Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-28 Thread Felipe Balbi 

Hi,

Alan Stern  writes:
>> > Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
>> > ===
>> > --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
>> > +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
>> > @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
>> >/* data and/or status stage for control request */
>> >} else if (dev->state == STATE_DEV_SETUP) {
>> >  
>> > -  /* IN DATA+STATUS caller makes len <= wLength */
>> > +  len = min(len, (size_t) dev->setup_wLength);
>> >if (dev->setup_in) {
>> >retval = setup_req (dev->gadget->ep0, dev->req, len);
>> >if (retval == 0) {
>> >
>> 
>> I already have a patch from Greg for this. See [1]
>> 
>> [1] 
>> https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?id=230bc0cb8ff222d9f0fbbd93a80393140b39481f
>
> The two patches fix different problems.  My patch goes on the pathway
> where dev->state > STATE_DEV_OPENED in dev_config(), and Greg's patch
> handles the case where it is <=.

Okay, here's what I have so far in my testing/fixes:

$ git --no-pager shortlog testing/fixes ^linus/master
Alan Stern (5):
  USB: dummy-hcd: fix bug in stop_activity (handle ep0)
  USB: gadgetfs: fix unbounded memory allocation bug
  USB: gadgetfs: fix use-after-free bug
  USB: gadgetfs: fix checks of wTotalLength in config descriptors
  USB: gadgetfs: remove unnecessary assignment

Baolin Wang (1):
  usb: gadget: f_fs: Fix possibe deadlock

Felipe Balbi (4):
  usb: dwc3: ep0: add dwc3_ep0_prepare_one_trb()
  usb: dwc3: ep0: explicitly call dwc3_ep0_prepare_one_trb()
  usb: dwc3: gadget: always unmap EP0 requests
  usb: dwc3: core: avoid Overflow events

Greg Kroah-Hartman (1):
  usb: gadgetfs: restrict upper bound on device configuration size

Grygorii Strashko (1):
  usb: dwc3: omap: fix race of pm runtime with irq handler in probe

Hans de Goede (1):
  usb: dwc3: pci: Fix dr_mode misspelling

Heikki Krogerus (1):
  usb: dwc3: pci: add Intel Gemini Lake PCI ID

Janusz Dziedzic (1):
  usb: dwc3: skip interrupt when ep disabled

John Youn (1):
  usb: dwc3: pci: Add "linux,sysdev_is_parent" property

Krzysztof Opasiak (1):
  usb: gadget: composite: Test get_alt() presence instead of set_alt()

Marek Szyprowski (1):
  usb: dwc2: fix flags for DMA descriptor allocation in dwc2_hsotg_ep_enable

Stefan Wahren (4):
  usb: dwc2: Do not set host parameter in peripheral mode
  usb: dwc2: fix dwc2_get_device_property for u8 and u16
  usb: dwc2: fix default value for DMA support
  usb: dwc2: gadget: fix default value for gadget-dma-desc

Vincent Pelletier (2):
  usb: gadget: f_fs: Document eventfd effect on descriptor format.
  usb: gadget: f_fs: Fix ExtCompat descriptor validation


-- 
balbi


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Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-28 Thread Felipe Balbi 

Hi,

Alan Stern  writes:
>> > Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
>> > ===
>> > --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
>> > +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
>> > @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
>> >/* data and/or status stage for control request */
>> >} else if (dev->state == STATE_DEV_SETUP) {
>> >  
>> > -  /* IN DATA+STATUS caller makes len <= wLength */
>> > +  len = min(len, (size_t) dev->setup_wLength);
>> >if (dev->setup_in) {
>> >retval = setup_req (dev->gadget->ep0, dev->req, len);
>> >if (retval == 0) {
>> >
>> 
>> I already have a patch from Greg for this. See [1]
>> 
>> [1] 
>> https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?id=230bc0cb8ff222d9f0fbbd93a80393140b39481f
>
> The two patches fix different problems.  My patch goes on the pathway
> where dev->state > STATE_DEV_OPENED in dev_config(), and Greg's patch
> handles the case where it is <=.

