From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Shuah Khan <skhan@linuxfoundation.org>
Subject: [PATCH 4.9 24/83] usbip: usbip_host: fix BUG: sleeping function called from invalid context
Date: Sun, 9 Jun 2019 18:41:54 +0200 [thread overview]
Message-ID: <20190609164129.597089766@linuxfoundation.org> (raw)
In-Reply-To: <20190609164127.843327870@linuxfoundation.org>
From: Shuah Khan <skhan@linuxfoundation.org>
commit 0c9e8b3cad654bfc499c10b652fbf8f0b890af8f upstream.
stub_probe() and stub_disconnect() call functions which could call
sleeping function in invalid context whil holding busid_lock.
Fix the problem by refining the lock holds to short critical sections
to change the busid_priv fields. This fix restructures the code to
limit the lock holds in stub_probe() and stub_disconnect().
stub_probe():
[15217.927028] BUG: sleeping function called from invalid context at mm/slab.h:418
[15217.927038] in_atomic(): 1, irqs_disabled(): 0, pid: 29087, name: usbip
[15217.927044] 5 locks held by usbip/29087:
[15217.927047] #0: 0000000091647f28 (sb_writers#6){....}, at: vfs_write+0x191/0x1c0
[15217.927062] #1: 000000008f9ba75b (&of->mutex){....}, at: kernfs_fop_write+0xf7/0x1b0
[15217.927072] #2: 00000000872e5b4b (&dev->mutex){....}, at: __device_driver_lock+0x3b/0x50
[15217.927082] #3: 00000000e74ececc (&dev->mutex){....}, at: __device_driver_lock+0x46/0x50
[15217.927090] #4: 00000000b20abbe0 (&(&busid_table[i].busid_lock)->rlock){....}, at: get_busid_priv+0x48/0x60 [usbip_host]
[15217.927103] CPU: 3 PID: 29087 Comm: usbip Tainted: G W 5.1.0-rc6+ #40
[15217.927106] Hardware name: Dell Inc. OptiPlex 790/0HY9JP, BIOS A18 09/24/2013
[15217.927109] Call Trace:
[15217.927118] dump_stack+0x63/0x85
[15217.927127] ___might_sleep+0xff/0x120
[15217.927133] __might_sleep+0x4a/0x80
[15217.927143] kmem_cache_alloc_trace+0x1aa/0x210
[15217.927156] stub_probe+0xe8/0x440 [usbip_host]
[15217.927171] usb_probe_device+0x34/0x70
stub_disconnect():
[15279.182478] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:908
[15279.182487] in_atomic(): 1, irqs_disabled(): 0, pid: 29114, name: usbip
[15279.182492] 5 locks held by usbip/29114:
[15279.182494] #0: 0000000091647f28 (sb_writers#6){....}, at: vfs_write+0x191/0x1c0
[15279.182506] #1: 00000000702cf0f3 (&of->mutex){....}, at: kernfs_fop_write+0xf7/0x1b0
[15279.182514] #2: 00000000872e5b4b (&dev->mutex){....}, at: __device_driver_lock+0x3b/0x50
[15279.182522] #3: 00000000e74ececc (&dev->mutex){....}, at: __device_driver_lock+0x46/0x50
[15279.182529] #4: 00000000b20abbe0 (&(&busid_table[i].busid_lock)->rlock){....}, at: get_busid_priv+0x48/0x60 [usbip_host]
[15279.182541] CPU: 0 PID: 29114 Comm: usbip Tainted: G W 5.1.0-rc6+ #40
[15279.182543] Hardware name: Dell Inc. OptiPlex 790/0HY9JP, BIOS A18 09/24/2013
[15279.182546] Call Trace:
[15279.182554] dump_stack+0x63/0x85
[15279.182561] ___might_sleep+0xff/0x120
[15279.182566] __might_sleep+0x4a/0x80
[15279.182574] __mutex_lock+0x55/0x950
[15279.182582] ? get_busid_priv+0x48/0x60 [usbip_host]
[15279.182587] ? reacquire_held_locks+0xec/0x1a0
[15279.182591] ? get_busid_priv+0x48/0x60 [usbip_host]
[15279.182597] ? find_held_lock+0x94/0xa0
[15279.182609] mutex_lock_nested+0x1b/0x20
[15279.182614] ? mutex_lock_nested+0x1b/0x20
[15279.182618] kernfs_remove_by_name_ns+0x2a/0x90
[15279.182625] sysfs_remove_file_ns+0x15/0x20
[15279.182629] device_remove_file+0x19/0x20
[15279.182634] stub_disconnect+0x6d/0x180 [usbip_host]
[15279.182643] usb_unbind_device+0x27/0x60
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/usbip/stub_dev.c | 65 ++++++++++++++++++++++++++++---------------
1 file changed, 43 insertions(+), 22 deletions(-)
--- a/drivers/usb/usbip/stub_dev.c
+++ b/drivers/usb/usbip/stub_dev.c
@@ -315,9 +315,17 @@ static int stub_probe(struct usb_device
const char *udev_busid = dev_name(&udev->dev);
struct bus_id_priv *busid_priv;
int rc = 0;
+ char save_status;
dev_dbg(&udev->dev, "Enter probe\n");
+ /* Not sure if this is our device. Allocate here to avoid
+ * calling alloc while holding busid_table lock.
