devm_*() family of functions purpose is managing memory attached to a
device. So in general it should only be used for allocations that should
last for the whole lifecycle of the device. This is not the case for
acpi_nfit_init_interleave_set(). There are two allocations that are only
used locally in this function.

Fix this by switching from devm_kcalloc() to kcalloc(), and adding
modern scope based rollback. This is similar to C++ RAII and is
preferred way for handling local memory allocations.

Reported-by: Andy Shevchenko <andy.shevche...@gmail.com>
Suggested-by: Dave Jiang <dave.ji...@intel.com>
Suggested-by: Andy Shevchenko <andy.shevche...@gmail.com>
Reviewed-by: Dave Jiang <dave.ji...@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevche...@gmail.com>
Signed-off-by: Michal Wilczynski <michal.wilczyn...@intel.com>
---
v2:
 - removed first commit from the patchset, as the commit couldn't
   be marked as a fix
 - squashed those commits together, since the second one were
   mostly overwriting the previous one

 drivers/acpi/nfit/core.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 3826f49d481b..67a844a705c4 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -2257,26 +2257,23 @@ static int acpi_nfit_init_interleave_set(struct 
acpi_nfit_desc *acpi_desc,
                struct nd_region_desc *ndr_desc,
                struct acpi_nfit_system_address *spa)
 {
+       u16 nr = ndr_desc->num_mappings;
+       struct nfit_set_info2 *info2 __free(kfree) =
+               kcalloc(nr, sizeof(*info2), GFP_KERNEL);
+       struct nfit_set_info *info __free(kfree) =
+               kcalloc(nr, sizeof(*info), GFP_KERNEL);
        struct device *dev = acpi_desc->dev;
        struct nd_interleave_set *nd_set;
-       u16 nr = ndr_desc->num_mappings;
-       struct nfit_set_info2 *info2;
-       struct nfit_set_info *info;
        int i;
 
+       if (!info || !info2)
+               return -ENOMEM;
+
        nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
        if (!nd_set)
                return -ENOMEM;
        import_guid(&nd_set->type_guid, spa->range_guid);
 
-       info = devm_kcalloc(dev, nr, sizeof(*info), GFP_KERNEL);
-       if (!info)
-               return -ENOMEM;
-
-       info2 = devm_kcalloc(dev, nr, sizeof(*info2), GFP_KERNEL);
-       if (!info2)
-               return -ENOMEM;
-
        for (i = 0; i < nr; i++) {
                struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
                struct nvdimm *nvdimm = mapping->nvdimm;
@@ -2337,8 +2334,6 @@ static int acpi_nfit_init_interleave_set(struct 
acpi_nfit_desc *acpi_desc,
        }
 
        ndr_desc->nd_set = nd_set;
-       devm_kfree(dev, info);
-       devm_kfree(dev, info2);
 
        return 0;
 }
-- 
2.41.0


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