linux-toradex.git/drivers/usb/gadget, branch v4.10 Linux kernel for Apalis and Colibri modules usb: gadget: f_fs: Assorted buffer overflow checks. 2017-01-25T11:03:52+00:00 Vincent Pelletier plr.vincent@gmail.com 2017-01-18T00:57:44+00:00 83e526f2a2fa4b2e82b6bd3ddbb26b70acfa8947 OS descriptor head, when flagged as provided, is accessed without checking if it fits in provided buffer. Verify length before access. Also, there are other places where buffer length it checked after accessing offsets which are potentially past the end. Check buffer length before as well to fail cleanly. Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com> Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
OS descriptor head, when flagged as provided, is accessed without
checking if it fits in provided buffer. Verify length before access.
Also, there are other places where buffer length it checked
after accessing offsets which are potentially past the end. Check
buffer length before as well to fail cleanly.

Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb: gadget: udc: atmel: remove memory leak 2017-01-12T08:05:04+00:00 Alexandre Belloni alexandre.belloni@free-electrons.com 2017-01-11T12:11:08+00:00 32856eea7bf75dfb99b955ada6e147f553a11366 Commit bbe097f092b0 ("usb: gadget: udc: atmel: fix endpoint name") introduced a memory leak when unbinding the driver. The endpoint names would not be freed. Solve that by including the name as a string in struct usba_ep so it is freed when the endpoint is. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
Commit bbe097f092b0 ("usb: gadget: udc: atmel: fix endpoint name")
introduced a memory leak when unbinding the driver. The endpoint names
would not be freed. Solve that by including the name as a string in struct
usba_ep so it is freed when the endpoint is.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
usb: gadget: f_fs: Fix iterations on endpoints. 2017-01-12T08:00:30+00:00 Vincent Pelletier plr.vincent@gmail.com 2017-01-09T13:46:00+00:00 08f37148b6a915a6996c7dbef87769b9efee2dba When zero endpoints are declared for a function, there is no endpoint to disable, enable or free, so replace do...while loops with while loops. Change pre-decrement to post-decrement to iterate the same number of times when there are endpoints to process. Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
When zero endpoints are declared for a function, there is no endpoint
to disable, enable or free, so replace do...while loops with while loops.
Change pre-decrement to post-decrement to iterate the same number of times
when there are endpoints to process.

Signed-off-by: Vincent Pelletier <plr.vincent@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
usb: gadget: composite: Fix function used to free memory 2017-01-12T07:58:05+00:00 Christophe JAILLET christophe.jaillet@wanadoo.fr 2017-01-04T05:30:16+00:00 990758c53eafe5a220a780ed12e7b4d51b3df032 'cdev->os_desc_req' has been allocated with 'usb_ep_alloc_request()' so 'usb_ep_free_request()' should be used to free it. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
'cdev->os_desc_req' has been allocated with 'usb_ep_alloc_request()' so
'usb_ep_free_request()' should be used to free it.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
usb: gadget: Fix copy/pasted error message 2017-01-03T12:33:59+00:00 David Lechner david@lechnology.com 2017-01-02T23:28:39+00:00 43aef5c2ca90535b3227e97e71604291875444ed This fixes an error message that was probably copied and pasted. The same message is used for both the in and out endpoints, so it makes it impossible to know which one actually failed because both cases say "IN". Make the out endpoint error message say "OUT". Signed-off-by: David Lechner <david@lechnology.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
This fixes an error message that was probably copied and pasted. The same
message is used for both the in and out endpoints, so it makes it impossible
to know which one actually failed because both cases say "IN".

Make the out endpoint error message say "OUT".

