kernel/linux.git/security/tomoyo, branch v5.10.28

tomoyo: recognize kernel threads correctly

2021-03-09T10:11:15+00:00

commit 9c83465f3245c2faa82ffeb7016f40f02bfaa0ad upstream. Commit db68ce10c4f0a27c ("new helper: uaccess_kernel()") replaced segment_eq(get_fs(), KERNEL_DS) with uaccess_kernel(). But the correct method for tomoyo to check whether current is a kernel thread in order to assume that kernel threads are privileged for socket operations was (current->flags & PF_KTHREAD). Now that uaccess_kernel() became 0 on x86, tomoyo has to fix this problem. Do like commit 942cb357ae7d9249 ("Smack: Handle io_uring kernel thread privileges") does. Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman

tomoyo: ignore data race while checking quota

2021-03-07T11:34:05+00:00

commit 5797e861e402fff2bedce4ec8b7c89f4248b6073 upstream. syzbot is reporting that tomoyo's quota check is racy [1]. But this check is tolerant of some degree of inaccuracy. Thus, teach KCSAN to ignore this data race. [1] https://syzkaller.appspot.com/bug?id=999533deec7ba6337f8aa25d8bd1a4d5f7e50476 Reported-by: syzbot Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman

tomoyo: Loosen pathname/domainname validation.

2020-10-12T10:53:34+00:00

Since commit e2dc9bf3f5275ca3 ("umd: Transform fork_usermode_blob into fork_usermode_driver") started calling execve() on a program written in a local mount which is not connected to mount tree, tomoyo_realpath_from_path() started returning a pathname in "$fsname:/$pathname" format which violates TOMOYO's domainname rule that it must start with "<$namespace>" followed by zero or more repetitions of pathnames which start with '/'. Since $fsname must not contain '.' since commit 79c0b2df79eb56fc ("add filesystem subtype support"), tomoyo_correct_path() can recognize a token which appears '/' before '.' appears (e.g. proc:/self/exe ) as a pathname while rejecting a token which appears '.' before '/' appears (e.g. exec.realpath="/bin/bash" ) as a condition parameter. Therefore, accept domainnames which contain pathnames which do not start with '/' but contain '/' before '.' (e.g. tmpfs:/bpfilter_umh ). Signed-off-by: Tetsuo Handa

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

mm/gup: remove task_struct pointer for all gup code

2020-08-12T17:58:04+00:00

After the cleanup of page fault accounting, gup does not need to pass task_struct around any more. Remove that parameter in the whole gup stack. Signed-off-by: Peter Xu Signed-off-by: Andrew Morton Reviewed-by: John Hubbard Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com Signed-off-by: Linus Torvalds

exec: Implement kernel_execve

2020-07-21T13:24:52+00:00

To allow the kernel not to play games with set_fs to call exec implement kernel_execve. The function kernel_execve takes pointers into kernel memory and copies the values pointed to onto the new userspace stack. The calls with arguments from kernel space of do_execve are replaced with calls to kernel_execve. The calls do_execve and do_execveat are made static as there are now no callers outside of exec. The comments that mention do_execve are updated to refer to kernel_execve or execve depending on the circumstances. In addition to correcting the comments, this makes it easy to grep for do_execve and verify it is not used. Inspired-by: https://lkml.kernel.org/r/20200627072704.2447163-1-hch@lst.de Reviewed-by: Kees Cook Link: https://lkml.kernel.org/r/87wo365ikj.fsf@x220.int.ebiederm.org Signed-off-by: "Eric W. Biederman"

treewide: replace '---help---' in Kconfig files with 'help'

2020-06-13T16:57:21+00:00

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada

Merge branch 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2020-06-04T21:07:08+00:00

Pull execve updates from Eric Biederman: "Last cycle for the Nth time I ran into bugs and quality of implementation issues related to exec that could not be easily be fixed because of the way exec is implemented. So I have been digging into exec and cleanup up what I can. I don't think I have exec sorted out enough to fix the issues I started with but I have made some headway this cycle with 4 sets of changes. - promised cleanups after introducing exec_update_mutex - trivial cleanups for exec - control flow simplifications - remove the recomputation of bprm->cred The net result is code that is a bit easier to understand and work with and a decrease in the number of lines of code (if you don't count the added tests)" * 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (24 commits) exec: Compute file based creds only once exec: Add a per bprm->file version of per_clear binfmt_elf_fdpic: fix execfd build regression selftests/exec: Add binfmt_script regression test exec: Remove recursion from search_binary_handler exec: Generic execfd support exec/binfmt_script: Don't modify bprm->buf and then return -ENOEXEC exec: Move the call of prepare_binprm into search_binary_handler exec: Allow load_misc_binary to call prepare_binprm unconditionally exec: Convert security_bprm_set_creds into security_bprm_repopulate_creds exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds exec: Teach prepare_exec_creds how exec treats uids & gids exec: Set the point of no return sooner exec: Move handling of the point of no return to the top level exec: Run sync_mm_rss before taking exec_update_mutex exec: Fix spelling of search_binary_handler in a comment exec: Move the comment from above de_thread to above unshare_sighand exec: Rename flush_old_exec begin_new_exec exec: Move most of setup_new_exec into flush_old_exec exec: In setup_new_exec cache current in the local variable me ...

Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2020-06-04T20:54:34+00:00

Pull proc updates from Eric Biederman: "This has four sets of changes: - modernize proc to support multiple private instances - ensure we see the exit of each process tid exactly - remove has_group_leader_pid - use pids not tasks in posix-cpu-timers lookup Alexey updated proc so each mount of proc uses a new superblock. This allows people to actually use mount options with proc with no fear of messing up another mount of proc. Given the kernel's internal mounts of proc for things like uml this was a real problem, and resulted in Android's hidepid mount options being ignored and introducing security issues. The rest of the changes are small cleanups and fixes that came out of my work to allow this change to proc. In essence it is swapping the pids in de_thread during exec which removes a special case the code had to handle. Then updating the code to stop handling that special case" * 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: proc: proc_pid_ns takes super_block as an argument remove the no longer needed pid_alive() check in __task_pid_nr_ns() posix-cpu-timers: Replace __get_task_for_clock with pid_for_clock posix-cpu-timers: Replace cpu_timer_pid_type with clock_pid_type posix-cpu-timers: Extend rcu_read_lock removing task_struct references signal: Remove has_group_leader_pid exec: Remove BUG_ON(has_group_leader_pid) posix-cpu-timer: Unify the now redundant code in lookup_task posix-cpu-timer: Tidy up group_leader logic in lookup_task proc: Ensure we see the exit of each process tid exactly once rculist: Add hlists_swap_heads_rcu proc: Use PIDTYPE_TGID in next_tgid Use proc_pid_ns() to get pid_namespace from the proc superblock proc: use named enums for better readability proc: use human-readable values for hidepid docs: proc: add documentation for "hidepid=4" and "subset=pid" options and new mount behavior proc: add option to mount only a pids subset proc: instantiate only pids that we can ptrace on 'hidepid=4' mount option proc: allow to mount many instances of proc in one pid namespace proc: rename struct proc_fs_info to proc_fs_opts

Merge tag 'tomoyo-pr-20200601' of git://git.osdn.net/gitroot/tomoyo/tomoyo-test1

2020-06-03T00:12:07+00:00

Pull tomoyo update from Tetsuo Handa: "One patch for suppressing coccicheck's warning" * tag 'tomoyo-pr-20200601' of git://git.osdn.net/gitroot/tomoyo/tomoyo-test1: tomoyo: use true for bool variable