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* Re: [PATCH] floppy: fix usercopy direction
       [not found] <20190326220348.61172-1-jannh@google.com>
@ 2019-08-09 13:36 ` Alexander Popov
  2019-08-09 13:41   ` Jens Axboe
                     ` (2 more replies)
  0 siblings, 3 replies; 8+ messages in thread
From: Alexander Popov @ 2019-08-09 13:36 UTC (permalink / raw)
  To: Jann Horn, Jens Axboe
  Cc: Jiri Kosina, linux-block, linux-kernel, Al Viro, Mukesh Ojha,
	kernel-hardening, Denis Efremov, Julia Lawall, Gilles Muller,
	Nicolas Palix, Michal Marek, cocci

Hello everyone!

On 27.03.2019 1:03, Jann Horn wrote:
> As sparse points out, these two copy_from_user() should actually be
> copy_to_user().

I've spent some time on these bugs, but it turned out that they are already public.

I think Jann's patch is lost, it is not applied to the mainline.
So I add a new floppy maintainer Denis Efremov to CC.

These bugs on x86_64 cause memset for the userspace memory from the kernelspace.
That is funny:
 - access_ok for the copy_from_user source (2nd argument) returns zero;
 - copy_from_user tries to erase the destination (1st argument);
 - but the destination is in the userspace instead of kernelspace.

So we have:
[   40.937098] BUG: unable to handle page fault for address: 0000000041414242
[   40.938714] #PF: supervisor write access in kernel mode
[   40.939951] #PF: error_code(0x0002) - not-present page
[   40.941121] PGD 7963f067 P4D 7963f067 PUD 0
[   40.942107] Oops: 0002 [#1] SMP NOPTI
[   40.942968] CPU: 0 PID: 292 Comm: d Not tainted 5.3.0-rc3+ #7
[   40.944288] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
Ubuntu-1.8.2-1ubuntu1 04/01/2014
[   40.946478] RIP: 0010:__memset+0x24/0x30
[   40.947394] Code: 90 90 90 90 90 90 0f 1f 44 00 00 49 89 f9 48 89 d1 83 e2 07
48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 <f3> 48 ab 89
d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3
[   40.951721] RSP: 0018:ffffc900003dbd58 EFLAGS: 00010206
[   40.952941] RAX: 0000000000000000 RBX: 0000000000000034 RCX: 0000000000000006
[   40.954592] RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000041414242
[   40.956169] RBP: 0000000041414242 R08: ffffffff8200bd80 R09: 0000000041414242
[   40.957753] R10: 0000000000121806 R11: ffff88807da28ab0 R12: ffffc900003dbd7c
[   40.959407] R13: 0000000000000001 R14: 0000000041414242 R15: 0000000041414242
[   40.961062] FS:  00007f91115c4440(0000) GS:ffff88807da00000(0000)
knlGS:0000000000000000
[   40.962603] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   40.963695] CR2: 0000000041414242 CR3: 000000007c584000 CR4: 00000000000006f0
[   40.965004] Call Trace:
[   40.965459]  _copy_from_user+0x51/0x60
[   40.966141]  compat_getdrvstat+0x124/0x170
[   40.966781]  fd_compat_ioctl+0x69c/0x6d0
[   40.967423]  ? selinux_file_ioctl+0x16f/0x210
[   40.968117]  compat_blkdev_ioctl+0x21d/0x8f0
[   40.968864]  __x32_compat_sys_ioctl+0x99/0x250
[   40.969659]  do_syscall_64+0x4a/0x110
[   40.970337]  entry_SYSCALL_64_after_hwframe+0x44/0xa9


I haven't found a way to exploit it.

