mirror of
https://github.com/torvalds/linux.git
synced 2024-09-21 07:23:06 +00:00
2af89ebacf
coresight devices track their connections (output connections) and
hold a reference to the fwnode. When a device goes away, we walk through
the devices on the coresight bus and make sure that the references
are dropped. This happens both ways:
a) For all output connections from the device, drop the reference to
the target device via coresight_release_platform_data()
b) Iterate over all the devices on the coresight bus and drop the
reference to fwnode if *this* device is the target of the output
connection, via coresight_remove_conns()->coresight_remove_match().
However, the coresight_remove_match() doesn't clear the fwnode field,
after dropping the reference, this causes use-after-free and
additional refcount drops on the fwnode.
e.g., if we have two devices, A and B, with a connection, A -> B.
If we remove B first, B would clear the reference on B, from A
via coresight_remove_match(). But when A is removed, it still has
a connection with fwnode still pointing to B. Thus it tries to drops
the reference in coresight_release_platform_data(), raising the bells
like :
[ 91.990153] ------------[ cut here ]------------
[ 91.990163] refcount_t: addition on 0; use-after-free.
[ 91.990212] WARNING: CPU: 0 PID: 461 at lib/refcount.c:25 refcount_warn_saturate+0xa0/0x144
[ 91.990260] Modules linked in: coresight_funnel coresight_replicator coresight_etm4x(-)
crct10dif_ce coresight ip_tables x_tables ipv6 [last unloaded: coresight_cpu_debug]
[ 91.990398] CPU: 0 PID: 461 Comm: rmmod Tainted: G W T 5.19.0-rc2+ #53
[ 91.990418] Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Feb 1 2019
[ 91.990434] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 91.990454] pc : refcount_warn_saturate+0xa0/0x144
[ 91.990476] lr : refcount_warn_saturate+0xa0/0x144
[ 91.990496] sp : ffff80000c843640
[ 91.990509] x29: ffff80000c843640 x28: ffff800009957c28 x27: ffff80000c8439a8
[ 91.990560] x26: ffff00097eff1990 x25: ffff8000092b6ad8 x24: ffff00097eff19a8
[ 91.990610] x23: ffff80000c8439a8 x22: 0000000000000000 x21: ffff80000c8439c2
[ 91.990659] x20: 0000000000000000 x19: ffff00097eff1a10 x18: ffff80000ab99c40
[ 91.990708] x17: 0000000000000000 x16: 0000000000000000 x15: ffff80000abf6fa0
[ 91.990756] x14: 000000000000001d x13: 0a2e656572662d72 x12: 657466612d657375
[ 91.990805] x11: 203b30206e6f206e x10: 6f69746964646120 x9 : ffff8000081aba28
[ 91.990854] x8 : 206e6f206e6f6974 x7 : 69646461203a745f x6 : 746e756f63666572
[ 91.990903] x5 : ffff00097648ec58 x4 : 0000000000000000 x3 : 0000000000000027
[ 91.990952] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff00080260ba00
[ 91.991000] Call trace:
[ 91.991012] refcount_warn_saturate+0xa0/0x144
[ 91.991034] kobject_get+0xac/0xb0
[ 91.991055] of_node_get+0x2c/0x40
[ 91.991076] of_fwnode_get+0x40/0x60
[ 91.991094] fwnode_handle_get+0x3c/0x60
[ 91.991116] fwnode_get_nth_parent+0xf4/0x110
