Update the README

diff --git a/README.md b/README.md
index 846988528435c45fc09cc3f36717744d15bc9215..db578e87314c2ed5ab9a19b511d345a9a33edf0f 100644 (file)
--- a/README.md
+++ b/README.md
@@ -12,14 +12,14 @@ make our systems more secure.
 
 But nobody likes checking configs manually. So let the computers do their job!
 
 
 But nobody likes checking configs manually. So let the computers do their job!
 

-__kconfig-hardened-check.py__ helps me to check the Linux kernel options
+__kconfig-hardened-check__ helps me to check the Linux kernel options

 against my security hardening preferences, which are based on the
 
   - [KSPP recommended settings][1],
   - [CLIP OS kernel configuration][2],
   - Last public [grsecurity][3] patch (options which they disable),
   - [SECURITY_LOCKDOWN_LSM][5] patchset,
 against my security hardening preferences, which are based on the
 
   - [KSPP recommended settings][1],
   - [CLIP OS kernel configuration][2],
   - Last public [grsecurity][3] patch (options which they disable),
   - [SECURITY_LOCKDOWN_LSM][5] patchset,

-  - Direct feedback from Linux kernel maintainers (see [#38][6], [#53][15], [#54][16], [#62][17]).
+  - [Direct feedback from the Linux kernel maintainers][23].

 
 This tool supports checking __Kconfig__ options and __kernel cmdline__ parameters.
 
 
 This tool supports checking __Kconfig__ options and __kernel cmdline__ parameters.
 


@@ -34,7 +34,7 @@ or exploitation techniques.
   - ARM64
   - ARM
 
   - ARM64
   - ARM
 

-TODO: RISC-V
+TODO: RISC-V (the issue [#56][22])

 
 ## Installation
 
 
 ## Installation
 


@@ -87,7 +87,7 @@ CONFIG_DEVMEM                                | is not set  |   kspp   | cut_atta
   - `-m show_ok` for showing only the successful checks
   - `-m json` for printing the results in JSON format (for combining `kconfig-hardened-check` with other tools)
 
   - `-m show_ok` for showing only the successful checks
   - `-m json` for printing the results in JSON format (for combining `kconfig-hardened-check` with other tools)
 

-## Example output for `Fedora 34` kernel config
+## Example output for `Fedora 34` kernel configuration

 ```
 $ ./bin/kconfig-hardened-check -c /boot/config-5.19.4-200.fc36.x86_64 -l /proc/cmdline
 [+] Kconfig file to check: /boot/config-5.19.4-200.fc36.x86_64
 ```
 $ ./bin/kconfig-hardened-check -c /boot/config-5.19.4-200.fc36.x86_64 -l /proc/cmdline
 [+] Kconfig file to check: /boot/config-5.19.4-200.fc36.x86_64


@@ -166,6 +166,7 @@ CONFIG_STACKLEAK_RUNTIME_DISABLE        |kconfig| is not set |  clipos  | self_p
 CONFIG_INTEL_IOMMU_DEFAULT_ON           |kconfig|     y      |  clipos  | self_protection  | FAIL: "is not set"
 CONFIG_INTEL_IOMMU_SVM                  |kconfig|     y      |  clipos  | self_protection  | OK
 CONFIG_RESET_ATTACK_MITIGATION          |kconfig|     y      |    my    | self_protection  | FAIL: "is not set"
 CONFIG_INTEL_IOMMU_DEFAULT_ON           |kconfig|     y      |  clipos  | self_protection  | FAIL: "is not set"
 CONFIG_INTEL_IOMMU_SVM                  |kconfig|     y      |  clipos  | self_protection  | OK
 CONFIG_RESET_ATTACK_MITIGATION          |kconfig|     y      |    my    | self_protection  | FAIL: "is not set"

+CONFIG_UBSAN_LOCAL_BOUNDS               |kconfig|     y      |    my    | self_protection  | FAIL: not found