> Fixes: 229b53c9bf4e ("take floppy compat ioctls to sodding floppy.c")
> Cc: stable@vger.kernel.org
> Signed-off-by: Jann Horn <jannh@google.com>
> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
> ---
> compile-tested only

Acked-by: Alexander Popov <alex.popov@linux.com>

>  drivers/block/floppy.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
> index 95f608d1a098..8c641245ff12 100644
> --- a/drivers/block/floppy.c
> +++ b/drivers/block/floppy.c
> @@ -3749,7 +3749,7 @@ static int compat_getdrvprm(int drive,
>  	v.native_format = UDP->native_format;
>  	mutex_unlock(&floppy_mutex);
>  
> -	if (copy_from_user(arg, &v, sizeof(struct compat_floppy_drive_params)))
> +	if (copy_to_user(arg, &v, sizeof(struct compat_floppy_drive_params)))
>  		return -EFAULT;
>  	return 0;
>  }
> @@ -3785,7 +3785,7 @@ static int compat_getdrvstat(int drive, bool poll,
>  	v.bufblocks = UDRS->bufblocks;
>  	mutex_unlock(&floppy_mutex);
>  
> -	if (copy_from_user(arg, &v, sizeof(struct compat_floppy_drive_struct)))
> +	if (copy_to_user(arg, &v, sizeof(struct compat_floppy_drive_struct)))
>  		return -EFAULT;
>  	return 0;
>  Eintr:
> 

I also wrote a coccinelle rule for detecting similar bugs (adding coccinelle
experts to CC).


virtual report

@cfu@
identifier f;
type t;
identifier v;
position decl_p;
position copy_p;
@@

f(..., t v@decl_p, ...)
{
<+...
copy_from_user@copy_p(v, ...)
...+>
}

@script:python@
f << cfu.f;
t << cfu.t;
v << cfu.v;
decl_p << cfu.decl_p;
copy_p << cfu.copy_p;
@@

if '__user' in t:
  msg0 = "function \"" + f + "\" has arg \"" + v + "\" of type \"" + t + "\""
  coccilib.report.print_report(decl_p[0], msg0)
  msg1 = "copy_from_user uses \"" + v + "\" as the destination. What a shame!\n"
  coccilib.report.print_report(copy_p[0], msg1)


The rule output:

./drivers/block/floppy.c:3756:49-52: function "compat_getdrvprm" has arg "arg"
of type "struct compat_floppy_drive_params __user *"
./drivers/block/floppy.c:3783:5-19: copy_from_user uses "arg" as the
destination. What a shame!

./drivers/block/floppy.c:3789:49-52: function "compat_getdrvstat" has arg "arg"
of type "struct compat_floppy_drive_struct __user *"
./drivers/block/floppy.c:3819:5-19: copy_from_user uses "arg" as the
destination. What a shame!


Best regards,
Alexander

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH] floppy: fix usercopy direction
  2019-08-09 13:36 ` [PATCH] floppy: fix usercopy direction Alexander Popov
@ 2019-08-09 13:41   ` Jens Axboe
  2019-08-09 13:43     ` Denis Efremov
  2019-08-09 13:56   ` Julia Lawall
  2019-08-13  7:50   ` Markus Elfring
  2 siblings, 1 reply; 8+ messages in thread
From: Jens Axboe @ 2019-08-09 13:41 UTC (permalink / raw)
  To: alex.popov, Jann Horn
  Cc: Jiri Kosina, linux-block, linux-kernel, Al Viro, Mukesh Ojha,
	kernel-hardening, Denis Efremov, Julia Lawall, Gilles Muller,
	Nicolas Palix, Michal Marek, cocci

On 8/9/19 6:36 AM, Alexander Popov wrote:
> Hello everyone!
> 
> On 27.03.2019 1:03, Jann Horn wrote:
>> As sparse points out, these two copy_from_user() should actually be
>> copy_to_user().
> 
> I've spent some time on these bugs, but it turned out that they are already public.
> 
> I think Jann's patch is lost, it is not applied to the mainline.
> So I add a new floppy maintainer Denis Efremov to CC.

Looks like it got lost indeed, I will just apply this one directly for
5.4.

-- 
Jens Axboe


^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH] floppy: fix usercopy direction
  2019-08-09 13:41   ` Jens Axboe
@ 2019-08-09 13:43     ` Denis Efremov
  0 siblings, 0 replies; 8+ messages in thread
From: Denis Efremov @ 2019-08-09 13:43 UTC (permalink / raw)
  To: Jens Axboe, alex.popov, Jann Horn
  Cc: Jiri Kosina, linux-block, linux-kernel, Al Viro, Mukesh Ojha,
	kernel-hardening, Julia Lawall, Gilles Muller, Nicolas Palix,
	Michal Marek, cocci

>> So I add a new floppy maintainer Denis Efremov to CC.
> 
> Looks like it got lost indeed, I will just apply this one directly for
> 5.4.
> 

Thank you!

