BMC/Intel-BMC/linux.git/fs/namei.c, branch dev-5.10-intel

LOOKUP_MOUNTPOINT: we are cleaning "jumped" flag too late

2021-04-14T06:41:58+00:00

commit 4f0ed93fb92d3528c73c80317509df3f800a222b upstream. That (and traversals in case of umount .) should be done before complete_walk(). Either a braino or mismerge damage on queue reorders - either way, I should've spotted that much earlier. Fucked-up-by: Al Viro X-Paperbag: Brown Fixes: 161aff1d93ab "LOOKUP_MOUNTPOINT: fold path_mountpointat() into path_lookupat()" Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

fs: make unlazy_walk() error handling consistent

2021-03-07T11:34:11+00:00

[ Upstream commit e36cffed20a324e116f329a94061ae30dd26fb51 ] Most callers check for non-zero return, and assume it's -ECHILD (which it always will be). One caller uses the actual error return. Clean this up and make it fully consistent, by having unlazy_walk() return a bool instead. Rename it to try_to_unlazy() and return true on success, and failure on error. That's easier to read. No functional changes in this patch. Cc: Al Viro Signed-off-by: Jens Axboe Signed-off-by: Al Viro Signed-off-by: Sasha Levin

Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2020-10-24T19:26:05+00:00

Pull misc vfs updates from Al Viro: "Assorted stuff all over the place (the largest group here is Christoph's stat cleanups)" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: remove KSTAT_QUERY_FLAGS fs: remove vfs_stat_set_lookup_flags fs: move vfs_fstatat out of line fs: implement vfs_stat and vfs_lstat in terms of vfs_fstatat fs: remove vfs_statx_fd fs: omfs: use kmemdup() rather than kmalloc+memcpy [PATCH] reduce boilerplate in fsid handling fs: Remove duplicated flag O_NDELAY occurring twice in VALID_OPEN_FLAGS selftests: mount: add nosymfollow tests Add a "nosymfollow" mount option.

fs: remove the unused SB_I_MULTIROOT flag

2020-09-24T19:43:38+00:00

The last user of SB_I_MULTIROOT is disappeared with commit f2aedb713c28 ("NFS: Add fs_context support.") Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe

Add a "nosymfollow" mount option.

2020-08-27T20:06:47+00:00

For mounts that have the new "nosymfollow" option, don't follow symlinks when resolving paths. The new option is similar in spirit to the existing "nodev", "noexec", and "nosuid" options, as well as to the LOOKUP_NO_SYMLINKS resolve flag in the openat2(2) syscall. Various BSD variants have been supporting the "nosymfollow" mount option for a long time with equivalent implementations. Note that symlinks may still be created on file systems mounted with the "nosymfollow" option present. readlink() remains functional, so user space code that is aware of symlinks can still choose to follow them explicitly. Setting the "nosymfollow" mount option helps prevent privileged writers from modifying files unintentionally in case there is an unexpected link along the accessed path. The "nosymfollow" option is thus useful as a defensive measure for systems that need to deal with untrusted file systems in privileged contexts. More information on the history and motivation for this patch can be found here: https://sites.google.com/a/chromium.org/dev/chromium-os/chromiumos-design-docs/hardening-against-malicious-stateful-data#TOC-Restricting-symlink-traversal Signed-off-by: Mattias Nissler Signed-off-by: Ross Zwisler Reviewed-by: Aleksa Sarai Signed-off-by: Al Viro

exec: restore EACCES of S_ISDIR execve()

2020-08-15T02:56:56+00:00

Patch series "Fix S_ISDIR execve() errno". Fix an errno change for execve() of directories, noticed by Marc Zyngier. Along with the fix, include a regression test to avoid seeing this return in the future. This patch (of 2): The return code for attempting to execute a directory has always been EACCES. Adjust the S_ISDIR exec test to reflect the old errno instead of the general EISDIR for other kinds of "open" attempts on directories. Fixes: 633fb6ac3980 ("exec: move S_ISREG() check earlier") Reported-by: Marc Zyngier Signed-off-by: Kees Cook Signed-off-by: Andrew Morton Tested-by: Greg Kroah-Hartman Reviewed-by: Greg Kroah-Hartman Link: http://lkml.kernel.org/r/20200813231723.2725102-2-keescook@chromium.org Link: https://lore.kernel.org/lkml/20200813151305.6191993b@why Signed-off-by: Linus Torvalds

Merge branch 'akpm' (patches from Andrew)

