[syzbot] [usb?] memory leak in class_create

From: syzbot
Date: Mon May 01 2023 - 12:54:00 EST


Hello,

syzbot found the following issue on:

HEAD commit: 22b8cc3e78f5 Merge tag 'x86_mm_for_6.4' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16fc7958280000
kernel config: https://syzkaller.appspot.com/x/.config?x=5046ebeca744dd40
dashboard link: https://syzkaller.appspot.com/bug?extid=e7afd76ad060fa0d2605
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1599a2b4280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14eb395fc80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3ad2088c196b/disk-22b8cc3e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/61919a5b89c6/vmlinux-22b8cc3e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a7adb5503ac8/bzImage-22b8cc3e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e7afd76ad060fa0d2605@xxxxxxxxxxxxxxxxxxxxxxxxx

BUG: memory leak
unreferenced object 0xffff88810af67080 (size 96):
comm "kworker/0:2", pid 4402, jiffies 4294950769 (age 14.190s)
hex dump (first 32 bytes):
bf 03 9b 85 ff ff ff ff 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff81544e14>] kmalloc_trace+0x24/0x90 mm/slab_common.c:1057
[<ffffffff82b65445>] kmalloc include/linux/slab.h:559 [inline]
[<ffffffff82b65445>] kzalloc include/linux/slab.h:680 [inline]
[<ffffffff82b65445>] class_create+0x25/0x90 drivers/base/class.c:261
[<ffffffff831f7a80>] init_usb_class drivers/usb/core/file.c:91 [inline]
[<ffffffff831f7a80>] usb_register_dev+0x290/0x3d0 drivers/usb/core/file.c:179
[<ffffffff832cffc4>] usblp_probe+0x4e4/0x750 drivers/usb/class/usblp.c:1208
[<ffffffff831f39a9>] usb_probe_interface+0x179/0x3c0 drivers/usb/core/driver.c:396
[<ffffffff82b62d7d>] call_driver_probe drivers/base/dd.c:579 [inline]
[<ffffffff82b62d7d>] really_probe+0x12d/0x430 drivers/base/dd.c:658
[<ffffffff82b63141>] __driver_probe_device+0xc1/0x1a0 drivers/base/dd.c:800
[<ffffffff82b6324a>] driver_probe_device+0x2a/0x120 drivers/base/dd.c:830
[<ffffffff82b6343b>] __device_attach_driver+0xfb/0x150 drivers/base/dd.c:958
[<ffffffff82b60191>] bus_for_each_drv+0xc1/0x110 drivers/base/bus.c:457
[<ffffffff82b63962>] __device_attach+0x102/0x2a0 drivers/base/dd.c:1030
[<ffffffff82b618fa>] bus_probe_device+0xca/0xd0 drivers/base/bus.c:532
[<ffffffff82b5def3>] device_add+0x993/0xc60 drivers/base/core.c:3625
[<ffffffff831f0a89>] usb_set_configuration+0x9a9/0xc90 drivers/usb/core/message.c:2211
[<ffffffff832033a1>] usb_generic_driver_probe+0xa1/0x100 drivers/usb/core/generic.c:238
[<ffffffff831f3080>] usb_probe_device+0x60/0x140 drivers/usb/core/driver.c:293

BUG: memory leak
unreferenced object 0xffff8881051f1a00 (size 512):
comm "kworker/0:2", pid 4402, jiffies 4294950769 (age 14.190s)
hex dump (first 32 bytes):
00 1a 1f 05 81 88 ff ff 00 1a 1f 05 81 88 ff ff ................
00 00 00 00 00 00 00 00 bf 03 9b 85 ff ff ff ff ................
backtrace:
[<ffffffff81544e14>] kmalloc_trace+0x24/0x90 mm/slab_common.c:1057
[<ffffffff82b65308>] kmalloc include/linux/slab.h:559 [inline]
[<ffffffff82b65308>] kzalloc include/linux/slab.h:680 [inline]
[<ffffffff82b65308>] class_register+0x28/0x140 drivers/base/class.c:186
[<ffffffff82b65467>] class_create+0x47/0x90 drivers/base/class.c:270
[<ffffffff831f7a80>] init_usb_class drivers/usb/core/file.c:91 [inline]
[<ffffffff831f7a80>] usb_register_dev+0x290/0x3d0 drivers/usb/core/file.c:179
[<ffffffff832cffc4>] usblp_probe+0x4e4/0x750 drivers/usb/class/usblp.c:1208
[<ffffffff831f39a9>] usb_probe_interface+0x179/0x3c0 drivers/usb/core/driver.c:396
[<ffffffff82b62d7d>] call_driver_probe drivers/base/dd.c:579 [inline]
[<ffffffff82b62d7d>] really_probe+0x12d/0x430 drivers/base/dd.c:658
[<ffffffff82b63141>] __driver_probe_device+0xc1/0x1a0 drivers/base/dd.c:800
[<ffffffff82b6324a>] driver_probe_device+0x2a/0x120 drivers/base/dd.c:830
[<ffffffff82b6343b>] __device_attach_driver+0xfb/0x150 drivers/base/dd.c:958
[<ffffffff82b60191>] bus_for_each_drv+0xc1/0x110 drivers/base/bus.c:457
[<ffffffff82b63962>] __device_attach+0x102/0x2a0 drivers/base/dd.c:1030
[<ffffffff82b618fa>] bus_probe_device+0xca/0xd0 drivers/base/bus.c:532
[<ffffffff82b5def3>] device_add+0x993/0xc60 drivers/base/core.c:3625
[<ffffffff831f0a89>] usb_set_configuration+0x9a9/0xc90 drivers/usb/core/message.c:2211
[<ffffffff832033a1>] usb_generic_driver_probe+0xa1/0x100 drivers/usb/core/generic.c:238



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