Okay, here's what I have so far in my testing/fixes:

$ git --no-pager shortlog testing/fixes ^linus/master
Alan Stern (5):
  USB: dummy-hcd: fix bug in stop_activity (handle ep0)
  USB: gadgetfs: fix unbounded memory allocation bug
  USB: gadgetfs: fix use-after-free bug
  USB: gadgetfs: fix checks of wTotalLength in config descriptors
  USB: gadgetfs: remove unnecessary assignment

Baolin Wang (1):
  usb: gadget: f_fs: Fix possibe deadlock

Felipe Balbi (4):
  usb: dwc3: ep0: add dwc3_ep0_prepare_one_trb()
  usb: dwc3: ep0: explicitly call dwc3_ep0_prepare_one_trb()
  usb: dwc3: gadget: always unmap EP0 requests
  usb: dwc3: core: avoid Overflow events

Greg Kroah-Hartman (1):
  usb: gadgetfs: restrict upper bound on device configuration size

Grygorii Strashko (1):
  usb: dwc3: omap: fix race of pm runtime with irq handler in probe

Hans de Goede (1):
  usb: dwc3: pci: Fix dr_mode misspelling

Heikki Krogerus (1):
  usb: dwc3: pci: add Intel Gemini Lake PCI ID

Janusz Dziedzic (1):
  usb: dwc3: skip interrupt when ep disabled

John Youn (1):
  usb: dwc3: pci: Add "linux,sysdev_is_parent" property

Krzysztof Opasiak (1):
  usb: gadget: composite: Test get_alt() presence instead of set_alt()

Marek Szyprowski (1):
  usb: dwc2: fix flags for DMA descriptor allocation in dwc2_hsotg_ep_enable

Stefan Wahren (4):
  usb: dwc2: Do not set host parameter in peripheral mode
  usb: dwc2: fix dwc2_get_device_property for u8 and u16
  usb: dwc2: fix default value for DMA support
  usb: dwc2: gadget: fix default value for gadget-dma-desc

Vincent Pelletier (2):
  usb: gadget: f_fs: Document eventfd effect on descriptor format.
  usb: gadget: f_fs: Fix ExtCompat descriptor validation


-- 
balbi


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Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-27 Thread Alan Stern 
On Tue, 27 Dec 2016, Felipe Balbi wrote:

> 
> Hi,
> 
> Alan Stern  writes:
> > On Tue, 6 Dec 2016, Andrey Konovalov wrote:
> >
> >> Hi!
> >> 
> >> I've got the following error report while running the syzkaller fuzzer.
> >> 
> >> ep0_write() doesn't check the length, so a user can cause an
> >> out-of-bounds with both size and data controlled.
> >> There's a comment which says "IN DATA+STATUS caller makes len <=
> >> wLength". While I'm not exactly sure what that means, the length seems
> >> to be passed unmodified directly from dev_config().
> >
> > You're right about the comment being misleading.  It looks like 
> > somebody forgot to actually do the check.
> >
> >> This doesn't seem to be a critical security issue since gadgetfs can't
> >> be mounted from a user namespace.
> >> 
> >> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
> >> 
> >> ==
> >> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
> >> 88003c47e160
> >> 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
> >>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
> >>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
> >>  81f96828 813fb4a0 88003b6eadc0 88003c107738
> >> Call Trace:
> >>  [< inline >] __dump_stack lib/dump_stack.c:15
> >>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
> >>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
> >>  [< inline >] print_address_description mm/kasan/report.c:197
> >>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
> >>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
> >>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
> >>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
> >>  [] 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
> >>  [] dev_config+0x86f/0x1190
> >> drivers/usb/gadget/legacy/inode.c:1759
> >>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
> >>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
> >>  [< inline >] SYSC_write fs/read_write.c:607
> >>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
> >>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2
> >
> > How does this patch work out?
> >
> > Alan Stern
> >
> >
> >
> > Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
> > ===
> > --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
> > +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
> > @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
> > /* data and/or status stage for control request */
> > } else if (dev->state == STATE_DEV_SETUP) {
> >  
> > -   /* IN DATA+STATUS caller makes len <= wLength */
> > +   len = min(len, (size_t) dev->setup_wLength);
> > if (dev->setup_in) {
> > retval = setup_req (dev->gadget->ep0, dev->req, len);
> > if (retval == 0) {
> >
> 
> I already have a patch from Greg for this. See [1]
> 
> [1] 
> https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?id=230bc0cb8ff222d9f0fbbd93a80393140b39481f

