From: Peter Chen <peter.chen@xxxxxxx> [ Upstream commit 1a1c851bbd706ea9f3a9756c2d3db28523506d3b ] We meet several NULL pointer issues if configfs_composite_unbind and composite_setup (or composite_disconnect) are running together. These issues occur when do the function switch stress test, the configfs_compsoite_unbind is called from user mode by echo "" to /sys/../UDC entry, and meanwhile, the setup interrupt or disconnect interrupt occurs by hardware. The composite_setup will get the cdev from get_gadget_data, but configfs_composite_unbind will set gadget data as NULL, so the NULL pointer issue occurs. This concurrent is hard to reproduce by native kernel, but can be reproduced by android kernel. In this commit, we introduce one spinlock belongs to structure gadget_info since we can't use the same spinlock in usb_composite_dev due to exclusive running together between composite_setup and configfs_composite_unbind. And one bit flag 'unbind' to indicate the code is at unbind routine, this bit is needed due to we release the lock at during configfs_composite_unbind sometimes, and composite_setup may be run at that time. Several oops: oops 1: android_work: sent uevent USB_STATE=CONNECTED configfs-gadget gadget: super-speed config #1: b android_work: sent uevent USB_STATE=CONFIGURED init: Received control message 'start' for 'adbd' from pid: 3515 (system_server) Unable to handle kernel NULL pointer dereference at virtual address 0000002a init: Received control message 'stop' for 'adbd' from pid: 3375 (/vendor/bin/hw/android.hardware.usb@1.1-servic) Mem abort info: Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgd = ffff8008f1b7f000 [000000000000002a] *pgd=0000000000000000 Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 4 PID: 2457 Comm: irq/125-5b11000 Not tainted 4.14.98-07846-g0b40a9b-dirty #16 Hardware name: Freescale i.MX8QM MEK (DT) task: ffff8008f2a98000 task.stack: ffff00000b7b8000 PC is at composite_setup+0x44/0x1508 LR is at android_setup+0xb8/0x13c pc : [<ffff0000089ffb3c>] lr : [<ffff000008a032fc>] pstate: 800001c5 sp : ffff00000b7bbb80 x29: ffff00000b7bbb80 x28: ffff8008f2a3c010 x27: 0000000000000001 x26: 0000000000000000 [1232/1897] audit: audit_lost=25791 audit_rate_limit=5 audit_backlog_limit=64 x25: 00000000ffffffa1 x24: ffff8008f2a3c010 audit: rate limit exceeded x23: 0000000000000409 x22: ffff000009c8e000 x21: ffff8008f7a8b428 x20: ffff00000afae000 x19: ffff0000089ff000 x18: 0000000000000000 x17: 0000000000000000 x16: ffff0000082b7c9c x15: 0000000000000000 x14: f1866f5b952aca46 x13: e35502e30d44349c x12: 0000000000000008 x11: 0000000000000008 x10: 0000000000000a30 x9 : ffff00000b7bbd00 x8 : ffff8008f2a98a90 x7 : ffff8008f27a9c90 x6 : 0000000000000001 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000006 x1 : ffff0000089ff8d0 x0 : 732a010310b9ed00 X7: 0xffff8008f27a9c10: 9c10 00000002 00000000 00000001 00000000 13110000 ffff0000 00000002 00208040 9c30 00000000 00000000 00000000 00000000 00000000 00000005 00000029 00000000 9c50 00051778 00000001 f27a8e00 ffff8008 00000005 00000000 00000078 00000078 9c70 00000078 00000000 09031d48 ffff0000 00100000 00000000 00400000 00000000 9c90 00000001 00000000 00000000 00000000 00000000 00000000 ffefb1a0 ffff8008 9cb0 f27a9ca8 ffff8008 00000000 00000000 b9d88037 00000173 1618a3eb 00000001 9cd0 870a792a 0000002e 16188fe6 00000001 0000242b 00000000 00000000 00000000 using random self ethernet address 