Forwarded: [PATCH] iommufd: Initialize pfn_reader in iopt_area_fill_domains()

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Subject: [PATCH] iommufd: Initialize pfn_reader in iopt_area_fill_domains()
Author: kartikey406@gmail.com


#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

KMSAN reported an uninitialized value in batch_add_pfn_num() when
accessing batch->npfns[] and batch->pfns[] arrays. This occurs because
struct pfn_reader pfns was declared without initialization, leaving
the embedded pfn_batch structure and its arrays uninitialized.

Initialize pfns to zero to ensure all fields and embedded structures
start in a known state.

Reported-by: syzbot+df28076a30d726933015@syzkaller.appspotmail.com
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
---
 drivers/iommu/iommufd/pages.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/iommufd/pages.c b/drivers/iommu/iommufd/pages.c
index dbe51ecb9a20..a07373cf013c 100644
--- a/drivers/iommu/iommufd/pages.c
+++ b/drivers/iommu/iommufd/pages.c
@@ -1897,7 +1897,7 @@ int iopt_area_fill_domains(struct iopt_area *area, struct iopt_pages *pages)
 	unsigned long done_all_end_index;
 	struct iommu_domain *domain;
 	unsigned long unmap_index;
-	struct pfn_reader pfns;
+	struct pfn_reader pfns = {};
 	unsigned long index;
 	int rc;
 
-- 
2.43.0