All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] um: ubd: Fix crash from option parsing
@ 2021-01-19 18:19 ` Paul Lawrence
  0 siblings, 0 replies; 8+ messages in thread
From: Paul Lawrence @ 2021-01-19 18:19 UTC (permalink / raw)
  To: Jeff Dike, Richard Weinberger, Anton Ivanov,
	Gabriel Krisman Bertazi, Christopher Obbard, Paul Lawrence
  Cc: linux-um, linux-kernel

Below patch will cause NULL ptr dereferences if the optional filenames
are not present.

Fixes: ef3ba87cb7c9 (um: ubd: Set device serial attribute from cmdline)
Signed-off-by: Paul Lawrence <paullawrence@google.com>
---
 arch/um/drivers/ubd_kern.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 13b1fe694b90..704989088f28 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -371,15 +371,15 @@ static int ubd_setup_common(char *str, int *index_out, char **error_out)
 
 break_loop:
 	file = strsep(&str, ",:");
-	if (*file == '\0')
+	if (file && *file == '\0')
 		file = NULL;
 
 	backing_file = strsep(&str, ",:");
-	if (*backing_file == '\0')
+	if (backing_file && *backing_file == '\0')
 		backing_file = NULL;
 
 	serial = strsep(&str, ",:");
-	if (*serial == '\0')
+	if (serial && *serial == '\0')
 		serial = NULL;
 
 	if (backing_file && ubd_dev->no_cow) {
-- 
2.30.0.284.gd98b1dd5eaa7-goog


^ permalink raw reply related	[flat|nested] 8+ messages in thread
* [PATCH] um: ubd: Fix crash from option parsing
@ 2021-01-19 18:19 ` Paul Lawrence
  0 siblings, 0 replies; 8+ messages in thread
From: Paul Lawrence @ 2021-01-19 18:19 UTC (permalink / raw)
  To: Jeff Dike, Richard Weinberger, Anton Ivanov,
	Gabriel Krisman Bertazi, Christopher Obbard, Paul Lawrence
  Cc: linux-um, linux-kernel

Below patch will cause NULL ptr dereferences if the optional filenames
are not present.

Fixes: ef3ba87cb7c9 (um: ubd: Set device serial attribute from cmdline)
Signed-off-by: Paul Lawrence <paullawrence@google.com>
---
 arch/um/drivers/ubd_kern.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 13b1fe694b90..704989088f28 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -371,15 +371,15 @@ static int ubd_setup_common(char *str, int *index_out, char **error_out)
 
 break_loop:
 	file = strsep(&str, ",:");
-	if (*file == '\0')
+	if (file && *file == '\0')
 		file = NULL;
 
 	backing_file = strsep(&str, ",:");
-	if (*backing_file == '\0')
+	if (backing_file && *backing_file == '\0')
 		backing_file = NULL;
 
 	serial = strsep(&str, ",:");
-	if (*serial == '\0')
+	if (serial && *serial == '\0')
 		serial = NULL;
 
 	if (backing_file && ubd_dev->no_cow) {
-- 
2.30.0.284.gd98b1dd5eaa7-goog


_______________________________________________
linux-um mailing list
linux-um@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-um


^ permalink raw reply related	[flat|nested] 8+ messages in thread
* Re: [PATCH] um: ubd: Fix crash from option parsing
  2021-01-19 18:19 ` Paul Lawrence
@ 2021-01-19 18:35   ` Gabriel Krisman Bertazi
  -1 siblings, 0 replies; 8+ messages in thread
From: Gabriel Krisman Bertazi @ 2021-01-19 18:35 UTC (permalink / raw)
  To: Paul Lawrence
  Cc: Jeff Dike, Richard Weinberger, Anton Ivanov, Christopher Obbard,
	linux-um, linux-kernel

Paul Lawrence <paullawrence@google.com> writes:

> Below patch will cause NULL ptr dereferences if the optional filenames
> are not present.
>
> Fixes: ef3ba87cb7c9 (um: ubd: Set device serial attribute from cmdline)
> Signed-off-by: Paul Lawrence <paullawrence@google.com>

Looks good.

Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>

Totally unrelated, but it seems the original patch writes a "(null)"
string to the sysfs attribute, if no serial is defined.  I think we
should have a default serial UBDX in case the user didn't provide any.

Thanks,

> ---
>  arch/um/drivers/ubd_kern.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
> index 13b1fe694b90..704989088f28 100644
> --- a/arch/um/drivers/ubd_kern.c
> +++ b/arch/um/drivers/ubd_kern.c
> @@ -371,15 +371,15 @@ static int ubd_setup_common(char *str, int *index_out, char **error_out)
>  
>  break_loop:
>  	file = strsep(&str, ",:");
> -	if (*file == '\0')
> +	if (file && *file == '\0')
>  		file = NULL;
>  
>  	backing_file = strsep(&str, ",:");
> -	if (*backing_file == '\0')
> +	if (backing_file && *backing_file == '\0')
>  		backing_file = NULL;
>  
>  	serial = strsep(&str, ",:");
> -	if (*serial == '\0')
> +	if (serial && *serial == '\0')
>  		serial = NULL;
>  
>  	if (backing_file && ubd_dev->no_cow) {

-- 
Gabriel Krisman Bertazi

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] um: ubd: Fix crash from option parsing
@ 2021-01-19 18:35   ` Gabriel Krisman Bertazi
  0 siblings, 0 replies; 8+ messages in thread
From: Gabriel Krisman Bertazi @ 2021-01-19 18:35 UTC (permalink / raw)
  To: Paul Lawrence
  Cc: Richard Weinberger, Jeff Dike, linux-um, linux-kernel,
	Christopher Obbard, Anton Ivanov

Paul Lawrence <paullawrence@google.com> writes:

> Below patch will cause NULL ptr dereferences if the optional filenames
> are not present.
>
> Fixes: ef3ba87cb7c9 (um: ubd: Set device serial attribute from cmdline)
> Signed-off-by: Paul Lawrence <paullawrence@google.com>

Looks good.

Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>

Totally unrelated, but it seems the original patch writes a "(null)"
string to the sysfs attribute, if no serial is defined.  I think we
should have a default serial UBDX in case the user didn't provide any.

Thanks,

> ---
>  arch/um/drivers/ubd_kern.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
> index 13b1fe694b90..704989088f28 100644
> --- a/arch/um/drivers/ubd_kern.c
> +++ b/arch/um/drivers/ubd_kern.c
> @@ -371,15 +371,15 @@ static int ubd_setup_common(char *str, int *index_out, char **error_out)
>  
>  break_loop:
>  	file = strsep(&str, ",:");
> -	if (*file == '\0')
> +	if (file && *file == '\0')
>  		file = NULL;
>  
>  	backing_file = strsep(&str, ",:");
> -	if (*backing_file == '\0')
> +	if (backing_file && *backing_file == '\0')
>  		backing_file = NULL;
>  
>  	serial = strsep(&str, ",:");
> -	if (*serial == '\0')
> +	if (serial && *serial == '\0')
>  		serial = NULL;
>  
>  	if (backing_file && ubd_dev->no_cow) {

-- 
Gabriel Krisman Bertazi

_______________________________________________
linux-um mailing list
linux-um@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-um


^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] um: ubd: Fix crash from option parsing
  2021-01-19 18:19 ` Paul Lawrence
@ 2021-01-22  0:41   ` Hajime Tazaki
  -1 siblings, 0 replies; 8+ messages in thread
From: Hajime Tazaki @ 2021-01-22  0:41 UTC (permalink / raw)
  To: paullawrence
  Cc: jdike, richard, anton.ivanov, krisman, chris.obbard, linux-um,
	linux-kernel