9cf0 019a4646 00000000 000547f3 00000000 ecfd6c33 00000002 00000000 using random host ethernet address 00000000 X8: 0xffff8008f2a98a10: 8a10 00000000 00000000 f7788d00 ffff8008 00000001 00000000 00000000 00000000 8a30 eb218000 ffff8008 f2a98000 ffff8008 f2a98000 ffff8008 09885000 ffff0000 8a50 f34df480 ffff8008 00000000 00000000 f2a98648 ffff8008 09c8e000 ffff0000 8a70 fff2c800 ffff8008 09031d48 ffff0000 0b7bbd00 ffff0000 0b7bbd00 ffff0000 8a90 080861bc ffff0000 00000000 00000000 00000000 00000000 00000000 00000000 8ab0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 8ad0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 8af0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 X21: 0xffff8008f7a8b3a8: b3a8 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 b3c8 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 b3e8 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 b408 00000000 00000000 00000000 00000000 00000000 00000000 00000001 00000000 b428 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 b448 0053004d 00540046 00300031 00010030 eb07b520 ffff8008 20011201 00000003 b468 e418d109 0104404e 00010302 00000000 eb07b558 ffff8008 eb07b558 ffff8008 b488 f7a8b488 ffff8008 f7a8b488 ffff8008 f7a8b300 ffff8008 00000000 00000000 X24: 0xffff8008f2a3bf90: bf90 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bfb0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bfd0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bff0 00000000 00000000 00000000 00000000 f76c8010 ffff8008 f76c8010 ffff8008 c010 00000000 00000000 f2a3c018 ffff8008 f2a3c018 ffff8008 08a067dc ffff0000 c030 f2a5a000 ffff8008 091c3650 ffff0000 f716fd18 ffff8008 f716fe30 ffff8008 c050 f2ce4a30 ffff8008 00000000 00000005 00000000 00000000 095d1568 ffff0000 c070 f76c8010 ffff8008 f2ce4b00 ffff8008 095cac68 ffff0000 f2a5a028 ffff8008 X28: 0xffff8008f2a3bf90: bf90 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bfb0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bfd0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bff0 00000000 00000000 00000000 00000000 f76c8010 ffff8008 f76c8010 ffff8008 c010 00000000 00000000 f2a3c018 ffff8008 f2a3c018 ffff8008 08a067dc ffff0000 c030 f2a5a000 ffff8008 091c3650 ffff0000 f716fd18 ffff8008 f716fe30 ffff8008 c050 f2ce4a30 ffff8008 00000000 00000005 00000000 00000000 095d1568 ffff0000 c070 f76c8010 ffff8008 f2ce4b00 ffff8008 095cac68 ffff0000 f2a5a028 ffff8008 Process irq/125-5b11000 (pid: 2457, stack limit = 0xffff00000b7b8000) Call trace: Exception stack(0xffff00000b7bba40 to 0xffff00000b7bbb80) ba40: 732a010310b9ed00 ffff0000089ff8d0 0000000000000006 0000000000000000 ba60: 0000000000000001 0000000000000000 0000000000000001 ffff8008f27a9c90 ba80: ffff8008f2a98a90 ffff00000b7bbd00 0000000000000a30 0000000000000008 baa0: 0000000000000008 e35502e30d44349c f1866f5b952aca46 0000000000000000 bac0: ffff0000082b7c9c 0000000000000000 0000000000000000 ffff0000089ff000 bae0: ffff00000afae000 ffff8008f7a8b428 ffff000009c8e000 0000000000000409 bb00: ffff8008f2a3c010 00000000ffffffa1 0000000000000000 0000000000000001 bb20: ffff8008f2a3c010 ffff00000b7bbb80 ffff000008a032fc ffff00000b7bbb80 bb40: ffff0000089ffb3c 00000000800001c5 ffff00000b7bbb80 732a010310b9ed00 bb60: ffffffffffffffff ffff0000080f777c ffff00000b7bbb80 ffff0000089ffb3c [<ffff0000089ffb3c>] composite_setup+0x44/0x1508 [<ffff000008a032fc>] android_setup+0xb8/0x13c [<ffff0000089bd9a8>] cdns3_ep0_delegate_req+0x44/0x70 [<ffff0000089bdff4>] cdns3_check_ep0_interrupt_proceed+0x33c/0x654 [<ffff0000089bca44>] cdns3_device_thread_irq_handler+0x4b0/0x4bc [<ffff0000089b77b4>] cdns3_thread_irq+0x48/0x68 [<ffff000008145bf0>] irq_thread_fn+0x28/0x88 [<ffff000008145e38>] irq_thread+0x13c/0x228 [<ffff0000080fed70>] kthread+0x104/0x130 [<ffff000008085064>] ret_from_fork+0x10/0x18 oops2: composite_disconnect: Calling disconnect on a Gadget that is not connected android_work: did not send uevent (0 0 (null)) init: Received control message 'stop' for 'adbd' from pid: 3359 (/vendor/bin/hw/android.hardware.usb@xxxxxxxxxxxxxxx) init: Sending signal 9 to service 'adbd' (pid 22343) process group... ------------[ cut here ]------------ audit: audit_lost=180038 audit_rate_limit=5 audit_backlog_limit=64 audit: rate limit exceeded WARNING: CPU: 0 PID: 3468 at kernel_imx/drivers/usb/gadget/composite.c:2009 composite_disconnect+0x80/0x88 Modules linked in: CPU: 0 PID: 3468 Comm: HWC-UEvent-Thre Not tainted 4.14.98-07846-g0b40a9b-dirty #16 Hardware name: Freescale i.MX8QM MEK (DT) task: ffff8008f2349c00 task.stack: ffff00000b0a8000 PC is at composite_disconnect+0x80/0x88 LR is at composite_disconnect+0x80/0x88 pc : [<ffff0000089ff9b0>] lr : [<ffff0000089ff9b0>] pstate: 600001c5 sp : ffff000008003dd0 x29: ffff000008003dd0 x28: ffff8008f2349c00 x27: ffff000009885018 x26: ffff000008004000 Timeout for IPC response! x25: ffff000009885018 x24: ffff000009c8e280 x23: ffff8008f2d98010 x22: 00000000000001c0 x21: ffff8008f2d98394 x20: ffff8008f2d98010 x19: 0000000000000000 x18: 0000e3956f4f075a fxos8700 4-001e: i2c block read acc failed x17: 0000e395735727e8 x16: ffff00000829f4d4 x15: ffffffffffffffff x14: 7463656e6e6f6320 x13: 746f6e2009090920 x12: 7369207461687420 x11: 7465676461472061 x10: 206e6f207463656e x9 : 6e6f637369642067 x8 : ffff000009c8e280 x7 : ffff0000086ca6cc x6 : ffff000009f15e78 x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffffffffffffffff x2 : c3f28b86000c3900 x1 : c3f28b86000c3900 x0 : 000000000000004e X20: 0xffff8008f2d97f90: 7f90 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7fb0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 libprocessgroup: Failed to kill process cgroup uid 0 pid 22343 in 215ms, 1 processes remain 7fd0 Timeout for IPC response! 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 using random self ethernet address 7ff0 00000000 00000000 00000000 00000000 f76c8010 ffff8008 f76c8010 ffff8008 8010 00000100 00000000 f2d98018 ffff8008 f2d98018 ffff8008 08a067dc using random host ethernet address ffff0000 8030 f206d800 ffff8008 091c3650 ffff0000 f7957b18 ffff8008 f7957730 ffff8008 8050 f716a630 ffff8008 00000000 00000005 00000000 00000000 095d1568 ffff0000 8070 f76c8010 ffff8008 f716a800 ffff8008 095cac68 ffff0000 f206d828 ffff8008 X21: 0xffff8008f2d98314: 8314 ffff8008 00000000 00000000 00000000 00000000 00000000 00000000 00000000 8334 00000000 00000000 00000000 00000000 00000000 08a04cf4 ffff0000 00000000 8354 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 8374 00000000 00000000 00000000 00001001 00000000 00000000 00000000 00000000 8394 e4bbe4bb 0f230000 ffff0000 0afae000 ffff0000 ae001000 00000000 f206d400 Timeout for IPC response! 