user/sven/linux.git/fs/exec.c, branch stable/6.2.y

Merge tag 'fs.vfsuid.conversion.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping

2022-12-13T03:20:05Z

Pull vfsuid updates from Christian Brauner: "Last cycle we introduced the vfs{g,u}id_t types and associated helpers to gain type safety when dealing with idmapped mounts. That initial work already converted a lot of places over but there were still some left, This converts all remaining places that still make use of non-type safe idmapping helpers to rely on the new type safe vfs{g,u}id based helpers. Afterwards it removes all the old non-type safe helpers" * tag 'fs.vfsuid.conversion.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: fs: remove unused idmapping helpers ovl: port to vfs{g,u}id_t and associated helpers fuse: port to vfs{g,u}id_t and associated helpers ima: use type safe idmapping helpers apparmor: use type safe idmapping helpers caps: use type safe idmapping helpers fs: use type safe idmapping helpers mnt_idmapping: add missing helpers

Merge tag 'execve-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2022-12-12T16:42:29Z

Pull execve updates from Kees Cook: "Most are small refactorings and bug fixes, but three things stand out: switching timens (which got reverted before) looks solid now, FOLL_FORCE has been removed (no failures seen yet across several weeks in -next), and some whitespace cleanups (which are long overdue). - Add timens support (when switching mm). This version has survived in -next for the entire cycle (Andrei Vagin) - Various small bug fixes, refactoring, and readability improvements (Bernd Edlinger, Rolf Eike Beer, Bo Liu, Li Zetao Liu Shixin) - Remove FOLL_FORCE for stack setup (Kees Cook) - Whitespace cleanups (Rolf Eike Beer, Kees Cook)" * tag 'execve-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: binfmt_misc: fix shift-out-of-bounds in check_special_flags binfmt: Fix error return code in load_elf_fdpic_binary() exec: Remove FOLL_FORCE for stack setup binfmt_elf: replace IS_ERR() with IS_ERR_VALUE() binfmt_elf: simplify error handling in load_elf_phdrs() binfmt_elf: fix documented return value for load_elf_phdrs() exec: simplify initial stack size expansion binfmt: Fix whitespace issues exec: Add comments on check_unsafe_exec() fs counting ELF uapi: add spaces before '{' selftests/timens: add a test for vfork+exit fs/exec: switch timens when a task gets a new mm

exec: Remove FOLL_FORCE for stack setup

2022-11-18T00:31:55Z

It does not appear that FOLL_FORCE should be needed for setting up the stack pages. They are allocated using the nascent brpm->vma, which was newly created with VM_STACK_FLAGS, which an arch can override, but they all appear to include VM_WRITE | VM_MAYWRITE. Remove FOLL_FORCE. Cc: Eric Biederman Cc: David Hildenbrand Cc: Linus Torvalds Cc: Alexander Viro Cc: linux-fsdevel@vger.kernel.org Cc: linux-mm@kvack.org Link: https://lore.kernel.org/lkml/202211171439.CDE720EAD@keescook/ Signed-off-by: Kees Cook

Merge tag 'mm-hotfixes-stable-2022-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-10-30T00:49:33Z

Pull misc hotfixes from Andrew Morton: "Eight fix pre-6.0 bugs and the remainder address issues which were introduced in the 6.1-rc merge cycle, or address issues which aren't considered sufficiently serious to warrant a -stable backport" * tag 'mm-hotfixes-stable-2022-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits) mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off region lib: maple_tree: remove unneeded initialization in mtree_range_walk() mmap: fix remap_file_pages() regression mm/shmem: ensure proper fallback if page faults mm/userfaultfd: replace kmap/kmap_atomic() with kmap_local_page() x86: fortify: kmsan: fix KMSAN fortify builds x86: asm: make sure __put_user_size() evaluates pointer once Kconfig.debug: disable CONFIG_FRAME_WARN for KMSAN by default x86/purgatory: disable KMSAN instrumentation mm: kmsan: export kmsan_copy_page_meta() mm: migrate: fix return value if all subpages of THPs are migrated successfully mm/uffd: fix vma check on userfault for wp mm: prep_compound_tail() clear page->private mm,madvise,hugetlb: fix unexpected data loss with MADV_DONTNEED on hugetlbfs mm/page_isolation: fix clang deadcode warning fs/ext4/super.c: remove unused `deprecated_msg' ipc/msg.c: fix percpu_counter use after free memory tier, sysfs: rename attribute "nodes" to "nodelist" MAINTAINERS: git://github.com -> https://github.com for nilfs2 mm/kmemleak: prevent soft lockup in kmemleak_scan()'s object iteration loops ...

mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off region

2022-10-28T20:37:23Z

lru_gen_add_mm() has been added within an IRQ-off region in the commit mentioned below. The other invocations of lru_gen_add_mm() are not within an IRQ-off region. The invocation within IRQ-off region is problematic on PREEMPT_RT because the function is using a spin_lock_t which must not be used within IRQ-disabled regions. The other invocations of lru_gen_add_mm() occur while task_struct::alloc_lock is acquired. Move lru_gen_add_mm() after interrupts are enabled and before task_unlock(). Link: https://lkml.kernel.org/r/20221026134830.711887-1-bigeasy@linutronix.de Fixes: bd74fdaea1460 ("mm: multi-gen LRU: support page table walks") Signed-off-by: Sebastian Andrzej Siewior Acked-by: Yu Zhao Cc: Al Viro Cc: "Eric W . Biederman" Cc: Kees Cook Cc: Thomas Gleixner Signed-off-by: Andrew Morton

fs: use type safe idmapping helpers

2022-10-26T08:02:34Z

We already ported most parts and filesystems over for v6.0 to the new vfs{g,u}id_t type and associated helpers for v6.0. Convert the remaining places so we can remove all the old helpers. This is a non-functional change. Reviewed-by: Seth Forshee (DigitalOcean) Signed-off-by: Christian Brauner (Microsoft)

exec: simplify initial stack size expansion

2022-10-25T22:19:48Z

I had a hard time trying to understand completely why it is using vm_end in one side of the expression and vm_start in the other one, and using something in the "if" clause that is not an exact copy of what is used below. The whole point is that the stack_size variable that was used in the "if" clause is the difference between vm_start and vm_end, which is not far away but makes this thing harder to read than it must be. Signed-off-by: Rolf Eike Beer Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/2017429.gqNitNVd0C@mobilepool36.emlix.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

exec: Add comments on check_unsafe_exec() fs counting

2022-10-25T22:17:08Z

Add some comments about what the fs counting is doing in check_unsafe_exec() and how it relates to the call graph. Specifically, we can't force an unshare of the fs because of at least Chrome: https://lore.kernel.org/lkml/86CE201B-5632-4BB7-BCF6-7CB2C2895409@chromium.org/ Cc: Eric Biederman Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Kees Cook Acked-by: Christian Brauner (Microsoft) Link: https://lore.kernel.org/r/20221018071537.never.662-kees@kernel.org

fs/exec: switch timens when a task gets a new mm

2022-10-25T22:15:52Z

Changing a time namespace requires remapping a vvar page, so we don't want to allow doing that if any other tasks can use the same mm. Currently, we install a time namespace when a task is created with a new vm. exec() is another case when a task gets a new mm and so it can switch a time namespace safely, but it isn't handled now. One more issue of the current interface is that clone() with CLONE_VM isn't allowed if the current task has unshared a time namespace (timens_for_children doesn't match the current timens). Both these issues make some inconvenience for users. For example, Alexey and Florian reported that posix_spawn() uses vfork+exec and this pattern doesn't work with time namespaces due to the both described issues. LXC needed to workaround the exec() issue by calling setns. In the commit 133e2d3e81de5 ("fs/exec: allow to unshare a time namespace on vfork+exec"), we tried to fix these issues with minimal impact on UAPI. But it adds extra complexity and some undesirable side effects. Eric suggested fixing the issues properly because here are all the reasons to suppose that there are no users that depend on the old behavior. Cc: Alexey Izbyshev Cc: Christian Brauner Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: "Eric W. Biederman" Cc: Florian Weimer Cc: Kees Cook Suggested-by: "Eric W. Biederman" Origin-author: "Eric W. Biederman" Signed-off-by: Andrei Vagin Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220921003120.209637-1-avagin@google.com