The two patches fix different problems.  My patch goes on the pathway
where dev->state > STATE_DEV_OPENED in dev_config(), and Greg's patch
handles the case where it is <=.

Alan Stern

Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-27 Thread Alan Stern 
On Tue, 27 Dec 2016, Felipe Balbi wrote:

> 
> Hi,
> 
> Alan Stern  writes:
> > On Tue, 6 Dec 2016, Andrey Konovalov wrote:
> >
> >> Hi!
> >> 
> >> I've got the following error report while running the syzkaller fuzzer.
> >> 
> >> ep0_write() doesn't check the length, so a user can cause an
> >> out-of-bounds with both size and data controlled.
> >> There's a comment which says "IN DATA+STATUS caller makes len <=
> >> wLength". While I'm not exactly sure what that means, the length seems
> >> to be passed unmodified directly from dev_config().
> >
> > You're right about the comment being misleading.  It looks like 
> > somebody forgot to actually do the check.
> >
> >> This doesn't seem to be a critical security issue since gadgetfs can't
> >> be mounted from a user namespace.
> >> 
> >> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
> >> 
> >> ==
> >> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
> >> 88003c47e160
> >> 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
> >>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
> >>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
> >>  81f96828 813fb4a0 88003b6eadc0 88003c107738
> >> Call Trace:
> >>  [< inline >] __dump_stack lib/dump_stack.c:15
> >>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
> >>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
> >>  [< inline >] print_address_description mm/kasan/report.c:197
> >>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
> >>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
> >>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
> >>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
> >>  [] 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
> >>  [] dev_config+0x86f/0x1190
> >> drivers/usb/gadget/legacy/inode.c:1759
> >>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
> >>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
> >>  [< inline >] SYSC_write fs/read_write.c:607
> >>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
> >>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2
> >
> > How does this patch work out?
> >
> > Alan Stern
> >
> >
> >
> > Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
> > ===
> > --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
> > +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
> > @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
> > /* data and/or status stage for control request */
> > } else if (dev->state == STATE_DEV_SETUP) {
> >  
> > -   /* IN DATA+STATUS caller makes len <= wLength */
> > +   len = min(len, (size_t) dev->setup_wLength);
> > if (dev->setup_in) {
> > retval = setup_req (dev->gadget->ep0, dev->req, len);
> > if (retval == 0) {
> >
> 
> I already have a patch from Greg for this. See [1]
> 
> [1] 
> https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?id=230bc0cb8ff222d9f0fbbd93a80393140b39481f

The two patches fix different problems.  My patch goes on the pathway
where dev->state > STATE_DEV_OPENED in dev_config(), and Greg's patch
handles the case where it is <=.

