[ Upstream commit 3545deff0ec7a37de7ed9632e262598582b140e9 ]

The p_align values in PT_LOAD were ignored for static PIE executables
(i.e. ET_DYN without PT_INTERP). This is because there is no way to
request a non-fixed mmap region with a specific alignment. ET_DYN with
PT_INTERP uses a separate base address (ELF_ET_DYN_BASE) and binfmt_elf
performs the ASLR itself, which means it can also apply alignment. For
the mmap region, the address selection happens deep within the vm_mmap()
implementation (when the requested address is 0).

The earlier attempt to implement this:

  commit 9630f0d60fec ("fs/binfmt_elf: use PT_LOAD p_align values for static PIE")
  commit 925346c129da ("fs/binfmt_elf: fix PT_LOAD p_align values for loaders")

did not take into account the different base address origins, and were
eventually reverted:

  aeb7923733d1 ("revert "fs/binfmt_elf: use PT_LOAD p_align values for static PIE"")

In order to get the correct alignment from an mmap base, binfmt_elf must
perform a 0-address load first, then tear down the mapping and perform
alignment on the resulting address. Since this is slightly more overhead,
only do this when it is needed (i.e. the alignment is not the default
ELF alignment). This does, however, have the benefit of being able to
use MAP_FIXED_NOREPLACE, to avoid potential collisions.

With this fixed, enable the static PIE self tests again.

Reported-by: H.J. Lu <hjl.tools@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=215275
Link: https://lore.kernel.org/r/20240508173149.677910-3-keescook@chromium.org
Signed-off-by: Kees Cook <kees@kernel.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit b57a2907c9d96c56494ef25f8ec821cd0b355dd6 ]

After commit 4d1cd3b2c5c1 ("tools/testing/selftests/exec: fix link
error"), the load address alignment tests tried to build statically.
This was silently ignored in some cases. However, after attempting to
further fix the build by switching to "-static-pie", the test started
failing. This appears to be due to non-PT_INTERP ET_DYN execs ("static
PIE") not doing alignment correctly, which remains unfixed[1]. See commit
aeb7923733d1 ("revert "fs/binfmt_elf: use PT_LOAD p_align values for
static PIE"") for more details.

Provide rules to build both static and non-static PIE binaries, improve
debug reporting, and perform several test steps instead of a single
all-or-nothing test. However, do not actually enable static-pie tests;
alignment specification is only supported for ET_DYN with PT_INTERP
("regular PIE").

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215275 [1]
Link: https://lore.kernel.org/r/20240508173149.677910-1-keescook@chromium.org
Signed-off-by: Kees Cook <kees@kernel.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit c4095067736b7ed50316a2bc7c9577941e87ad45 ]

Conform the layout, informational and status messages to TAP. No
functional change is intended other than the layout of output messages.

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/r/20240304155928.1818928-2-usama.anjum@collabora.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>

Pull Kselftest updates from Shuah Khan:
 "Several build and cleanup fixes:

   - removing obsolete config options

   - removing dependency on internal kernel macros

   - adding config options

   - several build fixes related to headers and install paths"

* tag 'linux-kselftest-next-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (22 commits)
  selftests: Fix build when $(O) points to a relative path
  selftests: netfilter: fix a build error on openSUSE
  selftests: kvm: add generated file to the .gitignore
  selftests/exec: add generated files to .gitignore
  selftests: add kselftest_install to .gitignore
  selftests/rtc: continuously read RTC in a loop for 30s
  selftests/lkdtm: Add UBSAN config
  selftests/lkdtm: Remove dead config option
  selftests/exec: Rename file binfmt_script to binfmt_script.py
  selftests: Use -isystem instead of -I to include headers
  selftests: vm: remove dependecy from internal kernel macros
  selftests: vm: Add the uapi headers include variable
  selftests: mptcp: Add the uapi headers include variable
  selftests: net: Add the uapi headers include variable
  selftests: landlock: Add the uapi headers include variable
  selftests: kvm: Add the uapi headers include variable
  selftests: futex: Add the uapi headers include variable
  selftests: Correct the headers install path
  selftests: Add and export a kernel uapi headers path
  selftests: set the BUILD variable to absolute path
  ...

Pull execve updates from Kees Cook:
 "Execve and binfmt updates.

  Eric and I have stepped up to be the active maintainers of this area,
  so here's our first collection. The bulk of the work was in coredump
  handling fixes; additional details are noted below:

   - Handle unusual AT_PHDR offsets (Akira Kawata)

   - Fix initial mapping size when PT_LOADs are not ordered (Alexey
     Dobriyan)

   - Move more code under CONFIG_COREDUMP (Alexey Dobriyan)

   - Fix missing mmap_lock in file_files_note (Eric W. Biederman)

   - Remove a.out support for alpha and m68k (Eric W. Biederman)

   - Include first pages of non-exec ELF libraries in coredump (Jann
     Horn)

   - Don't write past end of notes for regset gap in coredump (Rick
     Edgecombe)

   - Comment clean-ups (Tom Rix)

   - Force single empty string when argv is empty (Kees Cook)

   - Add NULL argv selftest (Kees Cook)

   - Properly redefine PT_GNU_* in terms of PT_LOOS (Kees Cook)

   - MAINTAINERS: Update execve entry with tree (Kees Cook)

   - Introduce initial KUnit testing for binfmt_elf (Kees Cook)"

* tag 'execve-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  binfmt_elf: Don't write past end of notes for regset gap
  a.out: Stop building a.out/osf1 support on alpha and m68k
  coredump: Don't compile flat_core_dump when coredumps are disabled
  coredump: Use the vma snapshot in fill_files_note
  coredump/elf: Pass coredump_params into fill_note_info
  coredump: Remove the WARN_ON in dump_vma_snapshot
  coredump: Snapshot the vmas in do_coredump
  coredump: Move definition of struct coredump_params into coredump.h
  binfmt_elf: Introduce KUnit test
  ELF: Properly redefine PT_GNU_* in terms of PT_LOOS
  MAINTAINERS: Update execve entry with more details
  exec: cleanup comments
  fs/binfmt_elf: Refactor load_elf_binary function
  fs/binfmt_elf: Fix AT_PHDR for unusual ELF files
  binfmt: move more stuff undef CONFIG_COREDUMP
  selftests/exec: Test for empty string on NULL argv
  exec: Force single empty string when argv is empty
  coredump: Also dump first pages of non-executable ELF libraries
  ELF: fix overflow in total mapping size calculation

Add generated files non-regular and null-argv to .gitignore file.

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Test for the NULL argv argument producing a single empty string on exec.

Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/lkml/20220201011637.2457646-1-keescook@chromium.org

Rename file for readability purpose. Update its usage and references.

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

non-regular file needs to be compiled and then copied to the output
directory. Remove it from TEST_PROGS and add it to TEST_GEN_PROGS. This
removes error thrown by rsync when non-regular object isn't found:

rsync: [sender] link_stat "/linux/tools/testing/selftests/exec/non-regular" failed: No such file or directory (2)
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1333) [sender=3.2.3]

Fixes: 0f71241a8e32 ("selftests/exec: add file type errno tests")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

pipe named FIFO special file is being created in execveat.c to perform
some tests. Makefile doesn't need to do anything with the pipe. When it
isn't found, Makefile generates the following build error:

make: *** No rule to make target
'../tools/testing/selftests/exec/pipe', needed by 'all'.  Stop.

pipe is created and removed during test run-time.

Amended change log to add pipe remove info:
Shuah Khan <skhan@linuxfoundation.org>

Fixes: 61016db15b8e ("selftests/exec: Verify execve of non-regular files fail")
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>