Hello, syzbot found the following issue on: HEAD commit: a68a0262 mm/madvise: remove racy mm ownership check git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1538046b500000 kernel config: https://syzkaller.appspot.com/x/.config?x=4305fa9ea70c7a9f dashboard link: https://syzkaller.appspot.com/bug?extid=c9e365d7f450e8aa615d compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1779cc13500000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1173d00f500000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c9e365d7f450e8aa615d@xxxxxxxxxxxxxxxxxxxxxxxxx BUG: memory leak unreferenced object 0xffff88810adde100 (size 32): comm "kworker/1:0", pid 17, jiffies 4294947788 (age 19.520s) hex dump (first 32 bytes): 10 30 c3 0d 81 88 ff ff c0 fa 63 12 81 88 ff ff .0........c..... 00 30 c3 0d 81 88 ff ff 80 d1 3a 08 81 88 ff ff .0........:..... backtrace: [<0000000019512953>] kmalloc include/linux/slab.h:552 [inline] [<0000000019512953>] kzalloc include/linux/slab.h:664 [inline] [<0000000019512953>] dlfb_alloc_urb_list drivers/video/fbdev/udlfb.c:1892 [inline] [<0000000019512953>] dlfb_usb_probe.cold+0x289/0x988 drivers/video/fbdev/udlfb.c:1704 [<0000000072160152>] usb_probe_interface+0x177/0x370 drivers/usb/core/driver.c:396 [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554 [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738 [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844 [<00000000de0a5a5c>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431 [<00000000463fbcb4>] __device_attach+0x122/0x250 drivers/base/dd.c:912 [<00000000b881a711>] bus_probe_device+0xc6/0xe0 drivers/base/bus.c:491 [<00000000364bbda5>] device_add+0x5ac/0xc30 drivers/base/core.c:2936 [<00000000eecca418>] usb_set_configuration+0x9de/0xb90 drivers/usb/core/message.c:2159 [<00000000edfeca2d>] usb_generic_driver_probe+0x8c/0xc0 drivers/usb/core/generic.c:238 [<000000001830872b>] usb_probe_device+0x5c/0x140 drivers/usb/core/driver.c:293 [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554 [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738 [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844 [<00000000de0a5a5c>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431 BUG: memory leak unreferenced object 0xffff8881083ad180 (size 192): comm "kworker/1:0", pid 17, jiffies 4294947788 (age 19.520s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 98 d1 3a 08 81 88 ff ff ..........:..... backtrace: [<00000000a7783a78>] kmalloc include/linux/slab.h:557 [inline] [<00000000a7783a78>] usb_alloc_urb+0x66/0xe0 drivers/usb/core/urb.c:74 [<0000000082822843>] dlfb_alloc_urb_list drivers/video/fbdev/udlfb.c:1897 [inline] [<0000000082822843>] dlfb_usb_probe.cold+0x2aa/0x988 drivers/video/fbdev/udlfb.c:1704 [<0000000072160152>] usb_probe_interface+0x177/0x370 drivers/usb/core/driver.c:396 [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554 [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738 [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844 [<00000000de0a5a5c>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431 [<00000000463fbcb4>] __device_attach+0x122/0x250 drivers/base/dd.c:912 [<00000000b881a711>] bus_probe_device+0xc6/0xe0 drivers/base/bus.c:491 [<00000000364bbda5>] device_add+0x5ac/0xc30 drivers/base/core.c:2936 [<00000000eecca418>] usb_set_configuration+0x9de/0xb90 drivers/usb/core/message.c:2159 [<00000000edfeca2d>] usb_generic_driver_probe+0x8c/0xc0 drivers/usb/core/generic.c:238 [<000000001830872b>] usb_probe_device+0x5c/0x140 drivers/usb/core/driver.c:293 [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554 [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738 [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844 BUG: memory leak unreferenced object 0xffff88811263fb20 (size 32): comm "kworker/1:0", pid 17, jiffies 4294947788 (age 19.530s) hex dump (first 32 bytes): 00 fb 63 12 81 88 ff ff 10 30 c3 0d 81 88 ff ff ..c......0...... 00 30 c3 0d 81 88 ff ff c0 53 c8 0b 81 88 ff ff .0.......S...... backtrace: [<0000000019512953>] kmalloc include/linux/slab.h:552 [inline] [<0000000019512953>] kzalloc include/linux/slab.h:664 [inline] [<0000000019512953>] dlfb_alloc_urb_list drivers/video/fbdev/udlfb.c:1892 [inline] [<0000000019512953>] dlfb_usb_probe.cold+0x289/0x988 drivers/video/fbdev/udlfb.c:1704 [<0000000072160152>] usb_probe_interface+0x177/0x370 drivers/usb/core/driver.c:396 [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554 [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738 [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844 [<00000000de0a5a5c>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431 [<00000000463fbcb4>] __device_attach+0x122/0x250 drivers/base/dd.c:912 [<00000000b881a711>] bus_probe_device+0xc6/0xe0 drivers/base/bus.c:491 [<00000000364bbda5>] device_add+0x5ac/0xc30 drivers/base/core.c:2936 [<00000000eecca418>] usb_set_configuration+0x9de/0xb90 drivers/usb/core/message.c:2159 [<00000000edfeca2d>] usb_generic_driver_probe+0x8c/0xc0 drivers/usb/core/generic.c:238 [<000000001830872b>] usb_probe_device+0x5c/0x140 drivers/usb/core/driver.c:293 [<00000000a8d6726f>] really_probe+0x159/0x480 drivers/base/dd.c:554 [<00000000c3ce4b0e>] driver_probe_device+0x84/0x100 drivers/base/dd.c:738 [<00000000e942e01c>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:844 [<00000000de0a5a5c>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431 --- 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. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