Alan Stern

Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-27 Thread Felipe Balbi 

Hi,

Alan Stern  writes:
> On Tue, 6 Dec 2016, Andrey Konovalov wrote:
>
>> Hi!
>> 
>> I've got the following error report while running the syzkaller fuzzer.
>> 
>> ep0_write() doesn't check the length, so a user can cause an
>> out-of-bounds with both size and data controlled.
>> There's a comment which says "IN DATA+STATUS caller makes len <=
>> wLength". While I'm not exactly sure what that means, the length seems
>> to be passed unmodified directly from dev_config().
>
> You're right about the comment being misleading.  It looks like 
> somebody forgot to actually do the check.
>
>> This doesn't seem to be a critical security issue since gadgetfs can't
>> be mounted from a user namespace.
>> 
>> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
>> 
>> ==
>> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
>> 88003c47e160
>> 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
>>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
>>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
>>  81f96828 813fb4a0 88003b6eadc0 88003c107738
>> Call Trace:
>>  [< inline >] __dump_stack lib/dump_stack.c:15
>>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
>>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
>>  [< inline >] print_address_description mm/kasan/report.c:197
>>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
>>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
>>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
>>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
>>  [] 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
>>  [] dev_config+0x86f/0x1190
>> drivers/usb/gadget/legacy/inode.c:1759
>>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
>>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
>>  [< inline >] SYSC_write fs/read_write.c:607
>>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
>>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2
>
> How does this patch work out?
>
> Alan Stern
>
>
>
> Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
> ===
> --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
> +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
> @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
>   /* data and/or status stage for control request */
>   } else if (dev->state == STATE_DEV_SETUP) {
>  
> - /* IN DATA+STATUS caller makes len <= wLength */
> + len = min(len, (size_t) dev->setup_wLength);
>   if (dev->setup_in) {
>   retval = setup_req (dev->gadget->ep0, dev->req, len);
>   if (retval == 0) {
>

I already have a patch from Greg for this. See [1]

[1] 
https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?id=230bc0cb8ff222d9f0fbbd93a80393140b39481f

-- 
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Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-27 Thread Felipe Balbi 

Hi,

Alan Stern  writes:
> On Tue, 6 Dec 2016, Andrey Konovalov wrote:
>
>> Hi!
>> 
>> I've got the following error report while running the syzkaller fuzzer.
>> 
>> ep0_write() doesn't check the length, so a user can cause an
>> out-of-bounds with both size and data controlled.
>> There's a comment which says "IN DATA+STATUS caller makes len <=
>> wLength". While I'm not exactly sure what that means, the length seems
>> to be passed unmodified directly from dev_config().
>
> You're right about the comment being misleading.  It looks like 
> somebody forgot to actually do the check.
>
>> This doesn't seem to be a critical security issue since gadgetfs can't
>> be mounted from a user namespace.
>> 
>> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
>> 
>> ==
>> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
>> 88003c47e160
>> 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
>>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
>>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
>>  81f96828 813fb4a0 88003b6eadc0 88003c107738
>> Call Trace:
>>  [< inline >] __dump_stack lib/dump_stack.c:15
>>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
>>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
>>  [< inline >] print_address_description mm/kasan/report.c:197
>>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
>>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
>>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
>>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
>>  [] 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
>>  [] dev_config+0x86f/0x1190
>> drivers/usb/gadget/legacy/inode.c:1759
>>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
>>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
>>  [< inline >] SYSC_write fs/read_write.c:607
>>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
>>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2
>
> How does this patch work out?
>
> Alan Stern
>
>
>
> Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
> ===
> --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
> +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
> @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
>   /* data and/or status stage for control request */
>   } else if (dev->state == STATE_DEV_SETUP) {
>  
> - /* IN DATA+STATUS caller makes len <= wLength */
> + len = min(len, (size_t) dev->setup_wLength);
>   if (dev->setup_in) {
>   retval = setup_req (dev->gadget->ep0, dev->req, len);
>   if (retval == 0) {
>

I already have a patch from Greg for this. See [1]

[1] 
https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?id=230bc0cb8ff222d9f0fbbd93a80393140b39481f

