diff options
| author | Günther Noack <gnoack3000@gmail.com> | 2022-10-18 20:22:06 +0200 |
|---|---|---|
| committer | Mickaël Salaün <mic@digikod.net> | 2022-10-19 09:01:40 +0200 |
| commit | 3350607dc5637be2563f484dcfe2fed456f3d4ff (patch) | |
| tree | fda8bd79084e26e2062fec46370c1a572b0d187f /security | |
| parent | 9abf2313adc1ca1b6180c508c25f22f9395cc780 (diff) | |
security: Create file_truncate hook from path_truncate hook
Like path_truncate, the file_truncate hook also restricts file
truncation, but is called in the cases where truncation is attempted
on an already-opened file.
This is required in a subsequent commit to handle ftruncate()
operations differently to truncate() operations.
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20221018182216.301684-2-gnoack3000@gmail.com
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Diffstat (limited to 'security')
| -rw-r--r-- | security/apparmor/lsm.c | 6 | ||||
| -rw-r--r-- | security/security.c | 5 | ||||
| -rw-r--r-- | security/tomoyo/tomoyo.c | 13 |
3 files changed, 24 insertions, 0 deletions
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index f56070270c69..be31549cfb40 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -329,6 +329,11 @@ static int apparmor_path_truncate(const struct path *path) return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR); } +static int apparmor_file_truncate(struct file *file) +{ + return apparmor_path_truncate(&file->f_path); +} + static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry, const char *old_name) { @@ -1232,6 +1237,7 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(mmap_file, apparmor_mmap_file), LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect), LSM_HOOK_INIT(file_lock, apparmor_file_lock), + LSM_HOOK_INIT(file_truncate, apparmor_file_truncate), LSM_HOOK_INIT(getprocattr, apparmor_getprocattr), LSM_HOOK_INIT(setprocattr, apparmor_setprocattr), diff --git a/security/security.c b/security/security.c index 79d82cb6e469..b55596958d0c 100644 --- a/security/security.c +++ b/security/security.c @@ -1652,6 +1652,11 @@ int security_file_open(struct file *file) return fsnotify_perm(file, MAY_OPEN); } +int security_file_truncate(struct file *file) +{ + return call_int_hook(file_truncate, 0, file); +} + int security_task_alloc(struct task_struct *task, unsigned long clone_flags) { int rc = lsm_task_alloc(task); diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c index 71e82d855ebf..af04a7b7eb28 100644 --- a/security/tomoyo/tomoyo.c +++ b/security/tomoyo/tomoyo.c @@ -135,6 +135,18 @@ static int tomoyo_path_truncate(const struct path *path) } /** + * tomoyo_file_truncate - Target for security_file_truncate(). + * + * @file: Pointer to "struct file". + * + * Returns 0 on success, negative value otherwise. + */ +static int tomoyo_file_truncate(struct file *file) +{ + return tomoyo_path_truncate(&file->f_path); +} + +/** * tomoyo_path_unlink - Target for security_path_unlink(). * * @parent: Pointer to "struct path". @@ -545,6 +557,7 @@ static struct security_hook_list tomoyo_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(bprm_check_security, tomoyo_bprm_check_security), LSM_HOOK_INIT(file_fcntl, tomoyo_file_fcntl), LSM_HOOK_INIT(file_open, tomoyo_file_open), + LSM_HOOK_INIT(file_truncate, tomoyo_file_truncate), LSM_HOOK_INIT(path_truncate, tomoyo_path_truncate), LSM_HOOK_INIT(path_unlink, tomoyo_path_unlink), LSM_HOOK_INIT(path_mkdir, tomoyo_path_mkdir), |