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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:25:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:25:51 +0000 |
commit | ac8399db6ce846597966360732ce6d39a247bdd2 (patch) | |
tree | 046a28d2cbd02afa147291e8f69e9bb5dc29f1aa /debian/patches/random-util-eat-up-bad-RDRAND-values-seen-on-AMD-CPUs.patch | |
parent | Adding upstream version 241. (diff) | |
download | systemd-ac8399db6ce846597966360732ce6d39a247bdd2.tar.xz systemd-ac8399db6ce846597966360732ce6d39a247bdd2.zip |
Adding debian version 241-7~deb10u8.debian/241-7_deb10u8
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'debian/patches/random-util-eat-up-bad-RDRAND-values-seen-on-AMD-CPUs.patch')
-rw-r--r-- | debian/patches/random-util-eat-up-bad-RDRAND-values-seen-on-AMD-CPUs.patch | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/debian/patches/random-util-eat-up-bad-RDRAND-values-seen-on-AMD-CPUs.patch b/debian/patches/random-util-eat-up-bad-RDRAND-values-seen-on-AMD-CPUs.patch new file mode 100644 index 0000000..5c464ad --- /dev/null +++ b/debian/patches/random-util-eat-up-bad-RDRAND-values-seen-on-AMD-CPUs.patch @@ -0,0 +1,54 @@ +From: Michael Biebl <biebl@debian.org> +Date: Tue, 14 May 2019 13:12:35 +0200 +Subject: random-util: eat up bad RDRAND values seen on AMD CPUs + +An ugly, ugly work-around for #11810. And no, we shouldn't have to do +this. This is something for AMD, the firmware or the kernel to +fix/work-around, not us. But nonetheless, this should do it for now. + +Fixes: #11810 +(cherry picked from commit 1c53d4a070edbec8ad2d384ba0014d0eb6bae077) +--- + src/basic/random-util.c | 15 ++++++++++++++- + 1 file changed, 14 insertions(+), 1 deletion(-) + +diff --git a/src/basic/random-util.c b/src/basic/random-util.c +index f7decf6..38f8180 100644 +--- a/src/basic/random-util.c ++++ b/src/basic/random-util.c +@@ -37,6 +37,7 @@ int rdrand(unsigned long *ret) { + + #if defined(__i386__) || defined(__x86_64__) + static int have_rdrand = -1; ++ unsigned long v; + unsigned char err; + + if (have_rdrand < 0) { +@@ -56,7 +57,7 @@ int rdrand(unsigned long *ret) { + + asm volatile("rdrand %0;" + "setc %1" +- : "=r" (*ret), ++ : "=r" (v), + "=qm" (err)); + + #if HAS_FEATURE_MEMORY_SANITIZER +@@ -66,6 +67,18 @@ int rdrand(unsigned long *ret) { + if (!err) + return -EAGAIN; + ++ /* Apparently on some AMD CPUs RDRAND will sometimes (after a suspend/resume cycle?) report success ++ * via the carry flag but nonetheless return the same fixed value -1 in all cases. This appears to be ++ * a bad bug in the CPU or firmware. Let's deal with that and work-around this by explicitly checking ++ * for this special value (and also 0, just to be sure) and filtering it out. This is a work-around ++ * only however and something AMD really should fix properly. The Linux kernel should probably work ++ * around this issue by turning off RDRAND altogether on those CPUs. See: ++ * https://github.com/systemd/systemd/issues/11810 */ ++ if (v == 0 || v == ULONG_MAX) ++ return log_debug_errno(SYNTHETIC_ERRNO(EUCLEAN), ++ "RDRAND returned suspicious value %lx, assuming bad hardware RNG, not using value.", v); ++ ++ *ret = v; + return 0; + #else + return -EOPNOTSUPP; |