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Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-06 Thread Andrey Konovalov 
On Tue, Dec 6, 2016 at 4:30 PM, Alan Stern  wrote:
> On Tue, 6 Dec 2016, Andrey Konovalov wrote:
>
>> Hi!
>>
>> I've got the following error report while running the syzkaller fuzzer.
>>
>> ep0_write() doesn't check the length, so a user can cause an
>> out-of-bounds with both size and data controlled.
>> There's a comment which says "IN DATA+STATUS caller makes len <=
>> wLength". While I'm not exactly sure what that means, the length seems
>> to be passed unmodified directly from dev_config().
>
> You're right about the comment being misleading.  It looks like
> somebody forgot to actually do the check.
>
>> This doesn't seem to be a critical security issue since gadgetfs can't
>> be mounted from a user namespace.
>>
>> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
>>
>> ==
>> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
>> 88003c47e160
>> 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
>>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
>>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
>>  81f96828 813fb4a0 88003b6eadc0 88003c107738
>> Call Trace:
>>  [< inline >] __dump_stack lib/dump_stack.c:15
>>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
>>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
>>  [< inline >] print_address_description mm/kasan/report.c:197
>>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
>>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
>>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
>>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
>>  [] 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
>>  [] dev_config+0x86f/0x1190
>> drivers/usb/gadget/legacy/inode.c:1759
>>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
>>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
>>  [< inline >] SYSC_write fs/read_write.c:607
>>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
>>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2
>
> How does this patch work out?

I believe it fixes the issue.

Thanks!

>
> Alan Stern
>
>
>
> Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
> ===
> --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
> +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
> @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
> /* data and/or status stage for control request */
> } else if (dev->state == STATE_DEV_SETUP) {
>
> -   /* IN DATA+STATUS caller makes len <= wLength */
> +   len = min(len, (size_t) dev->setup_wLength);
> if (dev->setup_in) {
> retval = setup_req (dev->gadget->ep0, dev->req, len);
> if (retval == 0) {
>

Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-06 Thread Andrey Konovalov 
On Tue, Dec 6, 2016 at 4:30 PM, Alan Stern  wrote:
> On Tue, 6 Dec 2016, Andrey Konovalov wrote:
>
>> Hi!
>>
>> I've got the following error report while running the syzkaller fuzzer.
>>
>> ep0_write() doesn't check the length, so a user can cause an
>> out-of-bounds with both size and data controlled.
>> There's a comment which says "IN DATA+STATUS caller makes len <=
>> wLength". While I'm not exactly sure what that means, the length seems
>> to be passed unmodified directly from dev_config().
>
> You're right about the comment being misleading.  It looks like
> somebody forgot to actually do the check.
>
>> This doesn't seem to be a critical security issue since gadgetfs can't
>> be mounted from a user namespace.
>>
>> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
>>
>> ==
>> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
>> 88003c47e160
>> 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
>>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
>>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
>>  81f96828 813fb4a0 88003b6eadc0 88003c107738
>> Call Trace:
>>  [< inline >] __dump_stack lib/dump_stack.c:15
>>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
>>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
>>  [< inline >] print_address_description mm/kasan/report.c:197
>>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
>>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
>>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
>>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
>>  [] 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
>>  [] dev_config+0x86f/0x1190
>> drivers/usb/gadget/legacy/inode.c:1759
>>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
>>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
>>  [< inline >] SYSC_write fs/read_write.c:607
>>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
>>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2
>
> How does this patch work out?

I believe it fixes the issue.

Thanks!

>
> Alan Stern
>
>
>
> Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
> ===
> --- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
> +++ usb-4.x/drivers/usb/gadget/legacy/inode.c
> @@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
> /* data and/or status stage for control request */
> } else if (dev->state == STATE_DEV_SETUP) {
>
> -   /* IN DATA+STATUS caller makes len <= wLength */
> +   len = min(len, (size_t) dev->setup_wLength);
> if (dev->setup_in) {
> retval = setup_req (dev->gadget->ep0, dev->req, len);
> if (retval == 0) {
>

Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-06 Thread Alan Stern 
On Tue, 6 Dec 2016, Andrey Konovalov wrote:

> Hi!
> 
> I've got the following error report while running the syzkaller fuzzer.
> 
> ep0_write() doesn't check the length, so a user can cause an
> out-of-bounds with both size and data controlled.
> There's a comment which says "IN DATA+STATUS caller makes len <=
> wLength". While I'm not exactly sure what that means, the length seems
> to be passed unmodified directly from dev_config().