Hello,

On Wed, 20 Jan 2021 03:19:45 +0900,
Paul Lawrence wrote:
> 
> Below patch will cause NULL ptr dereferences if the optional filenames
> are not present.
> 
> Fixes: ef3ba87cb7c9 (um: ubd: Set device serial attribute from cmdline)
> Signed-off-by: Paul Lawrence <paullawrence@google.com>

This was addressed/fixed by the below patch, though that one doesn't
the first "file" variable check.

http://lists.infradead.org/pipermail/linux-um/2020-December/000983.html

There was another attempt to fix (with the same diff), btw.

http://lists.infradead.org/pipermail/linux-um/2021-January/000998.html

It seems that the patch is already queued but not upstreamed yet.

-- Hajime

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] um: ubd: Fix crash from option parsing
@ 2021-01-22  0:41   ` Hajime Tazaki
  0 siblings, 0 replies; 8+ messages in thread
From: Hajime Tazaki @ 2021-01-22  0:41 UTC (permalink / raw)
  To: paullawrence
  Cc: richard, jdike, linux-um, linux-kernel, krisman, chris.obbard,
	anton.ivanov


Hello,

On Wed, 20 Jan 2021 03:19:45 +0900,
Paul Lawrence wrote:
> 
> Below patch will cause NULL ptr dereferences if the optional filenames
> are not present.
> 
> Fixes: ef3ba87cb7c9 (um: ubd: Set device serial attribute from cmdline)
> Signed-off-by: Paul Lawrence <paullawrence@google.com>

This was addressed/fixed by the below patch, though that one doesn't
the first "file" variable check.

http://lists.infradead.org/pipermail/linux-um/2020-December/000983.html

There was another attempt to fix (with the same diff), btw.

http://lists.infradead.org/pipermail/linux-um/2021-January/000998.html

It seems that the patch is already queued but not upstreamed yet.

-- Hajime

_______________________________________________
linux-um mailing list
linux-um@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-um


^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] um: ubd: Fix crash from option parsing
  2021-01-22  0:41   ` Hajime Tazaki
@ 2021-01-22 14:44     ` Paul Lawrence
  -1 siblings, 0 replies; 8+ messages in thread
From: Paul Lawrence @ 2021-01-22 14:44 UTC (permalink / raw)
  To: Hajime Tazaki
  Cc: jdike, richard, anton.ivanov, krisman, chris.obbard, linux-um,
	Linux kernel

> This was addressed/fixed by the below patch, though that one doesn't
> the first "file" variable check.

I don't believe the first file variable can in fact be NULL, so my check was
unnecessary. Pleased to see this has been fixed, we can abandon my patch now.

Paul

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] um: ubd: Fix crash from option parsing
@ 2021-01-22 14:44     ` Paul Lawrence
  0 siblings, 0 replies; 8+ messages in thread
From: Paul Lawrence @ 2021-01-22 14:44 UTC (permalink / raw)
  To: Hajime Tazaki
  Cc: richard, jdike, linux-um, Linux kernel, krisman, chris.obbard,
	anton.ivanov

> This was addressed/fixed by the below patch, though that one doesn't
> the first "file" variable check.

I don't believe the first file variable can in fact be NULL, so my check was
unnecessary. Pleased to see this has been fixed, we can abandon my patch now.

Paul

_______________________________________________
linux-um mailing list
linux-um@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-um


^ permalink raw reply	[flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-01-22 14:46 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-19 18:19 [PATCH] um: ubd: Fix crash from option parsing Paul Lawrence
2021-01-19 18:19 ` Paul Lawrence
2021-01-19 18:35 ` Gabriel Krisman Bertazi
2021-01-19 18:35   ` Gabriel Krisman Bertazi
2021-01-22  0:41 ` Hajime Tazaki
2021-01-22  0:41   ` Hajime Tazaki
2021-01-22 14:44   ` Paul Lawrence
2021-01-22 14:44     ` Paul Lawrence

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.