6.5-stable review patch. If anyone has any objections, please let me know.
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From: Junhao He hejunhao3@huawei.com
[ Upstream commit 1a9e02673e2550f5612099e64e8761f0c8fc0f50 ]
There are memory leaks reported by kmemleak: ... unreferenced object 0xffff00213c141000 (size 1024): comm "systemd-udevd", pid 2123, jiffies 4294909467 (age 6062.160s) hex dump (first 32 bytes): 04 00 00 00 02 00 00 00 18 10 14 3c 21 00 ff ff ...........<!... 00 00 00 00 00 00 00 00 03 00 00 00 10 00 00 00 ................ backtrace: [<000000004b7c9001>] __kmem_cache_alloc_node+0x2f8/0x348 [<00000000b0fc7ceb>] __kmalloc+0x58/0x108 [<0000000064ff4695>] acpi_os_allocate+0x2c/0x68 [<000000007d57d116>] acpi_ut_initialize_buffer+0x54/0xe0 [<0000000024583908>] acpi_evaluate_object+0x388/0x438 [<0000000017b2e72b>] acpi_evaluate_object_typed+0xe8/0x240 [<000000005df0eac2>] coresight_get_platform_data+0x1b4/0x988 [coresight] ...
The ACPI buffer memory (buf.pointer) should be freed. But the buffer is also used after returning from acpi_get_dsd_graph(). Move the temporary variables buf to acpi_coresight_parse_graph(), and free it before the function return to prevent memory leak.
Fixes: 76ffa5ab5b79 ("coresight: Support for ACPI bindings") Signed-off-by: Junhao He hejunhao3@huawei.com Reviewed-by: James Clark james.clark@arm.com Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Link: https://lore.kernel.org/r/20230817085937.55590-2-hejunhao3@huawei.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../hwtracing/coresight/coresight-platform.c | 40 ++++++++++++------- 1 file changed, 26 insertions(+), 14 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c index c8940314cceb8..dbf508fdd8d16 100644 --- a/drivers/hwtracing/coresight/coresight-platform.c +++ b/drivers/hwtracing/coresight/coresight-platform.c @@ -494,19 +494,18 @@ static inline bool acpi_validate_dsd_graph(const union acpi_object *graph)
/* acpi_get_dsd_graph - Find the _DSD Graph property for the given device. */ static const union acpi_object * -acpi_get_dsd_graph(struct acpi_device *adev) +acpi_get_dsd_graph(struct acpi_device *adev, struct acpi_buffer *buf) { int i; - struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; acpi_status status; const union acpi_object *dsd;
status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, - &buf, ACPI_TYPE_PACKAGE); + buf, ACPI_TYPE_PACKAGE); if (ACPI_FAILURE(status)) return NULL;
- dsd = buf.pointer; + dsd = buf->pointer;
/* * _DSD property consists tuples { Prop_UUID, Package() } @@ -557,12 +556,12 @@ acpi_validate_coresight_graph(const union acpi_object *cs_graph) * returns NULL. */ static const union acpi_object * -acpi_get_coresight_graph(struct acpi_device *adev) +acpi_get_coresight_graph(struct acpi_device *adev, struct acpi_buffer *buf) { const union acpi_object *graph_list, *graph; int i, nr_graphs;
- graph_list = acpi_get_dsd_graph(adev); + graph_list = acpi_get_dsd_graph(adev, buf); if (!graph_list) return graph_list;
@@ -663,22 +662,24 @@ static int acpi_coresight_parse_graph(struct device *dev, struct acpi_device *adev, struct coresight_platform_data *pdata) { + int ret = 0; int i, nlinks; const union acpi_object *graph; struct coresight_connection conn, zero_conn = {}; struct coresight_connection *new_conn; + struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
- graph = acpi_get_coresight_graph(adev); + graph = acpi_get_coresight_graph(adev, &buf); /* * There are no graph connections, which is fine for some components. * e.g., ETE */ if (!graph) - return 0; + goto free;
nlinks = graph->package.elements[2].integer.value; if (!nlinks) - return 0; + goto free;
for (i = 0; i < nlinks; i++) { const union acpi_object *link = &graph->package.elements[3 + i]; @@ -686,17 +687,28 @@ static int acpi_coresight_parse_graph(struct device *dev,
conn = zero_conn; dir = acpi_coresight_parse_link(adev, link, &conn); - if (dir < 0) - return dir; + if (dir < 0) { + ret = dir; + goto free; + }
if (dir == ACPI_CORESIGHT_LINK_MASTER) { new_conn = coresight_add_out_conn(dev, pdata, &conn); - if (IS_ERR(new_conn)) - return PTR_ERR(new_conn); + if (IS_ERR(new_conn)) { + ret = PTR_ERR(new_conn); + goto free; + } } }
- return 0; +free: + /* + * When ACPI fails to alloc a buffer, it will free the buffer + * created via ACPI_ALLOCATE_BUFFER and set to NULL. + * ACPI_FREE can handle NULL pointers, so free it directly. + */ + ACPI_FREE(buf.pointer); + return ret; }
/*