You're right about the comment being misleading.  It looks like 
somebody forgot to actually do the check.

> This doesn't seem to be a critical security issue since gadgetfs can't
> be mounted from a user namespace.
> 
> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
> 
> ==
> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
> 88003c47e160
> 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
>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
>  81f96828 813fb4a0 88003b6eadc0 88003c107738
> Call Trace:
>  [< inline >] __dump_stack lib/dump_stack.c:15
>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
>  [< inline >] print_address_description mm/kasan/report.c:197
>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
>  [] 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
>  [] dev_config+0x86f/0x1190
> drivers/usb/gadget/legacy/inode.c:1759
>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
>  [< inline >] SYSC_write fs/read_write.c:607
>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2

How does this patch work out?

Alan Stern



Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
===
--- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
+++ usb-4.x/drivers/usb/gadget/legacy/inode.c
@@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
/* data and/or status stage for control request */
} else if (dev->state == STATE_DEV_SETUP) {
 
-   /* IN DATA+STATUS caller makes len <= wLength */
+   len = min(len, (size_t) dev->setup_wLength);
if (dev->setup_in) {
retval = setup_req (dev->gadget->ep0, dev->req, len);
if (retval == 0) {

Re: net/gadget: slab-out-of-bounds write in dev_config

2016-12-06 Thread Alan Stern 
On Tue, 6 Dec 2016, Andrey Konovalov wrote:

> Hi!
> 
> I've got the following error report while running the syzkaller fuzzer.
> 
> ep0_write() doesn't check the length, so a user can cause an
> out-of-bounds with both size and data controlled.
> There's a comment which says "IN DATA+STATUS caller makes len <=
> wLength". While I'm not exactly sure what that means, the length seems
> to be passed unmodified directly from dev_config().

You're right about the comment being misleading.  It looks like 
somebody forgot to actually do the check.

> This doesn't seem to be a critical security issue since gadgetfs can't
> be mounted from a user namespace.
> 
> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).
> 
> ==
> BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
> 88003c47e160
> 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
>  88003c107ad8 81f96aba 3dc11ef0 110007820eee
>  ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
>  81f96828 813fb4a0 88003b6eadc0 88003c107738
> Call Trace:
>  [< inline >] __dump_stack lib/dump_stack.c:15
>  [] dump_stack+0x292/0x398 lib/dump_stack.c:51
>  [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
>  [< inline >] print_address_description mm/kasan/report.c:197
>  [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
>  [] kasan_report+0x35/0x40 mm/kasan/report.c:306
>  [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
>  [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
>  [] 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
>  [] dev_config+0x86f/0x1190
> drivers/usb/gadget/legacy/inode.c:1759
>  [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
>  [] vfs_write+0x170/0x4e0 fs/read_write.c:560
>  [< inline >] SYSC_write fs/read_write.c:607
>  [] SyS_write+0xfb/0x230 fs/read_write.c:599
>  [] entry_SYSCALL_64_fastpath+0x1f/0xc2

How does this patch work out?

Alan Stern



Index: usb-4.x/drivers/usb/gadget/legacy/inode.c
===
--- usb-4.x.orig/drivers/usb/gadget/legacy/inode.c
+++ usb-4.x/drivers/usb/gadget/legacy/inode.c
@@ -1126,7 +1126,7 @@ ep0_write (struct file *fd, const char _
/* data and/or status stage for control request */
} else if (dev->state == STATE_DEV_SETUP) {
 
-   /* IN DATA+STATUS caller makes len <= wLength */
+   len = min(len, (size_t) dev->setup_wLength);
if (dev->setup_in) {
retval = setup_req (dev->gadget->ep0, dev->req, len);
if (retval == 0) {

net/gadget: slab-out-of-bounds write in dev_config

2016-12-06 Thread Andrey Konovalov 
Hi!

