From a1abf71827834345219adc8e2a361ef2faa0d1bc Mon Sep 17 00:00:00 2001 From: =?utf8?q?Rafa=C5=82=20Mi=C5=82ecki?= Date: Thu, 5 Jan 2023 13:33:18 +0100 Subject: [PATCH] kernel: fix bugs added with mac-address-ascii support MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 1. Check for -EPROBE_DEFER If it occurs we have to return immediately. Trying other properties could result in another error and ignoring -EPROBE_DEFER which has a special meaning. 2. Check for read result Assuming property->read() success can result in NULL pointer dereference. It happens e.g. for "mac-address" with NVMEM cell containing invalid MAC. 3. Simplify code Don't move cell reading & nvmem_cell_put() into a loop. Simplify loop code. Fixes: ecd81de7a5ab ("ath79: add nvmem cell mac-address-ascii support") Cc: Yousong Zhou Signed-off-by: Rafał Miłecki --- ...of_net-add-mac-address-ascii-support.patch | 39 +++++++++---------- ...of_net-add-mac-address-ascii-support.patch | 39 +++++++++---------- 2 files changed, 38 insertions(+), 40 deletions(-) diff --git a/target/linux/generic/hack-5.10/601-of_net-add-mac-address-ascii-support.patch b/target/linux/generic/hack-5.10/601-of_net-add-mac-address-ascii-support.patch index 5dd70f5f718..cf2a26c9d6a 100644 --- a/target/linux/generic/hack-5.10/601-of_net-add-mac-address-ascii-support.patch +++ b/target/linux/generic/hack-5.10/601-of_net-add-mac-address-ascii-support.patch @@ -75,36 +75,35 @@ Submitted-by: Yousong Zhou /** * Obtain the MAC address from an nvmem cell named 'mac-address' associated * with given device. -@@ -552,19 +609,23 @@ int nvmem_get_mac_address(struct device +@@ -550,21 +607,28 @@ EXPORT_SYMBOL(eth_platform_get_mac_addre + */ + int nvmem_get_mac_address(struct device *dev, void *addrbuf) { ++ struct nvmem_cell_mac_address_property *property; struct nvmem_cell *cell; const void *mac; - size_t len; -+ struct nvmem_cell_mac_address_property *property; + int i; - -- cell = nvmem_cell_get(dev, "mac-address"); -- if (IS_ERR(cell)) -- return PTR_ERR(cell); -- -- mac = nvmem_cell_read(cell, &len); -- nvmem_cell_put(cell); -- -- if (IS_ERR(mac)) -- return PTR_ERR(mac); ++ + for (i = 0; i < ARRAY_SIZE(nvmem_cell_mac_address_properties); i++) { + property = &nvmem_cell_mac_address_properties[i]; + cell = nvmem_cell_get(dev, property->name); -+ if (IS_ERR(cell)) { -+ if (i == ARRAY_SIZE(nvmem_cell_mac_address_properties) - 1) -+ return PTR_ERR(cell); -+ continue; -+ } -+ mac = property->read(cell); -+ nvmem_cell_put(cell); -+ break; ++ /* For -EPROBE_DEFER don't try other properties. We'll get back to this one. */ ++ if (!IS_ERR(cell) || PTR_ERR(cell) == -EPROBE_DEFER) ++ break; + } +- cell = nvmem_cell_get(dev, "mac-address"); + if (IS_ERR(cell)) + return PTR_ERR(cell); + +- mac = nvmem_cell_read(cell, &len); ++ mac = property->read(cell); + nvmem_cell_put(cell); +- + if (IS_ERR(mac)) + return PTR_ERR(mac); + - if (len != ETH_ALEN || !is_valid_ether_addr(mac)) { + if (!is_valid_ether_addr(mac)) { kfree(mac); diff --git a/target/linux/generic/hack-5.15/601-of_net-add-mac-address-ascii-support.patch b/target/linux/generic/hack-5.15/601-of_net-add-mac-address-ascii-support.patch index 4ab05b4ea6f..eb390961d78 100644 --- a/target/linux/generic/hack-5.15/601-of_net-add-mac-address-ascii-support.patch +++ b/target/linux/generic/hack-5.15/601-of_net-add-mac-address-ascii-support.patch @@ -75,36 +75,35 @@ Submitted-by: Yousong Zhou /** * nvmem_get_mac_address - Obtain the MAC address from an nvmem cell named * 'mac-address' associated with given device. -@@ -551,19 +608,23 @@ int nvmem_get_mac_address(struct device +@@ -549,21 +606,28 @@ EXPORT_SYMBOL(eth_platform_get_mac_addre + */ + int nvmem_get_mac_address(struct device *dev, void *addrbuf) { ++ struct nvmem_cell_mac_address_property *property; struct nvmem_cell *cell; const void *mac; - size_t len; -+ struct nvmem_cell_mac_address_property *property; + int i; - -- cell = nvmem_cell_get(dev, "mac-address"); -- if (IS_ERR(cell)) -- return PTR_ERR(cell); -- -- mac = nvmem_cell_read(cell, &len); -- nvmem_cell_put(cell); -- -- if (IS_ERR(mac)) -- return PTR_ERR(mac); ++ + for (i = 0; i < ARRAY_SIZE(nvmem_cell_mac_address_properties); i++) { + property = &nvmem_cell_mac_address_properties[i]; + cell = nvmem_cell_get(dev, property->name); -+ if (IS_ERR(cell)) { -+ if (i == ARRAY_SIZE(nvmem_cell_mac_address_properties) - 1) -+ return PTR_ERR(cell); -+ continue; -+ } -+ mac = property->read(cell); -+ nvmem_cell_put(cell); -+ break; ++ /* For -EPROBE_DEFER don't try other properties. We'll get back to this one. */ ++ if (!IS_ERR(cell) || PTR_ERR(cell) == -EPROBE_DEFER) ++ break; + } +- cell = nvmem_cell_get(dev, "mac-address"); + if (IS_ERR(cell)) + return PTR_ERR(cell); + +- mac = nvmem_cell_read(cell, &len); ++ mac = property->read(cell); + nvmem_cell_put(cell); +- + if (IS_ERR(mac)) + return PTR_ERR(mac); + - if (len != ETH_ALEN || !is_valid_ether_addr(mac)) { + if (!is_valid_ether_addr(mac)) { kfree(mac); -- 2.30.2