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KMSAN: uninit-value in mts_usb_probe

PATCH In review syzbot 3 participants 3 messages Oct 2, 2019 – Oct 3, 2019

Subsystems (3)
Stable branch USB Microtek X6 scanner
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author syzbot
#0 lore raw

Hello,

syzbot found the following crash on:

HEAD commit:    fe36eb20 kmsan: rework SLUB hooks
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=17605b6fa00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=40511ad0c5945201
dashboard link: https://syzkaller.appspot.com/bug?extid=5630ca7c3b2be5c9da5e
compiler:       clang version 9.0.0 (/home/glider/llvm/clang 80fee25776c2fb61e74c1ecb1a523375c2500b69)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11305710600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1506787fa00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:

Reported-by [email protected]

usb 1-1: config 0 interface 235 altsetting 0 bulk endpoint 0x5 has invalid maxpacket 0 usb 1-1: New USB device found, idVendor=05da, idProduct=009a, bcdDevice=46.6b usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
usb 1-1: config 0 descriptor??
microtek usb (rev 0.4.3): can only deal with bulk endpoints; endpoint 15 is not bulk. microtek usb (rev 0.4.3): can only deal with bulk endpoints; endpoint 10 is not bulk. microtek usb (rev 0.4.3): will this work? Command EP is not usually 5
==================================================================

BUG: KMSAN: uninit-value in mts_usb_probe+0xd1d/0xfb0 drivers/usb/image/microtek.c:754
CPU: 1 PID: 33 Comm: kworker/1:1 Not tainted 5.2.0-rc4+ #11
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
 mts_usb_probe+0xd1d/0xfb0 drivers/usb/image/microtek.c:754
 usb_probe_interface+0xd19/0x1310 drivers/usb/core/driver.c:361
 really_probe+0x1344/0x1d90 drivers/base/dd.c:513
 driver_probe_device+0x1ba/0x510 drivers/base/dd.c:670
 __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:777
 bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
 __device_attach+0x489/0x750 drivers/base/dd.c:843
 device_initial_probe+0x4a/0x60 drivers/base/dd.c:890
 bus_probe_device+0x131/0x390 drivers/base/bus.c:514
 device_add+0x25b5/0x2df0 drivers/base/core.c:2111
 usb_set_configuration+0x309f/0x3710 drivers/usb/core/message.c:2027
 generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
 usb_probe_device+0x146/0x200 drivers/usb/core/driver.c:266
 really_probe+0x1344/0x1d90 drivers/base/dd.c:513
 driver_probe_device+0x1ba/0x510 drivers/base/dd.c:670
 __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:777
 bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
 __device_attach+0x489/0x750 drivers/base/dd.c:843
 device_initial_probe+0x4a/0x60 drivers/base/dd.c:890
 bus_probe_device+0x131/0x390 drivers/base/bus.c:514
 device_add+0x25b5/0x2df0 drivers/base/core.c:2111
 usb_new_device+0x23e5/0x2fb0 drivers/usb/core/hub.c:2534
 hub_port_connect drivers/usb/core/hub.c:5089 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0x5853/0x7320 drivers/usb/core/hub.c:5432
 process_one_work+0x1572/0x1f00 kernel/workqueue.c:2269
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2415
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Uninit was stored to memory at:

 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:187 [inline]
 kmsan_internal_chain_origin+0xcc/0x150 mm/kmsan/kmsan.c:349
 __msan_chain_origin+0x6b/0xe0 mm/kmsan/kmsan_instr.c:190
 mts_usb_probe+0xcf7/0xfb0 drivers/usb/image/microtek.c:748
 usb_probe_interface+0xd19/0x1310 drivers/usb/core/driver.c:361
 really_probe+0x1344/0x1d90 drivers/base/dd.c:513
 driver_probe_device+0x1ba/0x510 drivers/base/dd.c:670
 __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:777
 bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
 __device_attach+0x489/0x750 drivers/base/dd.c:843
 device_initial_probe+0x4a/0x60 drivers/base/dd.c:890
 bus_probe_device+0x131/0x390 drivers/base/bus.c:514
 device_add+0x25b5/0x2df0 drivers/base/core.c:2111
 usb_set_configuration+0x309f/0x3710 drivers/usb/core/message.c:2027
 generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
 usb_probe_device+0x146/0x200 drivers/usb/core/driver.c:266
 really_probe+0x1344/0x1d90 drivers/base/dd.c:513
 driver_probe_device+0x1ba/0x510 drivers/base/dd.c:670
 __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:777
 bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
 __device_attach+0x489/0x750 drivers/base/dd.c:843
 device_initial_probe+0x4a/0x60 drivers/base/dd.c:890
 bus_probe_device+0x131/0x390 drivers/base/bus.c:514
 device_add+0x25b5/0x2df0 drivers/base/core.c:2111
 usb_new_device+0x23e5/0x2fb0 drivers/usb/core/hub.c:2534
 hub_port_connect drivers/usb/core/hub.c:5089 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0x5853/0x7320 drivers/usb/core/hub.c:5432
 process_one_work+0x1572/0x1f00 kernel/workqueue.c:2269
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2415
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Local variable description: ----ep_in_set@mts_usb_probe Variable was created at:

 mts_usb_probe+0x53/0xfb0 drivers/usb/image/microtek.c:666
 usb_probe_interface+0xd19/0x1310 drivers/usb/core/driver.c:361
==================================================================

---
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#1 lore raw

PATCH 1/1 USB: microtek: fix info-leak at probe

Add missing bulk-in endpoint sanity check to prevent uninitialised stack data from being reported to the system log and used as endpoint addresses.

Fixes 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc stable <[email protected]>
Reported-by [email protected]
Signed-off-by Johan Hovold <[email protected]>
---
 drivers/usb/image/microtek.c | 4 ++++
 1 file changed, 4 insertions(+)
drivers/usb/image/microtek.c +4 -0
index 0a57c2cc8e5a..7a6b122c833f 100644
@@ -716,6 +716,10 @@ static int mts_usb_probe(struct usb_interface *intf,
 
 	}
 
+	if (ep_in_current != &ep_in_set[2]) {
+		MTS_WARNING("couldn't find two input bulk endpoints. Bailing out.\n");
+		return -ENODEV;
+	}
 
 	if ( ep_out == -1 ) {
 		MTS_WARNING( "couldn't find an output bulk endpoint. Bailing out.\n" );
Signature · 1 line
2.23.0
Acked-by on v1 1/1
#2 lore raw

Re: [PATCH] USB: microtek: fix info-leak at probe

Am Donnerstag, den 03.10.2019, 09:09 +0200 schrieb Johan Hovold:

Quoted 8 lines

Add missing bulk-in endpoint sanity check to prevent uninitialised stack data from being reported to the system log and used as endpoint addresses.

Fixes 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc stable <[email protected]>
Reported-by [email protected]
Signed-off-by Johan Hovold <[email protected]>
Acked-by Oliver Neukum <[email protected]>