I've got the following error report while running the syzkaller fuzzer.

ep0_write() doesn't check the length, so a user can cause an
out-of-bounds with both size and data controlled.
There's a comment which says "IN DATA+STATUS caller makes len <=
wLength". While I'm not exactly sure what that means, the length seems
to be passed unmodified directly from dev_config().

This doesn't seem to be a critical security issue since gadgetfs can't
be mounted from a user namespace.

On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).

==
BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
88003c47e160
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
 88003c107ad8 81f96aba 3dc11ef0 110007820eee
 ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
 81f96828 813fb4a0 88003b6eadc0 88003c107738
Call Trace:
 [< inline >] __dump_stack lib/dump_stack.c:15
 [] dump_stack+0x292/0x398 lib/dump_stack.c:51
 [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
 [< inline >] print_address_description mm/kasan/report.c:197
 [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
 [] kasan_report+0x35/0x40 mm/kasan/report.c:306
 [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
 [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
 [] 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
 [] dev_config+0x86f/0x1190
drivers/usb/gadget/legacy/inode.c:1759
 [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
 [] vfs_write+0x170/0x4e0 fs/read_write.c:560
 [< inline >] SYSC_write fs/read_write.c:607
 [] SyS_write+0xfb/0x230 fs/read_write.c:599
 [] entry_SYSCALL_64_fastpath+0x1f/0xc2
Object at 88003c47e038, in cache kmalloc-1024 size: 1024
Allocated:
PID = 4565
 [   43.417154] [] save_stack_trace+0x16/0x20
arch/x86/kernel/stacktrace.c:57
 [   43.417154] [] save_stack+0x43/0xd0 mm/kasan/kasan.c:495
 [   43.417154] [< inline >] set_track mm/kasan/kasan.c:507
 [   43.417154] [] kasan_kmalloc+0xad/0xe0
mm/kasan/kasan.c:598
 [   43.417154] [] kmem_cache_alloc_trace+0x82/0x270
mm/slub.c:2735
 [   43.417154] [< inline >] kmalloc include/linux/slab.h:490
 [   43.417154] [< inline >] kzalloc include/linux/slab.h:636
 [   43.417154] [< inline >] dev_new
drivers/usb/gadget/legacy/inode.c:170
 [   43.417154] [] gadgetfs_fill_super+0x24a/0x540
drivers/usb/gadget/legacy/inode.c:1987
 [   43.417154] [] mount_single+0xf1/0x160 fs/super.c:1146
 [   43.417154] [] gadgetfs_mount+0x2c/0x40
drivers/usb/gadget/legacy/inode.c:2013
 [   43.417154] [] mount_fs+0x97/0x2e0 fs/super.c:1177
 [   43.417154] [] vfs_kern_mount.part.24+0x67/0x2f0
fs/namespace.c:954
 [   43.417154] [< inline >] vfs_kern_mount fs/namespace.c:2433
 [   43.417154] [< inline >] do_new_mount fs/namespace.c:2436
 [   43.417154] [] do_mount+0x418/0x2da0 fs/namespace.c:2758
 [   43.417154] [< inline >] SYSC_mount fs/namespace.c:2974
 [   43.417154] [] SyS_mount+0xab/0x120 fs/namespace.c:2951
 [   43.417154] [] entry_SYSCALL_64_fastpath+0x1f/0xc2
Freed:
PID = 0
(stack is not available)
Memory state around the buggy address:
 88003c47e100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 88003c47e180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>88003c47e200: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
   ^
 88003c47e280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 88003c47e300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==

net/gadget: slab-out-of-bounds write in dev_config

2016-12-06 Thread Andrey Konovalov 
Hi!

