From: David Hildenbrand david@redhat.com
alloc_anon_secure_inode() returns an inode after running checks in security_inode_init_security_anon().
Also refactor secretmem's file creation process to use the new function.
Signed-off-by: David Hildenbrand david@redhat.com Signed-off-by: Ackerley Tng ackerleytng@google.com Signed-off-by: Ryan Afranji afranji@google.com --- fs/anon_inodes.c | 23 ++++++++++++++++------- include/linux/fs.h | 13 +++++++------ mm/secretmem.c | 9 +-------- 3 files changed, 24 insertions(+), 21 deletions(-)
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c index 583ac81669c2..0ce28959c43a 100644 --- a/fs/anon_inodes.c +++ b/fs/anon_inodes.c @@ -55,17 +55,20 @@ static struct file_system_type anon_inode_fs_type = { .kill_sb = kill_anon_super, };
-static struct inode *anon_inode_make_secure_inode( - const char *name, - const struct inode *context_inode) +static struct inode *anon_inode_make_secure_inode(struct super_block *s, + const char *name, const struct inode *context_inode, + bool fs_internal) { struct inode *inode; int error;
- inode = alloc_anon_inode(anon_inode_mnt->mnt_sb); + inode = alloc_anon_inode(s); if (IS_ERR(inode)) return inode; - inode->i_flags &= ~S_PRIVATE; + + if (!fs_internal) + inode->i_flags &= ~S_PRIVATE; + error = security_inode_init_security_anon(inode, &QSTR(name), context_inode); if (error) { @@ -75,6 +78,12 @@ static struct inode *anon_inode_make_secure_inode( return inode; }
+struct inode *alloc_anon_secure_inode(struct super_block *s, const char *name) +{ + return anon_inode_make_secure_inode(s, name, NULL, true); +} +EXPORT_SYMBOL_GPL(alloc_anon_secure_inode); + static struct file *__anon_inode_getfile(const char *name, const struct file_operations *fops, void *priv, int flags, @@ -88,7 +97,8 @@ static struct file *__anon_inode_getfile(const char *name, return ERR_PTR(-ENOENT);
if (make_inode) { - inode = anon_inode_make_secure_inode(name, context_inode); + inode = anon_inode_make_secure_inode(anon_inode_mnt->mnt_sb, + name, context_inode, false); if (IS_ERR(inode)) { file = ERR_CAST(inode); goto err; @@ -318,4 +328,3 @@ static int __init anon_inode_init(void) }
fs_initcall(anon_inode_init); - diff --git a/include/linux/fs.h b/include/linux/fs.h index 016b0fe1536e..8eeef9a7fe07 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -309,7 +309,7 @@ struct iattr { */ #define FILESYSTEM_MAX_STACK_DEPTH 2
-/** +/** * enum positive_aop_returns - aop return codes with specific semantics * * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has @@ -319,7 +319,7 @@ struct iattr { * be a candidate for writeback again in the near * future. Other callers must be careful to unlock * the page if they get this return. Returned by - * writepage(); + * writepage(); * * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has * unlocked it and the page might have been truncated. @@ -1141,8 +1141,8 @@ struct file *get_file_active(struct file **f);
#define MAX_NON_LFS ((1UL<<31) - 1)
-/* Page cache limit. The filesystems should put that into their s_maxbytes - limits, otherwise bad things can happen in VM. */ +/* Page cache limit. The filesystems should put that into their s_maxbytes + limits, otherwise bad things can happen in VM. */ #if BITS_PER_LONG==32 #define MAX_LFS_FILESIZE ((loff_t)ULONG_MAX << PAGE_SHIFT) #elif BITS_PER_LONG==64 @@ -2607,7 +2607,7 @@ int sync_inode_metadata(struct inode *inode, int wait); struct file_system_type { const char *name; int fs_flags; -#define FS_REQUIRES_DEV 1 +#define FS_REQUIRES_DEV 1 #define FS_BINARY_MOUNTDATA 2 #define FS_HAS_SUBTYPE 4 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */ @@ -3195,7 +3195,7 @@ ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos); extern ssize_t kernel_write(struct file *, const void *, size_t, loff_t *); extern ssize_t __kernel_write(struct file *, const void *, size_t, loff_t *); extern struct file * open_exec(const char *); - + /* fs/dcache.c -- generic fs support functions */ extern bool is_subdir(struct dentry *, struct dentry *); extern bool path_is_under(const struct path *, const struct path *); @@ -3550,6 +3550,7 @@ extern int simple_write_begin(struct file *file, struct address_space *mapping, extern const struct address_space_operations ram_aops; extern int always_delete_dentry(const struct dentry *); extern struct inode *alloc_anon_inode(struct super_block *); +extern struct inode *alloc_anon_secure_inode(struct super_block *, const char *); extern int simple_nosetlease(struct file *, int, struct file_lease **, void **); extern const struct dentry_operations simple_dentry_operations;
diff --git a/mm/secretmem.c b/mm/secretmem.c index 1b0a214ee558..c0e459e58cb6 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -195,18 +195,11 @@ static struct file *secretmem_file_create(unsigned long flags) struct file *file; struct inode *inode; const char *anon_name = "[secretmem]"; - int err;
- inode = alloc_anon_inode(secretmem_mnt->mnt_sb); + inode = alloc_anon_secure_inode(secretmem_mnt->mnt_sb, anon_name); if (IS_ERR(inode)) return ERR_CAST(inode);
- err = security_inode_init_security_anon(inode, &QSTR(anon_name), NULL); - if (err) { - file = ERR_PTR(err); - goto err_free_inode; - } - file = alloc_file_pseudo(inode, secretmem_mnt, "secretmem", O_RDWR, &secretmem_fops); if (IS_ERR(file))