kernel/linux.git/drivers/of/device.c, branch v6.1.168

of: module: add buffer overflow check in of_modalias()

2025-05-02T05:47:08+00:00

commit cf7385cb26ac4f0ee6c7385960525ad534323252 upstream. In of_modalias(), if the buffer happens to be too small even for the 1st snprintf() call, the len parameter will become negative and str parameter (if not NULL initially) will point beyond the buffer's end. Add the buffer overflow check after the 1st snprintf() call and fix such check after the strlen() call (accounting for the terminating NUL char). Fixes: bc575064d688 ("of/device: use of_property_for_each_string to parse compatible strings") Signed-off-by: Sergey Shtylyov Link: https://lore.kernel.org/r/bbfc6be0-c687-62b6-d015-5141b93f313e@omp.ru Signed-off-by: Rob Herring Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman

of: Fix modalias string generation

2023-05-11T14:03:28+00:00

[ Upstream commit b19a4266c52de78496fe40f0b37580a3b762e67d ] The helper generating an OF based modalias (of_device_get_modalias()) works fine, but due to the use of snprintf() internally it needs a buffer one byte longer than what should be needed just for the entire string (excluding the '\0'). Most users of this helper are sysfs hooks providing the modalias string to users. They all provide a PAGE_SIZE buffer which is way above the number of bytes required to fit the modalias string and hence do not suffer from this issue. There is another user though, of_device_request_module(), which is only called by drivers/usb/common/ulpi.c. This request module function is faulty, but maybe because in most cases there is an alternative, ULPI driver users have not noticed it. In this function, of_device_get_modalias() is called twice. The first time without buffer just to get the number of bytes required by the modalias string (excluding the null byte), and a second time, after buffer allocation, to fill the buffer. The allocation asks for an additional byte, in order to store the trailing '\0'. However, the buffer *length* provided to of_device_get_modalias() excludes this extra byte. The internal use of snprintf() with a length that is exactly the number of bytes to be written has the effect of using the last available byte to store a '\0', which then smashes the last character of the modalias string. Provide the actual size of the buffer to of_device_get_modalias() to fix this issue. Note: the "str[size - 1] = '\0';" line is not really needed as snprintf will anyway end the string with a null byte, but there is a possibility that this function might be called on a struct device_node without compatible, in this case snprintf() would not be executed. So we keep it just to avoid possible unbounded strings. Cc: Stephen Boyd Cc: Peter Chen Fixes: 9c829c097f2f ("of: device: Support loading a module with OF based modalias") Signed-off-by: Miquel Raynal Reviewed-by: Rob Herring Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20230404172148.82422-2-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

of: Fix "dma-ranges" handling for bus controllers

2022-09-30T19:35:43+00:00

Commit 951d48855d86 ("of: Make of_dma_get_range() work on bus nodes") relaxed the handling of "dma-ranges" for any leaf node on the assumption that it would still represent a usage error for the property to be present on a non-bus leaf node. However there turns out to be a fiddly case where a bus also represents a DMA-capable device in its own right, such as a PCIe root complex with an integrated DMA engine on its platform side. In such cases, "dma-ranges" translation is entirely valid for devices discovered behind the bus, but should not be erroneously applied to the bus controller device itself which operates in its parent's address space. Fix this by restoring the previous behaviour for the specific case where a device is configured via its own OF node, since it is logical to assume that a device should never represent its own parent bus. Reported-by: Serge Semin Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/112e8f3d3e7c054ecf5e12b5ac0aa5596ec00681.1664455433.git.robin.murphy@arm.com Signed-off-by: Rob Herring

of: device: Fix missing of_node_put() in of_dma_set_restricted_buffer

2022-07-12T16:58:33+00:00

We should use of_node_put() for the reference 'node' returned by of_parse_phandle() which will increase the refcount. Fixes: fec9b625095f ("of: Add plumbing for restricted DMA pool") Co-authored-by: Miaoqian Lin Signed-off-by: Liang He Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20220702014449.263772-1-windhl@126.com

of: Check 'of_node_reused' flag on of_match_device()

