[PATCH 1/2] nvmem: layouts: onie-tlv: fix hang on unknown types

[PATCH 1/2] nvmem: layouts: onie-tlv: fix hang on unknown types

[srini]

From: Andre Heider <a.heider@gmail.com>

The EEPROM on my board has a vendor specific entry of type 0x41. When
stumbling upon that, this driver hangs in an endless loop.

Fix it by keep incrementing the offset on unknown entries, so the loop
will eventually stop.

Fixes: d3c0d12f6474 ("nvmem: layouts: onie-tlv: Add new layout driver")
Cc: Stable@vger.kernel.org
Signed-off-by: Andre Heider <a.heider@gmail.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
---
 drivers/nvmem/layouts/onie-tlv.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/nvmem/layouts/onie-tlv.c b/drivers/nvmem/layouts/onie-tlv.c
index 0967a32319a2..8b0f3c1b8a0e 100644
--- a/drivers/nvmem/layouts/onie-tlv.c
+++ b/drivers/nvmem/layouts/onie-tlv.c
@@ -119,7 +119,7 @@ static int onie_tlv_add_cells(struct device *dev, struct nvmem_device *nvmem,
 
 		cell.name = onie_tlv_cell_name(tlv.type);
 		if (!cell.name)
-			continue;
+			goto next;
 
 		cell.offset = hdr_len + offset + sizeof(tlv.type) + sizeof(tlv.len);
 		cell.bytes = tlv.len;
@@ -132,6 +132,7 @@ static int onie_tlv_add_cells(struct device *dev, struct nvmem_device *nvmem,
 			return ret;
 		}
 
+next:
 		offset += sizeof(tlv) + tlv.len;
 	}
 
-- 
2.53.0

[PATCH 2/2] nvmem: core: fix use-after-free bugs in error paths

[srini]

From: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Fix several instances of error paths in which we call
__nvmem_device_put() - which may end up freeing the underlying memory
and other resources - and then keep on using the nvmem structure. Always
put the reference to the nvmem device as the last step before returning
the error code.

Cc: stable@vger.kernel.org
Fixes: 7ae6478b304b ("nvmem: core: rework nvmem cell instance creation")
Fixes: e888d445ac33 ("nvmem: resolve cells from DT at registration time")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
---
 drivers/nvmem/core.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 311cb2e5a5c0..e871181751f3 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -1468,18 +1468,16 @@ struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id)
 	cell_entry = nvmem_find_cell_entry_by_node(nvmem, cell_np);
 	of_node_put(cell_np);
 	if (!cell_entry) {
-		__nvmem_device_put(nvmem);
 		nvmem_layout_module_put(nvmem);
-		if (nvmem->layout)
-			return ERR_PTR(-EPROBE_DEFER);
-		else
-			return ERR_PTR(-ENOENT);
+		ret = nvmem->layout ? -EPROBE_DEFER : -ENOENT;
+		__nvmem_device_put(nvmem);
+		return ERR_PTR(ret);
 	}
 
 	cell = nvmem_create_cell(cell_entry, id, cell_index);
 	if (IS_ERR(cell)) {
-		__nvmem_device_put(nvmem);
 		nvmem_layout_module_put(nvmem);
+		__nvmem_device_put(nvmem);
 	}
 
 	return cell;
@@ -1593,8 +1591,8 @@ void nvmem_cell_put(struct nvmem_cell *cell)
 		kfree_const(cell->id);
 
 	kfree(cell);
-	__nvmem_device_put(nvmem);
 	nvmem_layout_module_put(nvmem);
+	__nvmem_device_put(nvmem);
 }
 EXPORT_SYMBOL_GPL(nvmem_cell_put);
 
-- 
2.53.0