In the Linux kernel, the following vulnerability has been resolved: crypto: atmel-sha204a - fix blocking and non-blocking rng logic The blocking and non-blocking paths were failing to provide valid entropy due to improper buffer management. Reading the buffer starting from byte 1, only fetch the 32 bytes of random data from the return message. Tested on an Atmel SHA204A device. Before (here for blocking), tests showed repeatedly reading reduced bytes. $ head -c 32 /dev/hwrng | hexdump -C 00000000 02 28 85 b3 47 40 f2 ee 00 00 00 00 00 00 00 00 |.(..G@..........| 00000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 00000020 After, the result will be similar to the following: $ head -c 32 /dev/hwrng | hexdump -C 00000000 5a fc 3f 13 14 68 fe 06 68 0a bd 04 83 6e 09 69 |Z.?..h..h....n.i| 00000010 75 ff cf 87 10 84 3b c9 c1 df ae eb 45 53 4c c3 |u.....;.....ESL.| 00000020
https://git.kernel.org/stable/c/e833e865e4944ba75120db534bd931db6cf677d3
https://git.kernel.org/stable/c/d4aa6141ff03ec82eed6fcef814300fb855ce5d8
https://git.kernel.org/stable/c/aac63bbea8fd5a34f1a4305cb73369068f952d32
https://git.kernel.org/stable/c/938ae1fb4a8f5db43b62b6206d409efbf317f0d9
https://git.kernel.org/stable/c/9039bb4f238474379221fc933c34f19f0cba501b
https://git.kernel.org/stable/c/76269a91fd9560c5f03c3e59421a0329e39a6661
https://git.kernel.org/stable/c/319400fc5ee15db5793aa45f854968141326effc
https://git.kernel.org/stable/c/2fa302bbc62dec7cb6339c9494e0e3f2f884afeb