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
usb: gadget: udc: core: fix return code of usb_gadget_probe_driver() 2017-01-02T08:55:29+00:00 Felix Hädicke felixhaedicke@web.de 2016-12-29T22:02:11+00:00 7b01738112608ce47083178ae2b9ebadf02d32cc This fixes a regression which was introduced by commit f1bddbb, by reverting a small fragment of commit 855ed04. If the following conditions were met, usb_gadget_probe_driver() returned 0, although the call was unsuccessful: 1. A particular UDC was specified by thge gadget driver (using member "udc_name" of struct usb_gadget_driver). 2. The UDC with this name is available. 3. Another gadget driver is already bound to this gadget. 4. The gadget driver has the "match_existing_only" flag set. In this case, the return code variable "ret" is set to 0, the return code of a strcmp() call (to check for the second condition). This also fixes an oops which could occur in the following scenario: 1. Two usb gadget instances were configured using configfs. 2. The first gadget configuration was bound to a UDC (using the configfs attribute "UDC"). 3. It was tried to bind the second gadget configuration to the same UDC in the same way. This operation was then wrongly reported as being successful. 4. The second gadget configuration's "UDC" attribute is cleared, to unbind the (not really bound) second gadget configuration from the UDC. <BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff94f5e5e9>] __list_del_entry+0x29/0xc0 PGD 41b4c5067 PUD 41a598067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: cdc_acm usb_f_fs usb_f_serial usb_f_acm u_serial libcomposite configfs dummy_hcd bnep intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm snd_hda_codec_hdmi irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd snd_hda_codec_realtek snd_hda_codec_generic serio_raw uvcvideo videobuf2_vmalloc btusb snd_usb_audio snd_hda_intel videobuf2_memops btrtl snd_hda_codec snd_hda_core snd_usbmidi_lib btbcm videobuf2_v4l2 btintel snd_hwdep videobuf2_core snd_seq_midi bluetooth snd_seq_midi_event videodev xpad efi_pstore snd_pcm_oss rfkill joydev media crc16 ff_memless snd_mixer_oss snd_rawmidi nls_ascii snd_pcm snd_seq snd_seq_device nls_cp437 mei_me snd_timer vfat sg udc_core lpc_ich fat efivars mfd_core mei snd soundcore battery nuvoton_cir rc_core evdev intel_smartconnect ie31200_edac edac_core shpchp tpm_tis tpm_tis_core tpm parport_pc ppdev lp parport efivarfs autofs4 btrfs xor raid6_pq hid_logitech_hidpp hid_logitech_dj hid_generic usbhid hid uas usb_storage sr_mod cdrom sd_mod