Denis

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH] floppy: fix usercopy direction
  2019-08-09 13:36 ` [PATCH] floppy: fix usercopy direction Alexander Popov
  2019-08-09 13:41   ` Jens Axboe
@ 2019-08-09 13:56   ` Julia Lawall
  2019-08-09 15:05     ` Alexander Popov
  2019-08-13  7:50   ` Markus Elfring
  2 siblings, 1 reply; 8+ messages in thread
From: Julia Lawall @ 2019-08-09 13:56 UTC (permalink / raw)
  To: Alexander Popov
  Cc: Jann Horn, Jens Axboe, Jiri Kosina, linux-block, linux-kernel,
	Al Viro, Mukesh Ojha, kernel-hardening, Denis Efremov,
	Julia Lawall, Gilles Muller, Nicolas Palix, Michal Marek, cocci



On Fri, 9 Aug 2019, Alexander Popov wrote:

> Hello everyone!
>
> On 27.03.2019 1:03, Jann Horn wrote:
> > As sparse points out, these two copy_from_user() should actually be
> > copy_to_user().
>
> I've spent some time on these bugs, but it turned out that they are already public.
>
> I think Jann's patch is lost, it is not applied to the mainline.
> So I add a new floppy maintainer Denis Efremov to CC.
>
> These bugs on x86_64 cause memset for the userspace memory from the kernelspace.
> That is funny:
>  - access_ok for the copy_from_user source (2nd argument) returns zero;
>  - copy_from_user tries to erase the destination (1st argument);
>  - but the destination is in the userspace instead of kernelspace.
>
> So we have:
> [   40.937098] BUG: unable to handle page fault for address: 0000000041414242
> [   40.938714] #PF: supervisor write access in kernel mode
> [   40.939951] #PF: error_code(0x0002) - not-present page
> [   40.941121] PGD 7963f067 P4D 7963f067 PUD 0
> [   40.942107] Oops: 0002 [#1] SMP NOPTI
> [   40.942968] CPU: 0 PID: 292 Comm: d Not tainted 5.3.0-rc3+ #7
> [   40.944288] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> Ubuntu-1.8.2-1ubuntu1 04/01/2014
> [   40.946478] RIP: 0010:__memset+0x24/0x30
> [   40.947394] Code: 90 90 90 90 90 90 0f 1f 44 00 00 49 89 f9 48 89 d1 83 e2 07
> 48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 <f3> 48 ab 89
> d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3
> [   40.951721] RSP: 0018:ffffc900003dbd58 EFLAGS: 00010206
> [   40.952941] RAX: 0000000000000000 RBX: 0000000000000034 RCX: 0000000000000006
> [   40.954592] RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000041414242
> [   40.956169] RBP: 0000000041414242 R08: ffffffff8200bd80 R09: 0000000041414242
> [   40.957753] R10: 0000000000121806 R11: ffff88807da28ab0 R12: ffffc900003dbd7c
> [   40.959407] R13: 0000000000000001 R14: 0000000041414242 R15: 0000000041414242
> [   40.961062] FS:  00007f91115c4440(0000) GS:ffff88807da00000(0000)
> knlGS:0000000000000000
> [   40.962603] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [   40.963695] CR2: 0000000041414242 CR3: 000000007c584000 CR4: 00000000000006f0
> [   40.965004] Call Trace:
> [   40.965459]  _copy_from_user+0x51/0x60
> [   40.966141]  compat_getdrvstat+0x124/0x170
> [   40.966781]  fd_compat_ioctl+0x69c/0x6d0
> [   40.967423]  ? selinux_file_ioctl+0x16f/0x210
> [   40.968117]  compat_blkdev_ioctl+0x21d/0x8f0
> [   40.968864]  __x32_compat_sys_ioctl+0x99/0x250
> [   40.969659]  do_syscall_64+0x4a/0x110
> [   40.970337]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
>
>
> I haven't found a way to exploit it.
>
> > Fixes: 229b53c9bf4e ("take floppy compat ioctls to sodding floppy.c")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Jann Horn <jannh@google.com>
> > Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
> > ---
> > compile-tested only
>
> Acked-by: Alexander Popov <alex.popov@linux.com>
>
> >  drivers/block/floppy.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
> > index 95f608d1a098..8c641245ff12 100644
> > --- a/drivers/block/floppy.c
> > +++ b/drivers/block/floppy.c
> > @@ -3749,7 +3749,7 @@ static int compat_getdrvprm(int drive,
> >  	v.native_format = UDP->native_format;
> >  	mutex_unlock(&floppy_mutex);
> >
> > -	if (copy_from_user(arg, &v, sizeof(struct compat_floppy_drive_params)))
> > +	if (copy_to_user(arg, &v, sizeof(struct compat_floppy_drive_params)))
> >  		return -EFAULT;
> >  	return 0;
> >  }
> > @@ -3785,7 +3785,7 @@ static int compat_getdrvstat(int drive, bool poll,
> >  	v.bufblocks = UDRS->bufblocks;
> >  	mutex_unlock(&floppy_mutex);
> >
> > -	if (copy_from_user(arg, &v, sizeof(struct compat_floppy_drive_struct)))
> > +	if (copy_to_user(arg, &v, sizeof(struct compat_floppy_drive_struct)))
> >  		return -EFAULT;
> >  	return 0;
> >  Eintr:
> >
>
> I also wrote a coccinelle rule for detecting similar bugs (adding coccinelle
> experts to CC).
>
>
> virtual report
>
> @cfu@