+ */
+ sdev = stub_device_alloc(udev);
+ if (!sdev)
+ return -ENOMEM;
+
/* check we should claim or not by busid_table */
busid_priv = get_busid_priv(udev_busid);
if (!busid_priv || (busid_priv->status == STUB_BUSID_REMOV) ||
@@ -332,14 +340,14 @@ static int stub_probe(struct usb_device
* See driver_probe_device() in driver/base/dd.c
*/
rc = -ENODEV;
- goto call_put_busid_priv;
+ goto sdev_free;
}
if (udev->descriptor.bDeviceClass == USB_CLASS_HUB) {
dev_dbg(&udev->dev, "%s is a usb hub device... skip!\n",
udev_busid);
rc = -ENODEV;
- goto call_put_busid_priv;
+ goto sdev_free;
}
if (!strcmp(udev->bus->bus_name, "vhci_hcd")) {
@@ -348,15 +356,9 @@ static int stub_probe(struct usb_device
udev_busid);
rc = -ENODEV;
- goto call_put_busid_priv;
+ goto sdev_free;
}
- /* ok, this is my device */
- sdev = stub_device_alloc(udev);
- if (!sdev) {
- rc = -ENOMEM;
- goto call_put_busid_priv;
- }
dev_info(&udev->dev,
"usbip-host: register new device (bus %u dev %u)\n",
@@ -366,9 +368,13 @@ static int stub_probe(struct usb_device
/* set private data to usb_device */
dev_set_drvdata(&udev->dev, sdev);
+
busid_priv->sdev = sdev;
busid_priv->udev = udev;
+ save_status = busid_priv->status;
+ busid_priv->status = STUB_BUSID_ALLOC;
+
/*
* Claim this hub port.
* It doesn't matter what value we pass as owner
@@ -381,15 +387,16 @@ static int stub_probe(struct usb_device
goto err_port;
}
+ /* release the busid_lock */
+ put_busid_priv(busid_priv);
+
rc = stub_add_files(&udev->dev);
if (rc) {
dev_err(&udev->dev, "stub_add_files for %s\n", udev_busid);
goto err_files;
}
- busid_priv->status = STUB_BUSID_ALLOC;
- rc = 0;
- goto call_put_busid_priv;
+ return 0;
err_files:
usb_hub_release_port(udev->parent, udev->portnum,
@@ -398,23 +405,24 @@ err_port:
dev_set_drvdata(&udev->dev, NULL);
usb_put_dev(udev);
+ /* we already have busid_priv, just lock busid_lock */
+ spin_lock(&busid_priv->busid_lock);
busid_priv->sdev = NULL;
+ busid_priv->status = save_status;
+sdev_free:
stub_device_free(sdev);
-
-call_put_busid_priv:
+ /* release the busid_lock */
put_busid_priv(busid_priv);
+
return rc;
}
static void shutdown_busid(struct bus_id_priv *busid_priv)
{
- if (busid_priv->sdev && !busid_priv->shutdown_busid) {
- busid_priv->shutdown_busid = 1;
- usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
+ usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
- /* wait for the stop of the event handler */
- usbip_stop_eh(&busid_priv->sdev->ud);
- }
+ /* wait for the stop of the event handler */
+ usbip_stop_eh(&busid_priv->sdev->ud);
}
/*
@@ -446,6 +454,9 @@ static void stub_disconnect(struct usb_d
dev_set_drvdata(&udev->dev, NULL);
+ /* release busid_lock before call to remove device files */
+ put_busid_priv(busid_priv);
+
/*
* NOTE: rx/tx threads are invoked for each usb_device.