ahci libahci nouveau i915 crc32c_intel i2c_algo_bit psmouse ttm xhci_pci libata scsi_mod ehci_pci drm_kms_helper xhci_hcd ehci_hcd r8169 mii usbcore drm nvme nvme_core fjes button [last unloaded: net2280] CPU: 5 PID: 829 Comm: bash Not tainted 4.9.0-rc7 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z77 Extreme3, BIOS P1.50 07/11/2013 task: ffff880419ce4040 task.stack: ffffc90002ed4000 RIP: 0010:[<ffffffff94f5e5e9>] [<ffffffff94f5e5e9>] __list_del_entry+0x29/0xc0 RSP: 0018:ffffc90002ed7d68 EFLAGS: 00010207 RAX: 0000000000000000 RBX: ffff88041787ec30 RCX: dead000000000200 RDX: 0000000000000000 RSI: ffff880417482002 RDI: ffff88041787ec30 RBP: ffffc90002ed7d68 R08: 0000000000000000 R09: 0000000000000010 R10: 0000000000000000 R11: ffff880419ce4040 R12: ffff88041787eb68 R13: ffff88041787eaa8 R14: ffff88041560a2c0 R15: 0000000000000001 FS: 00007fe4e49b8700(0000) GS:ffff88042f340000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000041b4c4000 CR4: 00000000001406e0 Stack: ffffc90002ed7d80 ffffffff94f5e68d ffffffffc0ae5ef0 ffffc90002ed7da0 ffffffffc0ae22aa ffff88041787e800 ffff88041787e800 ffffc90002ed7dc0 ffffffffc0d7a727 ffffffff952273fa ffff88041aba5760 ffffc90002ed7df8 Call Trace: [<ffffffff94f5e68d>] list_del+0xd/0x30 [<ffffffffc0ae22aa>] usb_gadget_unregister_driver+0xaa/0xc0 [udc_core] [<ffffffffc0d7a727>] unregister_gadget+0x27/0x60 [libcomposite] [<ffffffff952273fa>] ? mutex_lock+0x1a/0x30 [<ffffffffc0d7a9b8>] gadget_dev_desc_UDC_store+0x88/0xe0 [libcomposite] [<ffffffffc0af8aa0>] configfs_write_file+0xa0/0x100 [configfs] [<ffffffff94e10d27>] __vfs_write+0x37/0x160 [<ffffffff94e31430>] ? __fd_install+0x30/0xd0 [<ffffffff95229dae>] ? _raw_spin_unlock+0xe/0x10 [<ffffffff94e11458>] vfs_write+0xb8/0x1b0 [<ffffffff94e128f8>] SyS_write+0x58/0xc0 [<ffffffff94e31594>] ? __close_fd+0x94/0xc0 [<ffffffff9522a0fb>] entry_SYSCALL_64_fastpath+0x1e/0xad Code: 66 90 55 48 8b 07 48 b9 00 01 00 00 00 00 ad de 48 8b 57 08 48 89 e5 48 39 c8 74 29 48 b9 00 02 00 00 00 00 ad de 48 39 ca 74 3a <4c> 8b 02 4c 39 c7 75 52 4c 8b 40 08 4c 39 c7 75 66 48 89 50 08 RIP [<ffffffff94f5e5e9>] __list_del_entry+0x29/0xc0 RSP <ffffc90002ed7d68> CR2: 0000000000000000 ---[ end trace 99fc090ab3ff6cbc ]--- Fixes: f1bddbb ("usb: gadget: Fix binding to UDC via configfs interface") Signed-off-by: Felix Hädicke <felixhaedicke@web.de> Tested-by: Krzysztof Opasiak <k.opasiak@samsung.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
This fixes a regression which was introduced by commit f1bddbb, by
reverting a small fragment of commit 855ed04.