83b4 ffff8008 00000000 00000000 f7957b18 ffff8008 f7957718 ffff8008 f7957018 83d4 ffff8008 f7957118 ffff8008 f7957618 ffff8008 f7957818 ffff8008 f7957918 83f4 ffff8008 f7957d18 ffff8008 00000000 00000000 00000000 00000000 00000000 X23: 0xffff8008f2d97f90: 7f90 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7fb0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7fd0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 7ff0 00000000 00000000 00000000 00000000 f76c8010 ffff8008 f76c8010 ffff8008 8010 00000100 00000000 f2d98018 ffff8008 f2d98018 ffff8008 08a067dc ffff0000 8030 f206d800 ffff8008 091c3650 ffff0000 f7957b18 ffff8008 f7957730 ffff8008 8050 f716a630 ffff8008 00000000 00000005 00000000 00000000 095d1568 ffff0000 8070 f76c8010 ffff8008 f716a800 ffff8008 095cac68 ffff0000 f206d828 ffff8008 X28: 0xffff8008f2349b80: 9b80 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9ba0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9bc0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9be0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9c00 00000022 00000000 ffffffff ffffffff 00010001 00000000 00000000 00000000 9c20 0b0a8000 ffff0000 00000002 00404040 00000000 00000000 00000000 00000000 9c40 00000001 00000000 00000001 00000000 001ebd44 00000001 f390b800 ffff8008 9c60 00000000 00000001 00000070 00000070 00000070 00000000 09031d48 ffff0000 Call trace: Exception stack(0xffff000008003c90 to 0xffff000008003dd0) 3c80: 000000000000004e c3f28b86000c3900 3ca0: c3f28b86000c3900 ffffffffffffffff 0000000000000000 0000000000000000 3cc0: ffff000009f15e78 ffff0000086ca6cc ffff000009c8e280 6e6f637369642067 3ce0: 206e6f207463656e 7465676461472061 7369207461687420 746f6e2009090920 3d00: 7463656e6e6f6320 ffffffffffffffff ffff00000829f4d4 0000e395735727e8 3d20: 0000e3956f4f075a 0000000000000000 ffff8008f2d98010 ffff8008f2d98394 3d40: 00000000000001c0 ffff8008f2d98010 ffff000009c8e280 ffff000009885018 3d60: ffff000008004000 ffff000009885018 ffff8008f2349c00 ffff000008003dd0 3d80: ffff0000089ff9b0 ffff000008003dd0 ffff0000089ff9b0 00000000600001c5 3da0: ffff8008f33f2cd8 0000000000000000 0000ffffffffffff 0000000000000000 init: Received control message 'start' for 'adbd' from pid: 3359 (/vendor/bin/hw/android.hardware.usb@xxxxxxxxxxxxxxx) 3dc0: ffff000008003dd0 ffff0000089ff9b0 [<ffff0000089ff9b0>] composite_disconnect+0x80/0x88 [<ffff000008a044d4>] android_disconnect+0x3c/0x68 [<ffff0000089ba9f8>] cdns3_device_irq_handler+0xfc/0x2c8 [<ffff0000089b84c0>] cdns3_irq+0x44/0x94 [<ffff00000814494c>] __handle_irq_event_percpu+0x60/0x24c [<ffff000008144c0c>] handle_irq_event+0x58/0xc0 [<ffff00000814873c>] handle_fasteoi_irq+0x98/0x180 [<ffff000008143a10>] generic_handle_irq+0x24/0x38 [<ffff000008144170>] __handle_domain_irq+0x60/0xac [<ffff0000080819c4>] gic_handle_irq+0xd4/0x17c Signed-off-by: Peter Chen <peter.chen@xxxxxxx> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/usb/gadget/configfs.c | 110 ++++++++++++++++++++++++++++++++-- 1 file changed, 105 insertions(+), 5 deletions(-) diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c index 0251299428946..33852c2b29d1a 100644 --- a/drivers/usb/gadget/configfs.c +++ b/drivers/usb/gadget/configfs.c @@ -61,6 +61,8 @@ struct gadget_info { bool use_os_desc; char b_vendor_code; char qw_sign[OS_STRING_QW_SIGN_LEN]; + spinlock_t spinlock; + bool unbind; }; static inline struct gadget_info *to_gadget_info(struct config_item *item) @@ -1244,6 +1246,7 @@ static int configfs_composite_bind(struct usb_gadget *gadget, int ret; /* the gi->lock is hold by the caller */ + gi->unbind = 0; cdev->gadget = gadget; set_gadget_data(gadget, cdev); ret = composite_dev_prepare(composite, cdev); @@ -1376,31 +1379,128 @@ static void configfs_composite_unbind(struct usb_gadget *gadget) { struct usb_composite_dev *cdev; struct gadget_info *gi; + unsigned long flags; /* the gi->lock is hold by the caller */ cdev = get_gadget_data(gadget); gi = container_of(cdev, struct gadget_info, cdev); + spin_lock_irqsave(&gi->spinlock, flags); + gi->unbind = 1; + spin_unlock_irqrestore(&gi->spinlock, flags); kfree(otg_desc[0]); otg_desc[0] = NULL; purge_configs_funcs(gi); composite_dev_cleanup(cdev); usb_ep_autoconfig_reset(cdev->gadget); + spin_lock_irqsave(&gi->spinlock, flags); cdev->gadget = NULL; set_gadget_data(gadget, NULL); + spin_unlock_irqrestore(&gi->spinlock, flags); +} + +static int configfs_composite_setup(struct usb_gadget *gadget, + const struct usb_ctrlrequest *ctrl) +{ + struct usb_composite_dev *cdev; + struct gadget_info *gi; + unsigned long flags; + int ret; + + cdev = get_gadget_data(gadget); + if (!cdev) + return 0; + + gi = container_of(cdev, struct gadget_info, cdev); + spin_lock_irqsave(&gi->spinlock, flags); + cdev = get_gadget_data(gadget); + if (!cdev || gi->unbind) { + spin_unlock_irqrestore(&gi->spinlock, flags); + return 0; + } + + ret = composite_setup(gadget, ctrl); + spin_unlock_irqrestore(&gi->spinlock, flags); + return ret; +} + +static void configfs_composite_disconnect(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev; + struct gadget_info *gi; + unsigned long flags; + + cdev = get_gadget_data(gadget); + if (!cdev) + return; + + gi = container_of(cdev, struct gadget_info, cdev); + spin_lock_irqsave(&gi->spinlock, flags); + cdev = get_gadget_data(gadget); + if (!cdev || gi->unbind) { + spin_unlock_irqrestore(&gi->spinlock, flags); + return; + } + + composite_disconnect(gadget); + spin_unlock_irqrestore(&gi->spinlock, flags); +} + +static void configfs_composite_suspend(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev; + struct gadget_info *gi; + unsigned long flags; + + cdev = get_gadget_data(gadget); + if (!cdev) + return; + + gi = container_of(cdev, struct gadget_info, cdev); + spin_lock_irqsave(&gi->spinlock, flags); + cdev = get_gadget_data(gadget); + if (!cdev || gi->unbind) { + spin_unlock_irqrestore(&gi->spinlock, flags); + return; + } + + composite_suspend(gadget); + spin_unlock_irqrestore(&gi->spinlock, flags); +} + +static void configfs_composite_resume(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev; + struct gadget_info *gi; + unsigned long flags; + + cdev = get_gadget_data(gadget); + if (!cdev) + return; + + gi = container_of(cdev, struct gadget_info, cdev); + spin_lock_irqsave(&gi->spinlock, flags); + cdev = get_gadget_data(gadget); + if (!cdev || gi->unbind) { + spin_unlock_irqrestore(&gi->spinlock, flags); + return; + } + + composite_resume(gadget); + spin_unlock_irqrestore(&gi->spinlock, flags); } static const struct usb_gadget_driver configfs_driver_template = { .bind = configfs_composite_bind, .unbind = configfs_composite_unbind, - .setup = composite_setup, - .reset = composite_disconnect, - .disconnect = composite_disconnect, + .setup = configfs_composite_setup, + .reset = configfs_composite_disconnect, + .disconnect = configfs_composite_disconnect, - .suspend = composite_suspend, - .resume = composite_resume, + .suspend = configfs_composite_suspend, + .resume = configfs_composite_resume, .max_speed = USB_SPEED_SUPER, .driver = { -- 2.20.1