*/
@@ -456,18 +467,27 @@ static void stub_disconnect(struct usb_d
(struct usb_dev_state *) udev);
if (rc) {
dev_dbg(&udev->dev, "unable to release port\n");
- goto call_put_busid_priv;
+ return;
}
/* If usb reset is called from event handler */
if (usbip_in_eh(current))
- goto call_put_busid_priv;
+ return;
+
+ /* we already have busid_priv, just lock busid_lock */
+ spin_lock(&busid_priv->busid_lock);
+ if (!busid_priv->shutdown_busid)
+ busid_priv->shutdown_busid = 1;
+ /* release busid_lock */
+ put_busid_priv(busid_priv);
/* shutdown the current connection */
shutdown_busid(busid_priv);
usb_put_dev(sdev->udev);
+ /* we already have busid_priv, just lock busid_lock */
+ spin_lock(&busid_priv->busid_lock);
/* free sdev */
busid_priv->sdev = NULL;
stub_device_free(sdev);
@@ -476,6 +496,7 @@ static void stub_disconnect(struct usb_d
busid_priv->status = STUB_BUSID_ADDED;
call_put_busid_priv:
+ /* release busid_lock */
put_busid_priv(busid_priv);
}
next prev parent reply other threads:[~2019-06-09 17:16 UTC|newest]
Thread overview: 93+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-09 16:41 [PATCH 4.9 00/83] 4.9.181-stable review Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 01/83] ipv6: Consider sk_bound_dev_if when binding a raw socket to an address Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 02/83] llc: fix skb leak in llc_build_and_send_ui_pkt() Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 03/83] net: fec: fix the clk mismatch in failed_reset path Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 04/83] net-gro: fix use-after-free read in napi_gro_frags() Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 05/83] net: stmmac: fix reset gpio free missing Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 06/83] usbnet: fix kernel crash after disconnect Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 07/83] tipc: Avoid copying bytes beyond the supplied data Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 08/83] bnxt_en: Fix aggregation buffer leak under OOM condition Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 09/83] ipv4/igmp: fix another memory leak in igmpv3_del_delrec() Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 10/83] ipv4/igmp: fix build error if !CONFIG_IP_MULTICAST Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 11/83] net: dsa: mv88e6xxx: fix handling of upper half of STATS_TYPE_PORT Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 12/83] net: mvneta: Fix err code path of probe Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 13/83] net: mvpp2: fix bad MVPP2_TXQ_SCHED_TOKEN_CNTR_REG queue value Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 14/83] crypto: vmx - ghash: do nosimd fallback manually Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 15/83] xen/pciback: Dont disable PCI_COMMAND on PCI device reset Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 16/83] Revert "tipc: fix modprobe tipc failed after switch order of device registration" Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 17/83] tipc: fix modprobe tipc failed after switch order of device registration Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 18/83] sparc64: Fix regression in non-hypervisor TLB flush xcall Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 19/83] include/linux/bitops.h: sanitize rotate primitives Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 20/83] xhci: update bounce buffer with correct sg num Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 21/83] xhci: Use %zu for printing size_t type Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 22/83] xhci: Convert xhci_handshake() to use readl_poll_timeout_atomic() Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 23/83] usb: xhci: avoid null pointer deref when bos field is NULL Greg Kroah-Hartman
2019-06-09 16:41 ` Greg Kroah-Hartman [this message]
2019-06-09 16:41 ` [PATCH 4.9 25/83] usbip: usbip_host: fix stub_dev lock context imbalance regression Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 26/83] USB: Fix slab-out-of-bounds write in usb_get_bos_descriptor Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 27/83] USB: sisusbvga: fix oops in error path of sisusb_probe Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 28/83] USB: Add LPM quirk for Surface Dock GigE adapter Greg Kroah-Hartman
2019-06-09 16:41 ` [PATCH 4.9 29/83] USB: rio500: refuse more than one device at a time Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 30/83] USB: rio500: fix memory leak in close after disconnect Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 31/83] media: usb: siano: Fix general protection fault in smsusb Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 32/83] media: usb: siano: Fix false-positive "uninitialized variable" warning Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 33/83] media: smsusb: better handle optional alignment Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 34/83] scsi: zfcp: fix missing zfcp_port reference put on -EBUSY from port_remove Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 35/83] scsi: zfcp: fix to prevent port_remove with pure auto scan LUNs (only sdevs) Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 36/83] Btrfs: fix race updating log root item during fsync Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 37/83] powerpc/perf: Fix MMCRA corruption by bhrb_filter Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 38/83] ALSA: hda/realtek - Set default power save node to 0 Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 39/83] drm/nouveau/i2c: Disable i2c bus access after ->fini() Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 40/83] tty: serial: msm_serial: Fix XON/XOFF Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 41/83] tty: max310x: Fix external crystal register setup Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 42/83] memcg: make it work on sparse non-0-node systems Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 43/83] kernel/signal.c: trace_signal_deliver when signal_group_exit Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 44/83] docs: Fix conf.py for Sphinx 2.0 Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 45/83] staging: vc04_services: prevent integer overflow in create_pagelist() Greg Kroah-Hartman