If the following conditions were met, usb_gadget_probe_driver() returned
0, although the call was unsuccessful:
1. A particular UDC was specified by thge gadget driver (using member
"udc_name" of struct usb_gadget_driver).
2. The UDC with this name is available.
3. Another gadget driver is already bound to this gadget.
4. The gadget driver has the "match_existing_only" flag set.
In this case, the return code variable "ret" is set to 0, the return
code of a strcmp() call (to check for the second condition).

This also fixes an oops which could occur in the following scenario:
1. Two usb gadget instances were configured using configfs.
2. The first gadget configuration was bound to a UDC (using the configfs
attribute "UDC").
3. It was tried to bind the second gadget configuration to the same UDC
in the same way. This operation was then wrongly reported as being
successful.
4. The second gadget configuration's "UDC" attribute is cleared, to
unbind the (not really bound) second gadget configuration from the UDC.

<BUG: unable to handle kernel NULL pointer dereference
at           (null)
IP: [<ffffffff94f5e5e9>] __list_del_entry+0x29/0xc0
PGD 41b4c5067
PUD 41a598067
PMD 0

Oops: 0000 [#1] SMP
Modules linked in: cdc_acm usb_f_fs usb_f_serial
usb_f_acm u_serial libcomposite configfs dummy_hcd bnep intel_rapl
x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm
snd_hda_codec_hdmi irqbypass crct10dif_pclmul crc32_pclmul
ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper
ablk_helper cryptd snd_hda_codec_realtek snd_hda_codec_generic serio_raw
uvcvideo videobuf2_vmalloc btusb snd_usb_audio snd_hda_intel
videobuf2_memops btrtl snd_hda_codec snd_hda_core snd_usbmidi_lib btbcm
videobuf2_v4l2 btintel snd_hwdep videobuf2_core snd_seq_midi bluetooth
snd_seq_midi_event videodev xpad efi_pstore snd_pcm_oss rfkill joydev
media crc16 ff_memless snd_mixer_oss snd_rawmidi nls_ascii snd_pcm
snd_seq snd_seq_device nls_cp437 mei_me snd_timer vfat sg udc_core
lpc_ich fat
efivars mfd_core mei snd soundcore battery nuvoton_cir rc_core evdev
intel_smartconnect ie31200_edac edac_core shpchp tpm_tis tpm_tis_core
tpm parport_pc ppdev lp parport efivarfs autofs4 btrfs xor raid6_pq
hid_logitech_hidpp hid_logitech_dj hid_generic usbhid hid uas
usb_storage sr_mod cdrom sd_mod ahci libahci nouveau i915 crc32c_intel
i2c_algo_bit psmouse ttm xhci_pci libata scsi_mod ehci_pci
drm_kms_helper xhci_hcd ehci_hcd r8169 mii usbcore drm nvme nvme_core
fjes button [last unloaded: net2280]
CPU: 5 PID: 829 Comm: bash Not tainted 4.9.0-rc7 #1
Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z77
Extreme3, BIOS P1.50 07/11/2013
task: ffff880419ce4040 task.stack: ffffc90002ed4000
RIP: 0010:[<ffffffff94f5e5e9>]  [<ffffffff94f5e5e9>]
__list_del_entry+0x29/0xc0
RSP: 0018:ffffc90002ed7d68  EFLAGS: 00010207
RAX: 0000000000000000 RBX: ffff88041787ec30 RCX: dead000000000200
RDX: 0000000000000000 RSI: ffff880417482002 RDI: ffff88041787ec30
RBP: ffffc90002ed7d68 R08: 0000000000000000 R09: 0000000000000010
R10: 0000000000000000 R11: ffff880419ce4040 R12: ffff88041787eb68
R13: ffff88041787eaa8 R14: ffff88041560a2c0 R15: 0000000000000001
FS:  00007fe4e49b8700(0000) GS:ffff88042f340000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000041b4c4000 CR4: 00000000001406e0
Stack:
ffffc90002ed7d80 ffffffff94f5e68d ffffffffc0ae5ef0 ffffc90002ed7da0
ffffffffc0ae22aa ffff88041787e800 ffff88041787e800 ffffc90002ed7dc0
ffffffffc0d7a727 ffffffff952273fa ffff88041aba5760 ffffc90002ed7df8
Call Trace:
[<ffffffff94f5e68d>] list_del+0xd/0x30
[<ffffffffc0ae22aa>] usb_gadget_unregister_driver+0xaa/0xc0 [udc_core]
[<ffffffffc0d7a727>] unregister_gadget+0x27/0x60 [libcomposite]
[<ffffffff952273fa>] ? mutex_lock+0x1a/0x30
[<ffffffffc0d7a9b8>] gadget_dev_desc_UDC_store+0x88/0xe0 [libcomposite]
[<ffffffffc0af8aa0>] configfs_write_file+0xa0/0x100 [configfs]
[<ffffffff94e10d27>] __vfs_write+0x37/0x160
[<ffffffff94e31430>] ? __fd_install+0x30/0xd0
[<ffffffff95229dae>] ? _raw_spin_unlock+0xe/0x10
[<ffffffff94e11458>] vfs_write+0xb8/0x1b0
[<ffffffff94e128f8>] SyS_write+0x58/0xc0
[<ffffffff94e31594>] ? __close_fd+0x94/0xc0
[<ffffffff9522a0fb>] entry_SYSCALL_64_fastpath+0x1e/0xad
Code: 66 90 55 48 8b 07 48 b9 00 01 00 00 00 00 ad de 48 8b 57 08 48 89
e5 48 39 c8 74 29 48 b9 00 02 00 00 00 00 ad de 48 39 ca 74 3a <4c> 8b
02 4c 39 c7 75 52 4c 8b 40 08 4c 39 c7 75 66 48 89 50 08
RIP  [<ffffffff94f5e5e9>] __list_del_entry+0x29/0xc0
RSP <ffffc90002ed7d68>
CR2: 0000000000000000
---[ end trace 99fc090ab3ff6cbc ]---