 CONFIG_SLS                              |kconfig|     y      |    my    | self_protection  | OK
 CONFIG_AMD_IOMMU_V2                     |kconfig|     y      |    my    | self_protection  | FAIL: "m"
 CONFIG_SECURITY                         |kconfig|     y      |defconfig | security_policy  | OK
 CONFIG_SLS                              |kconfig|     y      |    my    | self_protection  | OK
 CONFIG_AMD_IOMMU_V2                     |kconfig|     y      |    my    | self_protection  | FAIL: "m"
 CONFIG_SECURITY                         |kconfig|     y      |defconfig | security_policy  | OK


@@ -275,29 +276,33 @@ CONFIG_INPUT_EVBUG                      |kconfig| is not set |    my    |cut_att
 CONFIG_KGDB                             |kconfig| is not set |    my    |cut_attack_surface| FAIL: "y"
 CONFIG_INTEGRITY                        |kconfig|     y      |defconfig | harden_userspace | OK
 CONFIG_ARCH_MMAP_RND_BITS               |kconfig|     32     |  clipos  | harden_userspace | FAIL: "28"
 CONFIG_KGDB                             |kconfig| is not set |    my    |cut_attack_surface| FAIL: "y"
 CONFIG_INTEGRITY                        |kconfig|     y      |defconfig | harden_userspace | OK
 CONFIG_ARCH_MMAP_RND_BITS               |kconfig|     32     |  clipos  | harden_userspace | FAIL: "28"

+nosmep                                  |cmdline| is not set |defconfig | self_protection  | OK: not found
+nosmap                                  |cmdline| is not set |defconfig | self_protection  | OK: not found
+nokaslr                                 |cmdline| is not set |defconfig | self_protection  | OK: not found
+nopti                                   |cmdline| is not set |defconfig | self_protection  | OK: not found
+nospectre_v1                            |cmdline| is not set |defconfig | self_protection  | OK: not found
+nospectre_v2                            |cmdline| is not set |defconfig | self_protection  | OK: not found

 rodata                                  |cmdline|     1      |defconfig | self_protection  | OK: rodata not found
 init_on_alloc                           |cmdline|     1      |   kspp   | self_protection  | FAIL: not found
 init_on_free                            |cmdline|     1      |   kspp   | self_protection  | FAIL: not found
 slab_nomerge                            |cmdline|            |   kspp   | self_protection  | OK: CONFIG_SLAB_MERGE_DEFAULT "is not set"
 iommu.strict                            |cmdline|     1      |   kspp   | self_protection  | FAIL: not found
 iommu.passthrough                       |cmdline|     0      |   kspp   | self_protection  | OK: CONFIG_IOMMU_DEFAULT_PASSTHROUGH "is not set"
 rodata                                  |cmdline|     1      |defconfig | self_protection  | OK: rodata not found
 init_on_alloc                           |cmdline|     1      |   kspp   | self_protection  | FAIL: not found
 init_on_free                            |cmdline|     1      |   kspp   | self_protection  | FAIL: not found
 slab_nomerge                            |cmdline|            |   kspp   | self_protection  | OK: CONFIG_SLAB_MERGE_DEFAULT "is not set"
 iommu.strict                            |cmdline|     1      |   kspp   | self_protection  | FAIL: not found
 iommu.passthrough                       |cmdline|     0      |   kspp   | self_protection  | OK: CONFIG_IOMMU_DEFAULT_PASSTHROUGH "is not set"

-nokaslr                                 |cmdline| is not set |   kspp   | self_protection  | OK: not found

 hardened_usercopy                       |cmdline|     1      |   kspp   | self_protection  | OK: CONFIG_HARDENED_USERCOPY "y"
 slab_common.usercopy_fallback           |cmdline|     0      |   kspp   | self_protection  | OK: CONFIG_HARDENED_USERCOPY_FALLBACK not found
 randomize_kstack_offset                 |cmdline|     1      |   kspp   | self_protection  | OK: CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT "y"
 pti                                     |cmdline|     on     |   kspp   | self_protection  | FAIL: not found
 page_alloc.shuffle                      |cmdline|     1      |  clipos  | self_protection  | FAIL: not found
 hardened_usercopy                       |cmdline|     1      |   kspp   | self_protection  | OK: CONFIG_HARDENED_USERCOPY "y"
 slab_common.usercopy_fallback           |cmdline|     0      |   kspp   | self_protection  | OK: CONFIG_HARDENED_USERCOPY_FALLBACK not found
 randomize_kstack_offset                 |cmdline|     1      |   kspp   | self_protection  | OK: CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT "y"
 pti                                     |cmdline|     on     |   kspp   | self_protection  | FAIL: not found
 page_alloc.shuffle                      |cmdline|     1      |  clipos  | self_protection  | FAIL: not found

