On Wed, Jun 17, 2026 at 2:12 PM <[email protected]> wrote: > > From: Cao Guanghui <[email protected]> > > 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 <[email protected]>
Thanks for the patch! Reviewed-by: Ming-Hung Tsai <[email protected]> > --- > 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 05285c04ff2c..08ce96e8cf4f 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; > -- > 2.25.1 > >
