2023-09-20 14:51:49

by Philipp Stanner

[permalink] [raw]
Subject: [PATCH v3 2/5] kernel: kexec: copy user-array safely

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 <[email protected]>
Signed-off-by: Philipp Stanner <[email protected]>
Acked-by: Baoquan He <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: Zack Rusin <[email protected]>
---
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]));
if (IS_ERR(ksegments))
return PTR_ERR(ksegments);

--
2.41.0