c:3390 kthread+0x3dd/0x540 kernel/kthread.c:389 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Byte 0 of 1 is uninitialized Memory access of size 1 starts at ffff88803f011400 Data copied to user address 0000000020000280 CPU: 1 UID: 0 PID: 7440 Comm: syz.1.721 Not tainted 6.11.0-rc3-syzkaller-00156-gd7a5aa4b3c00 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 ===================================================== --- 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 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