I've got the following error report while running the syzkaller fuzzer.

ep0_write() doesn't check the length, so a user can cause an
out-of-bounds with both size and data controlled.
There's a comment which says "IN DATA+STATUS caller makes len <=
wLength". While I'm not exactly sure what that means, the length seems
to be passed unmodified directly from dev_config().

This doesn't seem to be a critical security issue since gadgetfs can't
be mounted from a user namespace.

On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dec 2).

==
BUG: KASAN: slab-out-of-bounds in dev_config+0x86f/0x1190 at addr
88003c47e160
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
 88003c107ad8 81f96aba 3dc11ef0 110007820eee
 ed0007820ee6 88003dc11f00 41b58ab3 8598b4c8
 81f96828 813fb4a0 88003b6eadc0 88003c107738
Call Trace:
 [< inline >] __dump_stack lib/dump_stack.c:15
 [] dump_stack+0x292/0x398 lib/dump_stack.c:51
 [] kasan_object_err+0x1c/0x70 mm/kasan/report.c:159
 [< inline >] print_address_description mm/kasan/report.c:197
 [] kasan_report_error+0x1f0/0x4e0 mm/kasan/report.c:286
 [] kasan_report+0x35/0x40 mm/kasan/report.c:306
 [< inline >] check_memory_region_inline mm/kasan/kasan.c:308
 [] check_memory_region+0x139/0x190 mm/kasan/kasan.c:315
 [] 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
 [] dev_config+0x86f/0x1190
drivers/usb/gadget/legacy/inode.c:1759
 [] __vfs_write+0x5d5/0x760 fs/read_write.c:510
 [] vfs_write+0x170/0x4e0 fs/read_write.c:560
 [< inline >] SYSC_write fs/read_write.c:607
 [] SyS_write+0xfb/0x230 fs/read_write.c:599
 [] entry_SYSCALL_64_fastpath+0x1f/0xc2
Object at 88003c47e038, in cache kmalloc-1024 size: 1024
Allocated:
PID = 4565
 [   43.417154] [] save_stack_trace+0x16/0x20
arch/x86/kernel/stacktrace.c:57
 [   43.417154] [] save_stack+0x43/0xd0 mm/kasan/kasan.c:495
 [   43.417154] [< inline >] set_track mm/kasan/kasan.c:507
 [   43.417154] [] kasan_kmalloc+0xad/0xe0
mm/kasan/kasan.c:598
 [   43.417154] [] kmem_cache_alloc_trace+0x82/0x270
mm/slub.c:2735
 [   43.417154] [< inline >] kmalloc include/linux/slab.h:490
 [   43.417154] [< inline >] kzalloc include/linux/slab.h:636
 [   43.417154] [< inline >] dev_new
drivers/usb/gadget/legacy/inode.c:170
 [   43.417154] [] gadgetfs_fill_super+0x24a/0x540
drivers/usb/gadget/legacy/inode.c:1987
 [   43.417154] [] mount_single+0xf1/0x160 fs/super.c:1146
 [   43.417154] [] gadgetfs_mount+0x2c/0x40
drivers/usb/gadget/legacy/inode.c:2013
 [   43.417154] [] mount_fs+0x97/0x2e0 fs/super.c:1177
 [   43.417154] [] vfs_kern_mount.part.24+0x67/0x2f0
fs/namespace.c:954
 [   43.417154] [< inline >] vfs_kern_mount fs/namespace.c:2433
 [   43.417154] [< inline >] do_new_mount fs/namespace.c:2436
 [   43.417154] [] do_mount+0x418/0x2da0 fs/namespace.c:2758
 [   43.417154] [< inline >] SYSC_mount fs/namespace.c:2974
 [   43.417154] [] SyS_mount+0xab/0x120 fs/namespace.c:2951
 [   43.417154] [] entry_SYSCALL_64_fastpath+0x1f/0xc2
Freed:
PID = 0
(stack is not available)
Memory state around the buggy address:
 88003c47e100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 88003c47e180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>88003c47e200: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
   ^
 88003c47e280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 88003c47e300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==