2022-01-20T18:55:26+00:00

Commit 0f153a1b8193 ("usb: chipidea: Set the DT node on the child device") caused the child device to match on the parent driver instead of the child's driver since the child's DT node pointer matched. The worst case result is a loop of the parent driver probing another instance and creating yet another child device eventually exhausting the stack. If the child driver happens to match first, then everything works fine. A device sharing the DT node should never do DT based driver matching, so let's simply check of_node_reused in of_match_device() to prevent that. Fixes: 0f153a1b8193 ("usb: chipidea: Set the DT node on the child device") Link: https://lore.kernel.org/all/20220114105620.GK18506@ediswmail.ad.cirrus.com/ Reported-by: Charles Keepax Cc: Frank Rowand Cc: Arnd Bergmann Cc: Tony Lindgren Cc: Greg Kroah-Hartman Cc: Peter Chen Tested-by: Charles Keepax Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20220118173404.1891800-1-robh@kernel.org

of: restricted dma: Fix condition for rmem init

2021-09-17T20:58:09+00:00

of_dma_set_restricted_buffer fails to handle negative return values from of_property_count_elems_of_size, e.g. when the property does not exist. This results in an attempt to assign a non-existent reserved memory region to the device and a warning being printed. Fix the condition to take negative values into account. Fixes: f3cfd136aef0 ("of: restricted dma: Don't fail device probe on rmem init failure") Cc: Will Deacon Signed-off-by: David Brazdil Acked-by: Will Deacon Link: https://lore.kernel.org/r/20210917131423.2760155-1-dbrazdil@google.com Signed-off-by: Rob Herring

of: restricted dma: Don't fail device probe on rmem init failure

2021-08-23T10:32:04+00:00

If CONFIG_DMA_RESTRICTED_POOL=n then probing a device with a reference to a "restricted-dma-pool" will fail with a reasonably cryptic error: | pci-host-generic: probe of 10000.pci failed with error -22 Rework of_dma_set_restricted_buffer() so that it does not cause probing failure and instead either returns early if CONFIG_DMA_RESTRICTED_POOL=n or emits a diagnostic if the reserved DMA pool fails to initialise. Cc: Claire Chang Cc: Konrad Rzeszutek Wilk Cc: Christoph Hellwig Cc: Rob Herring Cc: Robin Murphy Signed-off-by: Will Deacon Signed-off-by: Konrad Rzeszutek Wilk

of: Move of_dma_set_restricted_buffer() into device.c

2021-08-23T10:32:02+00:00

Rob observes that: | of_dma_set_restricted_buffer() [...] should also be moved to | of/device.c. There's no reason for it to be in of/address.c. It has | nothing to do with address parsing. Move it to of/device.c, as he suggests. Cc: Claire Chang Cc: Konrad Rzeszutek Wilk Cc: Christoph Hellwig Cc: Robin Murphy Suggested-by: Rob Herring Link: https://lore.kernel.org/r/CAL_JsqJ7ROWWJX84x2kEex9NQ8G+2=ybRuNOobX+j8bjZzSemQ@mail.gmail.com Signed-off-by: Will Deacon Signed-off-by: Konrad Rzeszutek Wilk

of: Add plumbing for restricted DMA pool

2021-07-14T00:04:53+00:00

If a device is not behind an IOMMU, we look up the device node and set up the restricted DMA when the restricted-dma-pool is presented. Signed-off-by: Claire Chang Tested-by: Stefano Stabellini Tested-by: Will Deacon Signed-off-by: Konrad Rzeszutek Wilk

of: device: Fix function name in header and provide missing descriptions

2021-03-23T21:27:52+00:00

Fixes the following W=1 kernel build warning(s): drivers/of/device.c:72: warning: expecting prototype for of_dma_configure(). Prototype was for of_dma_configure_id() instead drivers/of/device.c:263: warning: Function parameter or member 'dev' not described in 'of_device_modalias' drivers/of/device.c:263: warning: Function parameter or member 'str' not described in 'of_device_modalias' drivers/of/device.c:263: warning: Function parameter or member 'len' not described in 'of_device_modalias' drivers/of/device.c:280: warning: Function parameter or member 'dev' not described in 'of_device_uevent' drivers/of/device.c:280: warning: Function parameter or member 'env' not described in 'of_device_uevent' Cc: Rob Herring Cc: Frank Rowand Cc: devicetree@vger.kernel.org Signed-off-by: Lee Jones Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20210318104036.3175910-2-lee.jones@linaro.org