[ 91.991137] fwnode_full_name_string+0x48/0xc0
[ 91.991158] device_node_string+0x41c/0x530
[ 91.991178] pointer+0x320/0x3ec
[ 91.991198] vsnprintf+0x23c/0x750
[ 91.991217] vprintk_store+0x104/0x4b0
[ 91.991238] vprintk_emit+0x8c/0x360
[ 91.991257] vprintk_default+0x44/0x50
[ 91.991276] vprintk+0xcc/0xf0
[ 91.991295] _printk+0x68/0x90
[ 91.991315] of_node_release+0x13c/0x14c
[ 91.991334] kobject_put+0x98/0x114
[ 91.991354] of_node_put+0x24/0x34
[ 91.991372] of_fwnode_put+0x40/0x5c
[ 91.991390] fwnode_handle_put+0x38/0x50
[ 91.991411] coresight_release_platform_data+0x74/0xb0 [coresight]
[ 91.991472] coresight_unregister+0x64/0xcc [coresight]
[ 91.991525] etm4_remove_dev+0x64/0x78 [coresight_etm4x]
[ 91.991563] etm4_remove_amba+0x1c/0x2c [coresight_etm4x]
[ 91.991598] amba_remove+0x3c/0x19c
Reproducible by: (Build all coresight components as modules):
#!/bin/sh
while true
do
for m in tmc stm cpu_debug etm4x replicator funnel
do
modprobe coresight_${m}
done
for m in tmc stm cpu_debug etm4x replicator funnel
do
rmmode coresight_${m}
done
done
Cc: stable@vger.kernel.org
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Fixes:
|
||
|---|---|---|
| .. | ||
| accessibility | ||
| acpi | ||
| amba | ||
| android | ||
| ata | ||
| atm | ||
| auxdisplay | ||
| base | ||
| bcma | ||
| block | ||
| bluetooth | ||
| bus | ||
| cdrom | ||
| char | ||
| clk | ||
| clocksource | ||
| comedi | ||
| connector | ||
| counter | ||
| cpufreq | ||
| cpuidle | ||
| crypto | ||
| cxl | ||
| dax | ||
| dca | ||
| devfreq | ||
| dio | ||
| dma | ||
| dma-buf | ||
| edac | ||
| eisa | ||
| extcon | ||
| firewire | ||
| firmware | ||
| fpga | ||
| fsi | ||
| gnss | ||
| gpio | ||
| gpu | ||
| greybus | ||
| hid | ||
| hsi | ||
| hte | ||
| hv | ||
| hwmon | ||
| hwspinlock | ||
| hwtracing | ||
| i2c | ||
| i3c | ||
| idle | ||
| iio | ||
| infiniband | ||
| input | ||
| interconnect | ||
| iommu | ||
| ipack | ||
| irqchip | ||
| isdn | ||
| leds | ||
| macintosh | ||
| mailbox | ||
| mcb | ||
| md | ||
| media | ||
| memory | ||
| memstick | ||
| message | ||
| mfd | ||
| misc | ||
| mmc | ||
| most | ||
| mtd | ||
| mux | ||
| net | ||
| nfc | ||
| ntb | ||
| nubus | ||
| nvdimm | ||
| nvme | ||
| nvmem | ||
| of | ||
| opp | ||
| parisc | ||
| parport | ||
| pci | ||
| pcmcia | ||
| peci | ||
| perf | ||
| phy | ||
| pinctrl | ||
| platform | ||
| pnp | ||
| power | ||
| powercap | ||
| pps | ||
| ps3 | ||
| ptp | ||
| pwm | ||
| rapidio | ||
| ras | ||
| regulator | ||
| remoteproc | ||
| reset | ||
| rpmsg | ||
| rtc | ||
| s390 | ||
| sbus | ||
| scsi | ||
| sh | ||
| siox | ||
| slimbus | ||
| soc | ||
| soundwire | ||
| spi | ||
| spmi | ||
| ssb | ||
| staging | ||
| target | ||
| tc | ||
| tee | ||
| thermal | ||
| thunderbolt | ||
| tty | ||
| ufs | ||
| uio | ||
| usb | ||
| vdpa | ||
| vfio | ||
| vhost | ||
| video | ||
| virt | ||
| virtio | ||
| vlynq | ||
| vme | ||
| w1 | ||
| watchdog | ||
| xen | ||
| zorro | ||
| Kconfig | ||
| Makefile | ||