On Thu, 26 Jul 2018 09:52:11 -0700 Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > See the section "Kernel addresses" in > Documentation/security/self-protection. IIRC, the issue is that a > process may have CAP_SYSLOG but not necessarily CAP_SYS_ADMIN (so it > can read dmesg, but not necessarily issue a sysctl to change > kptr_restrict), get compromised and used to leak kernel addresses, > which can then be used to defeat KASLR. But the code doesn't go to dmesg. It's only available via /sys/kernel/debug/tracing/printk_formats which is only available via root. Nobody else has access to that directory. -- Steve
