kernel.git/fs/binfmt_elf_fdpic.c, branch linux-6.5.y

fs: binfmt_elf_efpic: fix personality for ELF-FDPIC

2023-10-06T11:16:29Z

commit 7c3151585730b7095287be8162b846d31e6eee61 upstream. The elf-fdpic loader hard sets the process personality to either PER_LINUX_FDPIC for true elf-fdpic binaries or to PER_LINUX for normal ELF binaries (in this case they would be constant displacement compiled with -pie for example). The problem with that is that it will lose any other bits that may be in the ELF header personality (such as the "bug emulation" bits). On the ARM architecture the ADDR_LIMIT_32BIT flag is used to signify a normal 32bit binary - as opposed to a legacy 26bit address binary. This matters since start_thread() will set the ARM CPSR register as required based on this flag. If the elf-fdpic loader loses this bit the process will be mis-configured and crash out pretty quickly. Modify elf-fdpic loader personality setting so that it preserves the upper three bytes by using the SET_PERSONALITY macro to set it. This macro in the generic case sets PER_LINUX and preserves the upper bytes. Architectures can override this for their specific use case, and ARM does exactly this. The problem shows up quite easily running under qemu using the ARM architecture, but not necessarily on all types of real ARM hardware. If the underlying ARM processor does not support the legacy 26-bit addressing mode then everything will work as expected. Link: https://lkml.kernel.org/r/20230907011808.2985083-1-gerg@kernel.org Fixes: 1bde925d23547 ("fs/binfmt_elf_fdpic.c: provide NOMMU loader for regular ELF binaries") Signed-off-by: Greg Ungerer Cc: Al Viro Cc: Christian Brauner Cc: Eric W. Biederman Cc: Greg Ungerer Cc: Kees Cook Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

binfmt: Slightly simplify elf_fdpic_map_file()

2023-05-30T22:49:46Z

There is no point in initializing 'load_addr' and 'seg' here, they are both re-written just before being used below. Doing so, 'load_addr' can be moved in the #ifdef CONFIG_MMU section. Signed-off-by: Christophe JAILLET Acked-by: "Eric W. Biederman" Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/4f5e4096ad7f17716e924b5bd080e5709fc0b84b.1685290790.git.christophe.jaillet@wanadoo.fr

binfmt: Use struct_size()

2023-05-30T22:49:46Z

Use struct_size() instead of hand-writing it. It is less verbose, more robust and more informative. Signed-off-by: Christophe JAILLET Acked-by: "Eric W. Biederman" Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/53150beae5dc04dac513dba391a2e4ae8696a7f3.1685290790.git.christophe.jaillet@wanadoo.fr

coredump, vmcore: Set p_align to 4 for PT_NOTE

2023-05-16T21:32:00Z

Tools like readelf/llvm-readelf use p_align to parse a PT_NOTE program header as an array of 4-byte entries or 8-byte entries. Currently, there are workarounds[1] in place for Linux to treat p_align==0 as 4. However, it would be more appropriate to set the correct alignment so that tools do not have to rely on guesswork. FreeBSD coredumps set p_align to 4 as well. [1]: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=82ed9683ec099d8205dc499ac84febc975235af6 [2]: https://reviews.llvm.org/D150022 Signed-off-by: Fangrui Song Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230512022528.3430327-1-maskray@google.com

ELF: fix all "Elf" typos

2023-04-08T20:45:37Z

ELF is acronym and therefore should be spelled in all caps. I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like being written in the first person. Link: https://lkml.kernel.org/r/Y/3wGWQviIOkyLJW@p183 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton

elfcore: Add a cprm parameter to elf_core_extra_{phdrs,data_size}

2023-01-05T15:12:12Z

A subsequent fix for arm64 will use this parameter to parse the vma information from the snapshot created by dump_vma_snapshot() rather than traversing the vma list without the mmap_lock. Fixes: 6dd8b1a0b6cb ("arm64: mte: Dump the MTE tags in the core file") Cc: # 5.18.x Signed-off-by: Catalin Marinas Reported-by: Seth Jenkins Suggested-by: Seth Jenkins Cc: Will Deacon Cc: Eric Biederman Cc: Kees Cook Link: https://lore.kernel.org/r/20221222181251.1345752-3-catalin.marinas@arm.com Signed-off-by: Will Deacon

binfmt: Fix error return code in load_elf_fdpic_binary()

2022-12-02T03:15:52Z

Fix to return a negative error code from create_elf_fdpic_tables() instead of 0. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Wang Yufen Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/1669945261-30271-1-git-send-email-wangyufen@huawei.com

binfmt: Fix whitespace issues

2022-10-25T22:17:23Z

Fix the annoying whitespace issues that have been following these files around for years. Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Kees Cook Acked-by: Christian Brauner (Microsoft) Link: https://lore.kernel.org/r/20221018071350.never.230-kees@kernel.org

coredump: Snapshot the vmas in do_coredump

2022-03-08T18:55:29Z

Move the call of dump_vma_snapshot and kvfree(vma_meta) out of the individual coredump routines into do_coredump itself. This makes the code less error prone and easier to maintain. Make the vma snapshot available to the coredump routines in struct coredump_params. This makes it easier to change and update what is captures in the vma snapshot and will be needed for fixing fill_file_notes. Reviewed-by: Jann Horn Reviewed-by: Kees Cook Signed-off-by: "Eric W. Biederman"

binfmt: move more stuff undef CONFIG_COREDUMP

2022-03-02T00:16:27Z

struct linux_binfmt::core_dump and struct min_coredump::min_coredump are used under CONFIG_COREDUMP only. Shrink those embedded configs a bit. Signed-off-by: Alexey Dobriyan Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/YglbIFyN+OtwVyjW@localhost.localdomain