The syzbot fuzzer found a general protection fault in the HID subsystem: kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN CPU: 0 PID: 3715 Comm: syz-executor.3 Not tainted 5.2.0-rc6+ #15 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__pm_runtime_resume+0x49/0x180 drivers/base/power/runtime.c:1069 Code: ed 74 d5 fe 45 85 ed 0f 85 9a 00 00 00 e8 6f 73 d5 fe 48 8d bd c1 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 fe 00 00 00 RSP: 0018:ffff8881d99d78e0 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000020 RCX: ffffc90003f3f000 RDX: 0000000416d8686d RSI: ffffffff82676841 RDI: 00000020b6c3436a RBP: 00000020b6c340a9 R08: ffff8881c6d64800 R09: fffffbfff0e84c25 R10: ffff8881d99d7940 R11: ffffffff87426127 R12: 0000000000000004 R13: 0000000000000000 R14: ffff8881d9b94000 R15: ffffffff897f9048 FS: 00007f047f542700(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30f21000 CR3: 00000001ca032000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pm_runtime_get_sync include/linux/pm_runtime.h:226 [inline] usb_autopm_get_interface+0x1b/0x50 drivers/usb/core/driver.c:1707 usbhid_power+0x7c/0xe0 drivers/hid/usbhid/hid-core.c:1234 hid_hw_power include/linux/hid.h:1038 [inline] hidraw_open+0x20d/0x740 drivers/hid/hidraw.c:282 chrdev_open+0x219/0x5c0 fs/char_dev.c:413 do_dentry_open+0x497/0x1040 fs/open.c:778 do_last fs/namei.c:3416 [inline] path_openat+0x1430/0x3ff0 fs/namei.c:3533 do_filp_open+0x1a1/0x280 fs/namei.c:3563 do_sys_open+0x3c0/0x580 fs/open.c:1070 do_syscall_64+0xb7/0x560 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe It turns out the fault was caused by a bug in the HID Logitech driver, which violates the requirement that every pathway calling hid_hw_start() must also call hid_hw_stop(). This patch fixes the bug by making sure the requirement is met. Reported-and-tested-by: syzbot+3cbe5cd105d2ad56a1df@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> CC: <stable@xxxxxxxxxxxxxxx> --- [as1909] drivers/hid/hid-lg.c | 10 ++++++---- drivers/hid/hid-lg4ff.c | 1 - 2 files changed, 6 insertions(+), 5 deletions(-) Index: usb-devel/drivers/hid/hid-lg.c =================================================================== --- usb-devel.orig/drivers/hid/hid-lg.c +++ usb-devel/drivers/hid/hid-lg.c @@ -818,7 +818,7 @@ static int lg_probe(struct hid_device *h if (!buf) { ret = -ENOMEM; - goto err_free; + goto err_stop; } ret = hid_hw_raw_request(hdev, buf[0], buf, sizeof(cbuf), @@ -850,9 +850,12 @@ static int lg_probe(struct hid_device *h ret = lg4ff_init(hdev); if (ret) - goto err_free; + goto err_stop; return 0; + +err_stop: + hid_hw_stop(hdev); err_free: kfree(drv_data); return ret; @@ -863,8 +866,7 @@ static void lg_remove(struct hid_device struct lg_drv_data *drv_data = hid_get_drvdata(hdev); if (drv_data->quirks & LG_FF4) lg4ff_deinit(hdev); - else - hid_hw_stop(hdev); + hid_hw_stop(hdev); kfree(drv_data); } Index: usb-devel/drivers/hid/hid-lg4ff.c =================================================================== --- usb-devel.orig/drivers/hid/hid-lg4ff.c +++ usb-devel/drivers/hid/hid-lg4ff.c @@ -1477,7 +1477,6 @@ int lg4ff_deinit(struct hid_device *hid) } } #endif - hid_hw_stop(hid); drv_data->device_props = NULL; kfree(entry);