2020-08-12T18:24:12+00:00

Merge more updates from Andrew Morton: - most of the rest of MM (memcg, hugetlb, vmscan, proc, compaction, mempolicy, oom-kill, hugetlbfs, migration, thp, cma, util, memory-hotplug, cleanups, uaccess, migration, gup, pagemap), - various other subsystems (alpha, misc, sparse, bitmap, lib, bitops, checkpatch, autofs, minix, nilfs, ufs, fat, signals, kmod, coredump, exec, kdump, rapidio, panic, kcov, kgdb, ipc). * emailed patches from Andrew Morton : (164 commits) mm/gup: remove task_struct pointer for all gup code mm: clean up the last pieces of page fault accountings mm/xtensa: use general page fault accounting mm/x86: use general page fault accounting mm/sparc64: use general page fault accounting mm/sparc32: use general page fault accounting mm/sh: use general page fault accounting mm/s390: use general page fault accounting mm/riscv: use general page fault accounting mm/powerpc: use general page fault accounting mm/parisc: use general page fault accounting mm/openrisc: use general page fault accounting mm/nios2: use general page fault accounting mm/nds32: use general page fault accounting mm/mips: use general page fault accounting mm/microblaze: use general page fault accounting mm/m68k: use general page fault accounting mm/ia64: use general page fault accounting mm/hexagon: use general page fault accounting mm/csky: use general page fault accounting ...

exec: move path_noexec() check earlier

2020-08-12T17:58:01+00:00

The path_noexec() check, like the regular file check, was happening too late, letting LSMs see impossible execve()s. Check it earlier as well in may_open() and collect the redundant fs/exec.c path_noexec() test under the same robustness comment as the S_ISREG() check. My notes on the call path, and related arguments, checks, etc: do_open_execat() struct open_flags open_exec_flags = { .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, .acc_mode = MAY_EXEC, ... do_filp_open(dfd, filename, open_flags) path_openat(nameidata, open_flags, flags) file = alloc_empty_file(open_flags, current_cred()); do_open(nameidata, file, open_flags) may_open(path, acc_mode, open_flag) /* new location of MAY_EXEC vs path_noexec() test */ inode_permission(inode, MAY_OPEN | acc_mode) security_inode_permission(inode, acc_mode) vfs_open(path, file) do_dentry_open(file, path->dentry->d_inode, open) security_file_open(f) open() /* old location of path_noexec() test */ Signed-off-by: Kees Cook Signed-off-by: Andrew Morton Cc: Alexander Viro Cc: Aleksa Sarai Cc: Christian Brauner Cc: Dmitry Vyukov Cc: Eric Biggers Cc: Tetsuo Handa Link: http://lkml.kernel.org/r/20200605160013.3954297-4-keescook@chromium.org Signed-off-by: Linus Torvalds

exec: move S_ISREG() check earlier

2020-08-12T17:58:01+00:00

The execve(2)/uselib(2) syscalls have always rejected non-regular files. Recently, it was noticed that a deadlock was introduced when trying to execute pipes, as the S_ISREG() test was happening too late. This was fixed in commit 73601ea5b7b1 ("fs/open.c: allow opening only regular files during execve()"), but it was added after inode_permission() had already run, which meant LSMs could see bogus attempts to execute non-regular files. Move the test into the other inode type checks (which already look for other pathological conditions[1]). Since there is no need to use FMODE_EXEC while we still have access to "acc_mode", also switch the test to MAY_EXEC. Also include a comment with the redundant S_ISREG() checks at the end of execve(2)/uselib(2) to note that they are present to avoid any mistakes. My notes on the call path, and related arguments, checks, etc: do_open_execat() struct open_flags open_exec_flags = { .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, .acc_mode = MAY_EXEC, ... do_filp_open(dfd, filename, open_flags) path_openat(nameidata, open_flags, flags) file = alloc_empty_file(open_flags, current_cred()); do_open(nameidata, file, open_flags) may_open(path, acc_mode, open_flag) /* new location of MAY_EXEC vs S_ISREG() test */ inode_permission(inode, MAY_OPEN | acc_mode) security_inode_permission(inode, acc_mode) vfs_open(path, file) do_dentry_open(file, path->dentry->d_inode, open) /* old location of FMODE_EXEC vs S_ISREG() test */ security_file_open(f) open() [1] https://lore.kernel.org/lkml/202006041910.9EF0C602@keescook/ Signed-off-by: Kees Cook Signed-off-by: Andrew Morton Cc: Aleksa Sarai Cc: Alexander Viro Cc: Christian Brauner Cc: Dmitry Vyukov Cc: Eric Biggers Cc: Tetsuo Handa Link: http://lkml.kernel.org/r/20200605160013.3954297-3-keescook@chromium.org Signed-off-by: Linus Torvalds

fix breakage in do_rmdir()

2020-08-12T17:22:39+00:00

syzbot reported and bisected a use-after-free due to the recent init cleanups. The putname() should happen only after we'd *not* branched to retry, same as it's done in do_unlinkat(). Reported-by: syzbot+bbeb1c88016c7db4aa24@syzkaller.appspotmail.com Fixes: e24ab0ef689d "fs: push the getname from do_rmdir into the callers" Cc: Christoph Hellwig Signed-off-by: Al Viro Signed-off-by: Linus Torvalds