+ resource-fix-resource-leak-in-get_free_mem_region.patch added to mm-nonmm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: resource: fix resource leak in get_free_mem_region()
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     resource-fix-resource-leak-in-get_free_mem_region.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/resource-fix-resource-leak-in-get_free_mem_region.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Li Zhijian <lizhijian@fujitsu.com>
Subject: resource: fix resource leak in get_free_mem_region()
Date: Tue, 4 Mar 2025 12:34:15 +0800

The leak is detected by the kernel memory leak detector (`kmemleak`)
following a `cxl create-region` failure:

 cxl_acpi ACPI0017:00: decoder0.0: created region2
 cxl region2: HPA allocation error (-34) for size:0x0000000100000000 in CXL Window 0 [mem 0xa90000000-0x1a8fffffff flags 0x200]
 kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak)

    __kmalloc_cache_noprof+0x28c/0x350
    get_free_mem_region+0x45/0x380
    alloc_free_mem_region+0x1d/0x30
    size_store+0x180/0x290 [cxl_core]
    kernfs_fop_write_iter+0x13f/0x1e0
    vfs_write+0x37c/0x540
    ksys_write+0x68/0xe0
    do_syscall_64+0x6e/0x190
    entry_SYSCALL_64_after_hwframe+0x76/0x7e

Link: https://lkml.kernel.org/r/20250304043415.610286-1-lizhijian@fujitsu.com
Fixes: 14b80582c43e ("resource: Introduce alloc_free_mem_region()")
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Cc: Andriy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Dan Wiliams <dan.j.williams@intel.com>
Cc: "Huang, Ying" <huang.ying.caritas@gmail.com>
Cc: Ilpo Jarvinen <ilpo.jarvinen@linux.intel.com>
Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com>
Cc: Mika Westeberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/resource.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/kernel/resource.c~resource-fix-resource-leak-in-get_free_mem_region
+++ a/kernel/resource.c
@@ -2000,6 +2000,8 @@ get_free_mem_region(struct device *dev,
 		devres_free(dr);
 	} else if (dev)
 		devm_release_action(dev, remove_free_mem_region, res);
+	else
+		free_resource(res);
 
 	return ERR_PTR(-ERANGE);
 }
_

Patches currently in -mm which might be from lizhijian@fujitsu.com are

resource-fix-resource-leak-in-get_free_mem_region.patch