You can replace the above line with @cfu exists@.  You want to find the
existence of such a call, not ensure that the call occurs on every
control-flow path, which is the default.

Do you want this rule to go into the kernel?

julia

> identifier f;
> type t;
> identifier v;
> position decl_p;
> position copy_p;
> @@
>
> f(..., t v@decl_p, ...)
> {
> <+...
> copy_from_user@copy_p(v, ...)
> ...+>
> }
>
> @script:python@
> f << cfu.f;
> t << cfu.t;
> v << cfu.v;
> decl_p << cfu.decl_p;
> copy_p << cfu.copy_p;
> @@
>
> if '__user' in t:
>   msg0 = "function \"" + f + "\" has arg \"" + v + "\" of type \"" + t + "\""
>   coccilib.report.print_report(decl_p[0], msg0)
>   msg1 = "copy_from_user uses \"" + v + "\" as the destination. What a shame!\n"
>   coccilib.report.print_report(copy_p[0], msg1)
>
>
> The rule output:
>
> ./drivers/block/floppy.c:3756:49-52: function "compat_getdrvprm" has arg "arg"
> of type "struct compat_floppy_drive_params __user *"
> ./drivers/block/floppy.c:3783:5-19: copy_from_user uses "arg" as the
> destination. What a shame!
>
> ./drivers/block/floppy.c:3789:49-52: function "compat_getdrvstat" has arg "arg"
> of type "struct compat_floppy_drive_struct __user *"
> ./drivers/block/floppy.c:3819:5-19: copy_from_user uses "arg" as the
> destination. What a shame!
>
>
> Best regards,
> Alexander
>

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH] floppy: fix usercopy direction
  2019-08-09 13:56   ` Julia Lawall
@ 2019-08-09 15:05     ` Alexander Popov
  2019-08-12 10:00       ` Markus Elfring
  2019-08-12 10:25       ` [PATCH] " Julia Lawall
  0 siblings, 2 replies; 8+ messages in thread
From: Alexander Popov @ 2019-08-09 15:05 UTC (permalink / raw)
  To: Julia Lawall, Jann Horn
  Cc: Jens Axboe, Jiri Kosina, linux-block, linux-kernel, Al Viro,
	Mukesh Ojha, kernel-hardening, Denis Efremov, Gilles Muller,
	Nicolas Palix, Michal Marek, cocci

On 09.08.2019 16:56, Julia Lawall wrote:
> On Fri, 9 Aug 2019, Alexander Popov wrote:
>> On 27.03.2019 1:03, Jann Horn wrote:
>>> As sparse points out, these two copy_from_user() should actually be
>>> copy_to_user().
>>
>> I also wrote a coccinelle rule for detecting similar bugs (adding coccinelle
>> experts to CC).
>>
>>
>> virtual report
>>
>> @cfu@
> 
> You can replace the above line with @cfu exists@.  You want to find the
> existence of such a call, not ensure that the call occurs on every
> control-flow path, which is the default.

