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2022-05-13crypto: qcom-rng - fix infinite loop on requests not multiple of WORD_SZOndrej Mosnacek1-0/+1
The commit referenced in the Fixes tag removed the 'break' from the else branch in qcom_rng_read(), causing an infinite loop whenever 'max' is not a multiple of WORD_SZ. This can be reproduced e.g. by running: kcapi-rng -b 67 >/dev/null There are many ways to fix this without adding back the 'break', but they all seem more awkward than simply adding it back, so do just that. Tested on a machine with Qualcomm Amberwing processor. Fixes: a680b1832ced ("crypto: qcom-rng - ensure buffer for generate is completely filled") Cc: stable@vger.kernel.org Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Brian Masney <bmasney@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-03-14crypto: qcom-rng - ensure buffer for generate is completely filledBrian Masney1-7/+10
The generate function in struct rng_alg expects that the destination buffer is completely filled if the function returns 0. qcom_rng_read() can run into a situation where the buffer is partially filled with randomness and the remaining part of the buffer is zeroed since qcom_rng_generate() doesn't check the return value. This issue can be reproduced by running the following from libkcapi: kcapi-rng -b 9000000 > OUTFILE The generated OUTFILE will have three huge sections that contain all zeros, and this is caused by the code where the test 'val & PRNG_STATUS_DATA_AVAIL' fails. Let's fix this issue by ensuring that qcom_rng_read() always returns with a full buffer if the function returns success. Let's also have qcom_rng_generate() return the correct value. Here's some statistics from the ent project (https://www.fourmilab.ch/random/) that shows information about the quality of the generated numbers: $ ent -c qcom-random-before Value Char Occurrences Fraction 0 606748 0.067416 1 33104 0.003678 2 33001 0.003667 ... 253 � 32883 0.003654 254 � 33035 0.003671 255 � 33239 0.003693 Total: 9000000 1.000000 Entropy = 7.811590 bits per byte. Optimum compression would reduce the size of this 9000000 byte file by 2 percent. Chi square distribution for 9000000 samples is 9329962.81, and randomly would exceed this value less than 0.01 percent of the times. Arithmetic mean value of data bytes is 119.3731 (127.5 = random). Monte Carlo value for Pi is 3.197293333 (error 1.77 percent). Serial correlation coefficient is 0.159130 (totally uncorrelated = 0.0). Without this patch, the results of the chi-square test is 0.01%, and the numbers are certainly not random according to ent's project page. The results improve with this patch: $ ent -c qcom-random-after Value Char Occurrences Fraction 0 35432 0.003937 1 35127 0.003903 2 35424 0.003936 ... 253 � 35201 0.003911 254 � 34835 0.003871 255 � 35368 0.003930 Total: 9000000 1.000000 Entropy = 7.999979 bits per byte. Optimum compression would reduce the size of this 9000000 byte file by 0 percent. Chi square distribution for 9000000 samples is 258.77, and randomly would exceed this value 42.24 percent of the times. Arithmetic mean value of data bytes is 127.5006 (127.5 = random). Monte Carlo value for Pi is 3.141277333 (error 0.01 percent). Serial correlation coefficient is 0.000468 (totally uncorrelated = 0.0). This change was tested on a Nexus 5 phone (msm8974 SoC). Signed-off-by: Brian Masney <bmasney@redhat.com> Fixes: ceec5f5b5988 ("crypto: qcom-rng - Add Qcom prng driver") Cc: stable@vger.kernel.org # 4.19+ Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Reviewed-by: Andrew Halaney <ahalaney@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-08-20crypto: algapi - Remove skbuff.h inclusionHerbert Xu1-0/+1
The header file algapi.h includes skbuff.h unnecessarily since all we need is a forward declaration for struct sk_buff. This patch removes that inclusion. Unfortunately skbuff.h pulls in a lot of things and drivers over the years have come to rely on it so this patch adds a lot of missing inclusions that result from this. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-08-09crypto: qcom-rng - use devm_platform_ioremap_resource() to simplify codeYueHaibing1-3/+1
Use devm_platform_ioremap_resource() to simplify the code a bit. This is detected by coccinelle. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-27crypto: qcom-rng - Add ACPI supportTimur Tabi1-3/+17
Add support for probing on ACPI systems, with ACPI HID QCOM8160. On ACPI systems, clocks are always enabled, the PRNG should already be enabled, and the register region is read-only. The driver only verifies that the hardware is already enabled never tries to disable or configure it. Signed-off-by: Timur Tabi <timur@codeaurora.org> Tested-by: Jeffrey Hugo <jhugo@codeaurora.org> [port to crypto API] Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-27crypto: qcom-rng - Add support for prng-eeVinod Koul1-2/+9
Qcom 8996 and later chips features multiple Execution Environments (EE) and secure world is typically responsible for configuring the prng. Add driver data for qcom,prng as 0 and qcom,prng-ee as 1 and use that to skip initialization routine. Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-27crypto: qcom-rng - Add Qcom prng driverVinod Koul1-0/+208
This ports the Qcom prng from older hw_random driver. No change of functionality and move from hw_random to crypto APIs is done. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>