-nosmep                                  |cmdline| is not set |    my    | self_protection  | OK: not found
-nosmap                                  |cmdline| is not set |    my    | self_protection  | OK: not found
+spectre_v2                              |cmdline|     on     |  clipos  | self_protection  | FAIL: not found

 vsyscall                                |cmdline|    none    |   kspp   |cut_attack_surface| FAIL: not found
 debugfs                                 |cmdline|    off     |  grsec   |cut_attack_surface| FAIL: not found
 
 vsyscall                                |cmdline|    none    |   kspp   |cut_attack_surface| FAIL: not found
 debugfs                                 |cmdline|    off     |  grsec   |cut_attack_surface| FAIL: not found
 

-[+] Config check is finished: 'OK' - 94 / 'FAIL' - 99
+[+] Config check is finished: 'OK' - 97 / 'FAIL' - 101

 ```
 
 ## kconfig-hardened-check versioning
 
 ```
 
 ## kconfig-hardened-check versioning
 

-I usually update the kernel security hardening recommendations after each Linux kernel release.
+I usually update the kernel security hardening recommendations every few kernel releases.

 
 So the version of `kconfig-hardened-check` is associated with the corresponding version of the kernel.
 
 
 So the version of `kconfig-hardened-check` is associated with the corresponding version of the kernel.
 


@@ -330,15 +335,20 @@ try to install `gcc-7-plugin-dev` package, it should help.
 
 __Q:__ KSPP and CLIP OS recommend `CONFIG_PANIC_ON_OOPS=y`. Why doesn't this tool do the same?
 
 
 __Q:__ KSPP and CLIP OS recommend `CONFIG_PANIC_ON_OOPS=y`. Why doesn't this tool do the same?
 

-__A:__ I personally don't support this recommendation because it provides easy denial-of-service
-attacks for the whole system (kernel oops is not a rare situation). I think having `CONFIG_BUG` is enough here --
-if we have a kernel oops in the process context, the offending/attacking process is killed.
+__A:__ I personally don't support this recommendation because:
+  - It decreases system safety (kernel oops is still not a rare situation)
+  - It allows easier denial-of-service attacks for the whole system.
+
+I think having `CONFIG_BUG` is enough here.
+If a kernel oops happens in the process context, the offending/attacking process is killed.
+In other cases the kernel panics, which is similar to `CONFIG_PANIC_ON_OOPS=y`.

 
 <br />
 
 __Q:__ What about performance impact of these security hardening options?
 
 __A:__ Ike Devolder [@BlackIkeEagle][7] made some performance tests and described the results in [this article][8].
 
 <br />
 
 __Q:__ What about performance impact of these security hardening options?
 
 __A:__ Ike Devolder [@BlackIkeEagle][7] made some performance tests and described the results in [this article][8].

+A more detailed evaluation is in the TODO list (the issue [#66][21]).

 
 <br />
 
 
 <br />
 


@@ -385,3 +395,6 @@ I highly recommend using [spectre-meltdown-checker][13] tool maintained by Stép
 [18]: https://cateee.net/lkddb/web-lkddb/
 [19]: https://github.com/cateee/lkddb
 [20]: https://kernel.org/
 [18]: https://cateee.net/lkddb/web-lkddb/
 [19]: https://github.com/cateee/lkddb
 [20]: https://kernel.org/

+[21]: https://github.com/a13xp0p0v/kconfig-hardened-check/issues/66
+[22]: https://github.com/a13xp0p0v/kconfig-hardened-check/issues/56
+[23]: https://github.com/a13xp0p0v/kconfig-hardened-check/issues?q=label%3Akernel_maintainer_feedback