Fixes: f1bddbb ("usb: gadget: Fix binding to UDC via configfs
interface")
Signed-off-by: Felix Hädicke <felixhaedicke@web.de>
Tested-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
USB: gadgetfs: remove unnecessary assignment 2017-01-02T08:55:28+00:00 Alan Stern stern@rowland.harvard.edu 2016-12-09T20:25:15+00:00 890e6c236dcda6d45c5f0bdd23665636376f6831 The dev_config() routine in gadgetfs has a check that dev->dev->bNumConfigurations is equal to 1, and then contains a redundant line of code setting the value to 1. This patch removes the unnecessary assignment. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
The dev_config() routine in gadgetfs has a check that
dev->dev->bNumConfigurations is equal to 1, and then contains a
redundant line of code setting the value to 1.  This patch removes the
unnecessary assignment.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
USB: gadgetfs: fix checks of wTotalLength in config descriptors 2017-01-02T08:55:28+00:00 Alan Stern stern@rowland.harvard.edu 2016-12-09T20:24:24+00:00 1c069b057dcf64fada952eaa868d35f02bb0cfc2 Andrey Konovalov's fuzz testing of gadgetfs showed that we should improve the driver's checks for valid configuration descriptors passed in by the user. In particular, the driver needs to verify that the wTotalLength value in the descriptor is not too short (smaller than USB_DT_CONFIG_SIZE). And the check for whether wTotalLength is too large has to be changed, because the driver assumes there is always enough room remaining in the buffer to hold a device descriptor (at least USB_DT_DEVICE_SIZE bytes). This patch adds the additional check and fixes the existing check. It may do a little more than strictly necessary, but one extra check won't hurt. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: Andrey Konovalov <andreyknvl@google.com> CC: <stable@vger.kernel.org> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
Andrey Konovalov's fuzz testing of gadgetfs showed that we should
improve the driver's checks for valid configuration descriptors passed
in by the user.  In particular, the driver needs to verify that the
wTotalLength value in the descriptor is not too short (smaller
than USB_DT_CONFIG_SIZE).  And the check for whether wTotalLength is
too large has to be changed, because the driver assumes there is
always enough room remaining in the buffer to hold a device descriptor
(at least USB_DT_DEVICE_SIZE bytes).

This patch adds the additional check and fixes the existing check.  It
may do a little more than strictly necessary, but one extra check
won't hurt.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Andrey Konovalov <andreyknvl@google.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
USB: gadgetfs: fix use-after-free bug 2017-01-02T08:55:28+00:00 Alan Stern stern@rowland.harvard.edu 2016-12-09T20:18:43+00:00 add333a81a16abbd4f106266a2553677a165725f Andrey Konovalov reports that fuzz testing with syzkaller causes a KASAN use-after-free bug report in gadgetfs: BUG: KASAN: use-after-free in gadgetfs_setup+0x208a/0x20e0 at addr ffff88003dfe5bf2 Read of size 2 by task syz-executor0/22994 CPU: 3 PID: 22994 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #16 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff88006df06a18 ffffffff81f96aba ffffffffe0528500 1ffff1000dbe0cd6 ffffed000dbe0cce ffff88006df068f0 0000000041b58ab3 ffffffff8598b4c8 ffffffff81f96828 1ffff1000dbe0ccd ffff88006df06708 ffff88006df06748 Call Trace: <IRQ> [ 201.343209] [< inline >] __dump_stack lib/dump_stack.c:15 <IRQ> [ 201.343209] [<ffffffff81f96aba>] dump_stack+0x292/0x398 lib/dump_stack.c:51 [<ffffffff817e4dec>] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159 [< inline >] print_address_description mm/kasan/report.c:197 [<ffffffff817e5080>] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286 [< inline >] kasan_report mm/kasan/report.c:306 [<ffffffff817e562a>] __asan_report_load_n_noabort+0x3a/0x40 mm/kasan/report.c:337 [< inline >] config_buf drivers/usb/gadget/legacy/inode.c:1298 [<ffffffff8322c8fa>] gadgetfs_setup+0x208a/0x20e0 drivers/usb/gadget/legacy/inode.c:1368 [<ffffffff830fdcd0>] dummy_timer+0x11f0/0x36d0 drivers/usb/gadget/udc/dummy_hcd.c:1858 [<ffffffff814807c1>] call_timer_fn+0x241/0x800 kernel/time/timer.c:1308 [< inline >] expire_timers kernel/time/timer.c:1348 [<ffffffff81482de6>] __run_timers+0xa06/0xec0 kernel/time/timer.c:1641 [<ffffffff814832c1>] run_timer_softirq+0x21/0x80 kernel/time/timer.c:1654 [<ffffffff84f4af8b>] __do_softirq+0x2fb/0xb63 kernel/softirq.c:284 The cause of the bug is subtle. The dev_config() routine gets called twice by the fuzzer. The first time, the user data contains both a full-speed configuration descriptor and a high-speed config descriptor, causing dev->hs_config to be set. But it also contains an invalid device descriptor, so the buffer containing the descriptors is deallocated and dev_config() returns an error. The second time dev_config() is called, the user data contains only a full-speed config descriptor. But dev->hs_config still has the stale pointer remaining from the first call, causing the routine to think that there is a valid high-speed config. Later on, when the driver dereferences the stale pointer to copy that descriptor, we get a use-after-free access. The fix is simple: Clear dev->hs_config if the passed-in data does not contain a high-speed config descriptor. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> CC: <stable@vger.kernel.org> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
Andrey Konovalov reports that fuzz testing with syzkaller causes a
KASAN use-after-free bug report in gadgetfs:

BUG: KASAN: use-after-free in gadgetfs_setup+0x208a/0x20e0 at addr ffff88003dfe5bf2
Read of size 2 by task syz-executor0/22994
CPU: 3 PID: 22994 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #16
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 ffff88006df06a18 ffffffff81f96aba ffffffffe0528500 1ffff1000dbe0cd6
 ffffed000dbe0cce ffff88006df068f0 0000000041b58ab3 ffffffff8598b4c8
 ffffffff81f96828 1ffff1000dbe0ccd ffff88006df06708 ffff88006df06748
Call Trace:
 <IRQ> [  201.343209]  [<     inline     >] __dump_stack lib/dump_stack.c:15
 <IRQ> [  201.343209]  [<ffffffff81f96aba>] dump_stack+0x292/0x398 lib/dump_stack.c:51
 [<ffffffff817e4dec>] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
 [<     inline     >] print_address_description mm/kasan/report.c:197
 [<ffffffff817e5080>] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
 [<     inline     >] kasan_report mm/kasan/report.c:306
 [<ffffffff817e562a>] __asan_report_load_n_noabort+0x3a/0x40 mm/kasan/report.c:337
 [<     inline     >] config_buf drivers/usb/gadget/legacy/inode.c:1298
 [<ffffffff8322c8fa>] gadgetfs_setup+0x208a/0x20e0 drivers/usb/gadget/legacy/inode.c:1368
 [<ffffffff830fdcd0>] dummy_timer+0x11f0/0x36d0 drivers/usb/gadget/udc/dummy_hcd.c:1858
 [<ffffffff814807c1>] call_timer_fn+0x241/0x800 kernel/time/timer.c:1308
 [<     inline     >] expire_timers kernel/time/timer.c:1348
 [<ffffffff81482de6>] __run_timers+0xa06/0xec0 kernel/time/timer.c:1641
 [<ffffffff814832c1>] run_timer_softirq+0x21/0x80 kernel/time/timer.c:1654
 [<ffffffff84f4af8b>] __do_softirq+0x2fb/0xb63 kernel/softirq.c:284

The cause of the bug is subtle.  The dev_config() routine gets called
twice by the fuzzer.  The first time, the user data contains both a
full-speed configuration descriptor and a high-speed config
descriptor, causing dev->hs_config to be set.  But it also contains an
invalid device descriptor, so the buffer containing the descriptors is
deallocated and dev_config() returns an error.

The second time dev_config() is called, the user data contains only a
full-speed config descriptor.  But dev->hs_config still has the stale
pointer remaining from the first call, causing the routine to think
that there is a valid high-speed config.  Later on, when the driver
dereferences the stale pointer to copy that descriptor, we get a
use-after-free access.