Thanks Julia, I see `exists` allows to drop `<+ +>`, right?

> Do you want this rule to go into the kernel?

It turned out that sparse already can find these bugs.
Is this rule useful anyway? If so, I can prepare a patch.

>> identifier f;
>> type t;
>> identifier v;
>> position decl_p;
>> position copy_p;
>> @@
>>
>> f(..., t v@decl_p, ...)
>> {
>> <+...
>> copy_from_user@copy_p(v, ...)
>> ...+>
>> }
>>
>> @script:python@
>> f << cfu.f;
>> t << cfu.t;
>> v << cfu.v;
>> decl_p << cfu.decl_p;
>> copy_p << cfu.copy_p;
>> @@
>>
>> if '__user' in t:
>>   msg0 = "function \"" + f + "\" has arg \"" + v + "\" of type \"" + t + "\""
>>   coccilib.report.print_report(decl_p[0], msg0)
>>   msg1 = "copy_from_user uses \"" + v + "\" as the destination. What a shame!\n"
>>   coccilib.report.print_report(copy_p[0], msg1)
>>
>>
>> The rule output:
>>
>> ./drivers/block/floppy.c:3756:49-52: function "compat_getdrvprm" has arg "arg"
>> of type "struct compat_floppy_drive_params __user *"
>> ./drivers/block/floppy.c:3783:5-19: copy_from_user uses "arg" as the
>> destination. What a shame!
>>
>> ./drivers/block/floppy.c:3789:49-52: function "compat_getdrvstat" has arg "arg"
>> of type "struct compat_floppy_drive_struct __user *"
>> ./drivers/block/floppy.c:3819:5-19: copy_from_user uses "arg" as the
>> destination. What a shame!

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: floppy: fix usercopy direction
  2019-08-09 15:05     ` Alexander Popov
@ 2019-08-12 10:00       ` Markus Elfring
  2019-08-12 10:25       ` [PATCH] " Julia Lawall
  1 sibling, 0 replies; 8+ messages in thread
From: Markus Elfring @ 2019-08-12 10:00 UTC (permalink / raw)
  To: Alexander Popov, Jann Horn, Julia Lawall, kernel-janitors, cocci
  Cc: linux-kernel, linux-block, kernel-hardening, Al Viro,
	Denis Efremov, Gilles Muller, Jens Axboe, Jiri Kosina,
	Michal Marek, Mukesh Ojha, Nicolas Palix

> …, I see `exists` allows to drop `<+ +>`, right?

I would interpret the combination of such SmPL specifications in a different way.


> It turned out that sparse already can find these bugs.

This is generally nice, isn't it?


> Is this rule useful anyway?

I hope so.

Can scripts for the semantic patch language help any more?


> If so, I can prepare a patch.

Would you like to take corresponding adjustments into account?

Regards,
Markus

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH] floppy: fix usercopy direction
  2019-08-09 15:05     ` Alexander Popov
  2019-08-12 10:00       ` Markus Elfring
@ 2019-08-12 10:25       ` " Julia Lawall
  1 sibling, 0 replies; 8+ messages in thread
From: Julia Lawall @ 2019-08-12 10:25 UTC (permalink / raw)
  To: Alexander Popov
  Cc: Julia Lawall, Jann Horn, Jens Axboe, Jiri Kosina, linux-block,
	linux-kernel, Al Viro, Mukesh Ojha, kernel-hardening,
	Denis Efremov, Gilles Muller, Nicolas Palix, Michal Marek, cocci


On Fri, 9 Aug 2019, Alexander Popov wrote:

> On 09.08.2019 16:56, Julia Lawall wrote:
> > On Fri, 9 Aug 2019, Alexander Popov wrote:
> >> On 27.03.2019 1:03, Jann Horn wrote:
> >>> As sparse points out, these two copy_from_user() should actually be
> >>> copy_to_user().
> >>
> >> I also wrote a coccinelle rule for detecting similar bugs (adding coccinelle
> >> experts to CC).
> >>
> >>
> >> virtual report
> >>
> >> @cfu@
> >
> > You can replace the above line with @cfu exists@.  You want to find the
> > existence of such a call, not ensure that the call occurs on every
> > control-flow path, which is the default.
>
> Thanks Julia, I see `exists` allows to drop `<+ +>`, right?

