[PATCH v2 15/25] security: Introduce file_pre_free_security hook
From: Roberto Sassu <hidden>
Date: 2023-08-31 10:47:09
Also in:
keyrings, linux-fsdevel, linux-integrity, linux-nfs, lkml, selinux
Subsystem:
filesystems (vfs and infrastructure), security subsystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
From: Roberto Sassu <roberto.sassu@huawei.com> In preparation for moving IMA and EVM to the LSM infrastructure, introduce the file_pre_free_security hook. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> --- fs/file_table.c | 1 + include/linux/lsm_hook_defs.h | 1 + include/linux/security.h | 4 ++++ security/security.c | 11 +++++++++++ 4 files changed, 17 insertions(+)
diff --git a/fs/file_table.c b/fs/file_table.c
index fc7d677ff5ad..964e24120684 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c@@ -375,6 +375,7 @@ static void __fput(struct file *file) eventpoll_release(file); locks_remove_file(file); + security_file_pre_free(file); ima_file_free(file); if (unlikely(file->f_flags & FASYNC)) { if (file->f_op->fasync)
diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index 60ed33f0c80d..797f51da3f7d 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h@@ -172,6 +172,7 @@ LSM_HOOK(int, 0, kernfs_init_security, struct kernfs_node *kn_dir, struct kernfs_node *kn) LSM_HOOK(int, 0, file_permission, struct file *file, int mask) LSM_HOOK(int, 0, file_alloc_security, struct file *file) +LSM_HOOK(void, LSM_RET_VOID, file_pre_free_security, struct file *file) LSM_HOOK(void, LSM_RET_VOID, file_free_security, struct file *file) LSM_HOOK(int, 0, file_ioctl, struct file *file, unsigned int cmd, unsigned long arg)
diff --git a/include/linux/security.h b/include/linux/security.h
index a0f16511c059..7871009d59ae 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h@@ -389,6 +389,7 @@ int security_kernfs_init_security(struct kernfs_node *kn_dir, struct kernfs_node *kn); int security_file_permission(struct file *file, int mask); int security_file_alloc(struct file *file); +void security_file_pre_free(struct file *file); void security_file_free(struct file *file); int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg); int security_mmap_file(struct file *file, unsigned long prot,
@@ -985,6 +986,9 @@ static inline int security_file_alloc(struct file *file) return 0; } +static inline void security_file_pre_free(struct file *file) +{ } + static inline void security_file_free(struct file *file) { }
diff --git a/security/security.c b/security/security.c
index 3e0078b51e46..3e648aa9292c 100644
--- a/security/security.c
+++ b/security/security.c@@ -2626,6 +2626,17 @@ int security_file_alloc(struct file *file) return rc; } +/** + * security_file_pre_free() - Perform actions before freeing a file's LSM blob + * @file: the file + * + * Perform actions before the file descriptor is freed. + */ +void security_file_pre_free(struct file *file) +{ + call_void_hook(file_pre_free_security, file); +} + /** * security_file_free() - Free a file's LSM blob * @file: the file
--
2.34.1