The fix is simple: Clear dev->hs_config if the passed-in data does not
contain a high-speed config descriptor.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
USB: gadgetfs: fix unbounded memory allocation bug 2017-01-02T08:55:28+00:00 Alan Stern stern@rowland.harvard.edu 2016-12-09T20:17:46+00:00 faab50984fe6636e616c7cc3d30308ba391d36fd Andrey Konovalov reports that fuzz testing with syzkaller causes a KASAN warning in gadgetfs: BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr ffff88003c47e160 Write of size 65537 by task syz-executor0/6356 CPU: 3 PID: 6356 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #19 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff88003c107ad8 ffffffff81f96aba ffffffff3dc11ef0 1ffff10007820eee ffffed0007820ee6 ffff88003dc11f00 0000000041b58ab3 ffffffff8598b4c8 ffffffff81f96828 ffffffff813fb4a0 ffff88003b6eadc0 ffff88003c107738 Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81f96aba>] dump_stack+0x292/0x398 lib/dump_stack.c:51 [<ffffffff817e4dec>] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159 [< inline >] print_address_description mm/kasan/report.c:197 [<ffffffff817e5080>] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286 [<ffffffff817e5705>] kasan_report+0x35/0x40 mm/kasan/report.c:306 [< inline >] check_memory_region_inline mm/kasan/kasan.c:308 [<ffffffff817e3fb9>] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315 [<ffffffff817e4044>] kasan_check_write+0x14/0x20 mm/kasan/kasan.c:326 [< inline >] copy_from_user arch/x86/include/asm/uaccess.h:689 [< inline >] ep0_write drivers/usb/gadget/legacy/inode.c:1135 [<ffffffff83228caf>] dev_config+0x86f/0x1190 drivers/usb/gadget/legacy/inode.c:1759 [<ffffffff817fdd55>] __vfs_write+0x5d5/0x760 fs/read_write.c:510 [<ffffffff817ff650>] vfs_write+0x170/0x4e0 fs/read_write.c:560 [< inline >] SYSC_write fs/read_write.c:607 [<ffffffff81803a5b>] SyS_write+0xfb/0x230 fs/read_write.c:599 [<ffffffff84f47ec1>] entry_SYSCALL_64_fastpath+0x1f/0xc2 Indeed, there is a comment saying that the value of len is restricted to a 16-bit integer, but the code doesn't actually do this. This patch fixes the warning. It replaces the comment with a computation that forces the amount of data copied from the user in ep0_write() to be no larger than the wLength size for the control transfer, which is a 16-bit quantity. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> CC: <stable@vger.kernel.org> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> 
Andrey Konovalov reports that fuzz testing with syzkaller causes a
KASAN warning in gadgetfs:

BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr ffff88003c47e160
Write of size 65537 by task syz-executor0/6356
CPU: 3 PID: 6356 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 ffff88003c107ad8 ffffffff81f96aba ffffffff3dc11ef0 1ffff10007820eee
 ffffed0007820ee6 ffff88003dc11f00 0000000041b58ab3 ffffffff8598b4c8
 ffffffff81f96828 ffffffff813fb4a0 ffff88003b6eadc0 ffff88003c107738
Call Trace:
 [<     inline     >] __dump_stack lib/dump_stack.c:15
 [<ffffffff81f96aba>] dump_stack+0x292/0x398 lib/dump_stack.c:51
 [<ffffffff817e4dec>] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
 [<     inline     >] print_address_description mm/kasan/report.c:197
 [<ffffffff817e5080>] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
 [<ffffffff817e5705>] kasan_report+0x35/0x40 mm/kasan/report.c:306
 [<     inline     >] check_memory_region_inline mm/kasan/kasan.c:308
 [<ffffffff817e3fb9>] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
 [<ffffffff817e4044>] kasan_check_write+0x14/0x20 mm/kasan/kasan.c:326
 [<     inline     >] copy_from_user arch/x86/include/asm/uaccess.h:689
 [<     inline     >] ep0_write drivers/usb/gadget/legacy/inode.c:1135
 [<ffffffff83228caf>] dev_config+0x86f/0x1190 drivers/usb/gadget/legacy/inode.c:1759
 [<ffffffff817fdd55>] __vfs_write+0x5d5/0x760 fs/read_write.c:510
 [<ffffffff817ff650>] vfs_write+0x170/0x4e0 fs/read_write.c:560
 [<     inline     >] SYSC_write fs/read_write.c:607
 [<ffffffff81803a5b>] SyS_write+0xfb/0x230 fs/read_write.c:599
 [<ffffffff84f47ec1>] entry_SYSCALL_64_fastpath+0x1f/0xc2

Indeed, there is a comment saying that the value of len is restricted
to a 16-bit integer, but the code doesn't actually do this.

This patch fixes the warning.  It replaces the comment with a
computation that forces the amount of data copied from the user in
ep0_write() to be no larger than the wLength size for the control
transfer, which is a 16-bit quantity.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>