Exists is more efficient when it is possible.  It just finds the existence
of a path that has the property rather than collecting information about
all paths.  It is related to <+... ...+> because for that there has to
exist at least one match.  You could probably do something like

... when any
copy_from_user
... when any

Then with exists you will consider each call one at a time.

>
> > Do you want this rule to go into the kernel?
>
> It turned out that sparse already can find these bugs.

If sparse is already doing this, then perhaps that's sufficient.  Someone
just has to be running it :)

julia

> Is this rule useful anyway? If so, I can prepare a patch.
>
> >> identifier f;
> >> type t;
> >> identifier v;
> >> position decl_p;
> >> position copy_p;
> >> @@
> >>
> >> f(..., t v@decl_p, ...)
> >> {
> >> <+...
> >> copy_from_user@copy_p(v, ...)
> >> ...+>
> >> }
> >>
> >> @script:python@
> >> f << cfu.f;
> >> t << cfu.t;
> >> v << cfu.v;
> >> decl_p << cfu.decl_p;
> >> copy_p << cfu.copy_p;
> >> @@
> >>
> >> if '__user' in t:
> >>   msg0 = "function \"" + f + "\" has arg \"" + v + "\" of type \"" + t + "\""
> >>   coccilib.report.print_report(decl_p[0], msg0)
> >>   msg1 = "copy_from_user uses \"" + v + "\" as the destination. What a shame!\n"
> >>   coccilib.report.print_report(copy_p[0], msg1)
> >>
> >>
> >> The rule output:
> >>
> >> ./drivers/block/floppy.c:3756:49-52: function "compat_getdrvprm" has arg "arg"
> >> of type "struct compat_floppy_drive_params __user *"
> >> ./drivers/block/floppy.c:3783:5-19: copy_from_user uses "arg" as the
> >> destination. What a shame!
> >>
> >> ./drivers/block/floppy.c:3789:49-52: function "compat_getdrvstat" has arg "arg"
> >> of type "struct compat_floppy_drive_struct __user *"
> >> ./drivers/block/floppy.c:3819:5-19: copy_from_user uses "arg" as the
> >> destination. What a shame!
>

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: floppy: fix usercopy direction
  2019-08-09 13:36 ` [PATCH] floppy: fix usercopy direction Alexander Popov
  2019-08-09 13:41   ` Jens Axboe
  2019-08-09 13:56   ` Julia Lawall
@ 2019-08-13  7:50   ` Markus Elfring
  2 siblings, 0 replies; 8+ messages in thread
From: Markus Elfring @ 2019-08-13  7:50 UTC (permalink / raw)
  To: Alexander Popov, cocci
  Cc: kernel-hardening, linux-block, linux-kernel, Al Viro,
	Denis Efremov, Gilles Muller, Jann Horn, Jens Axboe, Jiri Kosina,
	Julia Lawall, Michal Marek, Mukesh Ojha, Nicolas Palix

> @script:python@
> f << cfu.f;
> t << cfu.t;
> v << cfu.v;
> decl_p << cfu.decl_p;
> copy_p << cfu.copy_p;
> @@
>
> if '__user' in t:

Can this check be specified as a constraint for a metavariable
in the initial SmPL rule?
Would you like to move it to an other place?

Regards,
Markus

^ permalink raw reply	[flat|nested] 8+ messages in thread

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Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <20190326220348.61172-1-jannh@google.com>
2019-08-09 13:36 ` [PATCH] floppy: fix usercopy direction Alexander Popov
2019-08-09 13:41   ` Jens Axboe
2019-08-09 13:43     ` Denis Efremov
2019-08-09 13:56   ` Julia Lawall
2019-08-09 15:05     ` Alexander Popov
2019-08-12 10:00       ` Markus Elfring
2019-08-12 10:25       ` [PATCH] " Julia Lawall
2019-08-13  7:50   ` Markus Elfring

Kernel-hardening archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/kernel-hardening/0 kernel-hardening/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 kernel-hardening kernel-hardening/ https://lore.kernel.org/kernel-hardening \
		kernel-hardening@lists.openwall.com
	public-inbox-index kernel-hardening

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/com.openwall.lists.kernel-hardening


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git