From 9ae672606c17891d90b282e3490b817620549599 Mon Sep 17 00:00:00 2001 From: Cao Guanghui Date: Wed, 17 Jun 2026 14:00:52 +0800 Subject: [PATCH] dm era: fix NULL pointer dereference in metadata_open() metadata_open() returns NULL when kzalloc_obj() fails, but the caller era_ctr() only checks IS_ERR(md). Since IS_ERR(NULL) returns false, the NULL pointer is treated as a valid result and later assigned to era->md, leading to a NULL pointer dereference when the metadata is accessed. Fix this by returning ERR_PTR(-ENOMEM) on allocation failure, consistent with dm-cache-metadata.c, dm-thin-metadata.c, and dm-clone-metadata.c which all use ERR_PTR(-ENOMEM) for the same pattern. Fixes: eec40579d848 ("dm: add era target") Signed-off-by: Cao Guanghui Reviewed-by: Su Yue Reviewed-by: Ming-Hung Tsai Signed-off-by: Mikulas Patocka --- drivers/md/dm-era-target.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-era-target.c b/drivers/md/dm-era-target.c index 18aed0e2a508..cef288194804 100644 --- a/drivers/md/dm-era-target.c +++ b/drivers/md/dm-era-target.c @@ -810,8 +810,10 @@ static struct era_metadata *metadata_open(struct block_device *bdev, int r; struct era_metadata *md = kzalloc_obj(*md); - if (!md) - return NULL; + if (!md) { + DMERR("could not allocate metadata struct"); + return ERR_PTR(-ENOMEM); + } md->bdev = bdev; md->block_size = block_size;