2019-06-19 16:02 ` Martin Weinelt
2019-06-19 17:13 ` Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 46/83] CIFS: cifs_read_allocate_pages: dont iterate through whole page array on ENOMEM Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 47/83] gcc-plugins: Fix build failures under Darwin host Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 48/83] drm/vmwgfx: Dont send drm sysfs hotplug events on initial master set Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 49/83] brcmfmac: add length checks in scheduled scan result handler Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 50/83] brcmfmac: assure SSID length from firmware is limited Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 51/83] brcmfmac: add subtype check for event handling in data path Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 52/83] binder: Replace "%p" with "%pK" for stable Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 53/83] binder: replace "%p" with "%pK" Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 54/83] fs: prevent page refcount overflow in pipe_buf_get Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 55/83] mm, gup: remove broken VM_BUG_ON_PAGE compound check for hugepages Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 56/83] mm, gup: ensure real head page is ref-counted when using hugepages Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 57/83] mm: prevent get_user_pages() from overflowing page refcount Greg Kroah-Hartman
2019-07-31 15:14 ` Vlastimil Babka
2019-06-09 16:42 ` [PATCH 4.9 58/83] mm: make page ref count overflow check tighter and more explicit Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 59/83] Revert "x86/build: Move _etext to actual end of .text" Greg Kroah-Hartman
2019-06-10 11:57 ` Willy Tarreau
2019-06-09 16:42 ` [PATCH 4.9 60/83] efi/libstub: Unify command line param parsing Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 61/83] media: uvcvideo: Fix uvc_alloc_entity() allocation alignment Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 62/83] ethtool: fix potential userspace buffer overflow Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 63/83] neighbor: Call __ipv4_neigh_lookup_noref in neigh_xmit Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 64/83] net/mlx4_en: ethtool, Remove unsupported SFP EEPROM high pages query Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 65/83] net: rds: fix memory leak in rds_ib_flush_mr_pool Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 66/83] pktgen: do not sleep with the thread lock held Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 67/83] ipv6: fix EFAULT on sendto with icmpv6 and hdrincl Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 68/83] ipv6: use READ_ONCE() for inet->hdrincl as in ipv4 Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 69/83] Revert "fib_rules: fix error in backport of e9919a24d302 ("fib_rules: return 0...")" Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 70/83] Revert "fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied" Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 71/83] rcu: locking and unlocking need to always be at least barriers Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 72/83] parisc: Use implicit space register selection for loading the coherence index of I/O pdirs Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 73/83] fuse: fallocate: fix return with locked inode Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 74/83] x86/power: Fix nosmt vs hibernation triple fault during resume Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 75/83] MIPS: pistachio: Build uImage.gz by default Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 76/83] Revert "MIPS: perf: ath79: Fix perfcount IRQ assignment" Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 77/83] genwqe: Prevent an integer overflow in the ioctl Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 78/83] drm/gma500/cdv: Check vbt config bits when detecting lvds panels Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 79/83] drm/radeon: prefer lower reference dividers Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 80/83] drm/i915: Fix I915_EXEC_RING_MASK Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 81/83] TTY: serial_core, add ->install Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 82/83] fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock Greg Kroah-Hartman
2019-06-09 16:42 ` [PATCH 4.9 83/83] fuse: Add FOPEN_STREAM to use stream_open() Greg Kroah-Hartman
2019-06-09 22:10 ` [PATCH 4.9 00/83] 4.9.181-stable review kernelci.org bot
2019-06-10 6:38 ` Naresh Kamboju
2019-06-10 8:50 ` Jon Hunter
2019-06-10 14:42 ` Guenter Roeck
2019-06-10 21:49 ` shuah
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