diff mbox series

[v2,2/5] kernel: kexec: copy user-array safely

Message ID 31313a8a1dd1baf9dd3c21fbe8dd46b9e111f20c.1694202430.git.pstanner@redhat.com (mailing list archive)
State New, archived
Headers show
Series Introduce new wrappers to copy user-arrays | expand

Commit Message

Philipp Stanner Sept. 8, 2023, 7:59 p.m. UTC
Currently, there is no overflow-check with memdup_user().

Use the new function memdup_array_user() instead of memdup_user() for
duplicating the user-space array safely.

Suggested-by: David Airlie <airlied@redhat.com>
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
---
 kernel/kexec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Baoquan He Sept. 11, 2023, 12:25 a.m. UTC | #1
On 09/08/23 at 09:59pm, Philipp Stanner wrote:
> Currently, there is no overflow-check with memdup_user().
> 
> Use the new function memdup_array_user() instead of memdup_user() for
> duplicating the user-space array safely.
> 
> Suggested-by: David Airlie <airlied@redhat.com>
> Signed-off-by: Philipp Stanner <pstanner@redhat.com>
> ---
>  kernel/kexec.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/kexec.c b/kernel/kexec.c
> index 107f355eac10..8f35a5a42af8 100644
> --- a/kernel/kexec.c
> +++ b/kernel/kexec.c
> @@ -247,7 +247,7 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
>  		((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT))
>  		return -EINVAL;
>  
> -	ksegments = memdup_user(segments, nr_segments * sizeof(ksegments[0]));
> +	ksegments = memdup_array_user(segments, nr_segments, sizeof(ksegments[0]));

LGTM,

Acked-by: Baoquan He <bhe@redhat.com>

>  	if (IS_ERR(ksegments))
>  		return PTR_ERR(ksegments);
>  
> -- 
> 2.41.0
> 
> 
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
>
diff mbox series

Patch

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 107f355eac10..8f35a5a42af8 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -247,7 +247,7 @@  SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
 		((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT))
 		return -EINVAL;
 
-	ksegments = memdup_user(segments, nr_segments * sizeof(ksegments[0]));
+	ksegments = memdup_array_user(segments, nr_segments, sizeof(ksegments[0]));
 	if (IS_ERR(ksegments))
 		return PTR_ERR(ksegments);