Al, will you send this patch to 5.3-rcX via vfs.git tree? On 2019/07/23 13:16, John Johansen wrote: > On 7/22/19 3:12 AM, Tetsuo Handa wrote: >> I did not see AppArmor patch for this problem in 5.3-rc1. >> John, are you OK with this patch for 5.2-stable and 5.3 ? >> > yes, I have some larger mount rework and clean-up to do and an apparmor > patch for this is waiting on that. Looking at the thread I am wondering > where my previous reply is, probably lost in a mail client crash, I have > had a few of those lately. > > Acked-by: John Johansen <john.johansen@xxxxxxxxxxxxx> > > >> On 2019/07/09 19:51, Tetsuo Handa wrote: >>> For now, can we apply this patch for 5.2-stable ? >>> >>> >>> >From dd62fab0592e02580fd5a34222a2d11bfc179f61 Mon Sep 17 00:00:00 2001 >>> From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> >>> Date: Tue, 9 Jul 2019 19:05:49 +0900 >>> Subject: [PATCH] LSM: Disable move_mount() syscall when TOMOYO or AppArmor is enabled. >>> >>> Commit 2db154b3ea8e14b0 ("vfs: syscall: Add move_mount(2) to move mounts >>> around") introduced security_move_mount() LSM hook, but we missed that >>> TOMOYO and AppArmor did not implement hooks for checking move_mount(2). >>> For pathname based access controls like TOMOYO and AppArmor, unchecked >>> mount manipulation is not acceptable. Therefore, until TOMOYO and AppArmor >>> implement hooks, in order to avoid unchecked mount manipulation, pretend >>> as if move_mount(2) is unavailable when either TOMOYO or AppArmor is >>> enabled. >>> >>> Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> >>> Fixes: 2db154b3ea8e14b0 ("vfs: syscall: Add move_mount(2) to move mounts around") >>> Cc: stable@xxxxxxxxxxxxxxx # 5.2 >>> --- >>> include/linux/lsm_hooks.h | 6 ++++++ >>> security/apparmor/lsm.c | 1 + >>> security/tomoyo/tomoyo.c | 1 + >>> 3 files changed, 8 insertions(+) >>> >>> diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h >>> index 47f58cf..cd411b7 100644 >>> --- a/include/linux/lsm_hooks.h >>> +++ b/include/linux/lsm_hooks.h >>> @@ -2142,4 +2142,10 @@ static inline void security_delete_hooks(struct security_hook_list *hooks, >>> >>> extern int lsm_inode_alloc(struct inode *inode); >>> >>> +static inline int no_move_mount(const struct path *from_path, >>> + const struct path *to_path) >>> +{ >>> + return -ENOSYS; >>> +} >>> + >>> #endif /* ! __LINUX_LSM_HOOKS_H */ >>> diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c >>> index ec3a928..5cdf63b 100644 >>> --- a/security/apparmor/lsm.c >>> +++ b/security/apparmor/lsm.c >>> @@ -1158,6 +1158,7 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = { >>> LSM_HOOK_INIT(capable, apparmor_capable), >>> >>> LSM_HOOK_INIT(sb_mount, apparmor_sb_mount), >>> + LSM_HOOK_INIT(move_mount, no_move_mount), >>> LSM_HOOK_INIT(sb_umount, apparmor_sb_umount), >>> LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot), >>> >>> diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c >>> index 716c92e..be1b1a1 100644 >>> --- a/security/tomoyo/tomoyo.c >>> +++ b/security/tomoyo/tomoyo.c >>> @@ -558,6 +558,7 @@ static void tomoyo_task_free(struct task_struct *task) >>> LSM_HOOK_INIT(path_chown, tomoyo_path_chown), >>> LSM_HOOK_INIT(path_chroot, tomoyo_path_chroot), >>> LSM_HOOK_INIT(sb_mount, tomoyo_sb_mount), >>> + LSM_HOOK_INIT(move_mount, no_move_mount), >>> LSM_HOOK_INIT(sb_umount, tomoyo_sb_umount), >>> LSM_HOOK_INIT(sb_pivotroot, tomoyo_sb_pivotroot), >>> LSM_HOOK_INIT(socket_bind, tomoyo_socket_bind), >>> >> > >