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Diffstat (limited to 'mm/secretmem.c')
-rw-r--r--mm/secretmem.c106
1 files changed, 42 insertions, 64 deletions
diff --git a/mm/secretmem.c b/mm/secretmem.c
index 04c3ac9448a1..edf111e0a1bb 100644
--- a/mm/secretmem.c
+++ b/mm/secretmem.c
@@ -35,7 +35,7 @@
#define SECRETMEM_MODE_MASK (0x0)
#define SECRETMEM_FLAGS_MASK SECRETMEM_MODE_MASK
-static bool secretmem_enable __ro_after_init;
+static bool secretmem_enable __ro_after_init = 1;
module_param_named(enable, secretmem_enable, bool, 0400);
MODULE_PARM_DESC(secretmem_enable,
"Enable secretmem and memfd_secret(2) system call");
@@ -54,7 +54,7 @@ static vm_fault_t secretmem_fault(struct vm_fault *vmf)
pgoff_t offset = vmf->pgoff;
gfp_t gfp = vmf->gfp_mask;
unsigned long addr;
- struct page *page;
+ struct folio *folio;
vm_fault_t ret;
int err;
@@ -64,31 +64,31 @@ static vm_fault_t secretmem_fault(struct vm_fault *vmf)
filemap_invalidate_lock_shared(mapping);
retry:
- page = find_lock_page(mapping, offset);
- if (!page) {
- page = alloc_page(gfp | __GFP_ZERO);
- if (!page) {
+ folio = filemap_lock_folio(mapping, offset);
+ if (IS_ERR(folio)) {
+ folio = folio_alloc(gfp | __GFP_ZERO, 0);
+ if (!folio) {
ret = VM_FAULT_OOM;
goto out;
}
- err = set_direct_map_invalid_noflush(page);
+ err = set_direct_map_invalid_noflush(folio_page(folio, 0));
if (err) {
- put_page(page);
+ folio_put(folio);
ret = vmf_error(err);
goto out;
}
- __SetPageUptodate(page);
- err = add_to_page_cache_lru(page, mapping, offset, gfp);
+ __folio_mark_uptodate(folio);
+ err = filemap_add_folio(mapping, folio, offset, gfp);
if (unlikely(err)) {
- put_page(page);
/*
* If a split of large page was required, it
* already happened when we marked the page invalid
* which guarantees that this call won't fail
*/
- set_direct_map_default_noflush(page);
+ set_direct_map_default_noflush(folio_page(folio, 0));
+ folio_put(folio);
if (err == -EEXIST)
goto retry;
@@ -96,11 +96,11 @@ retry:
goto out;
}
- addr = (unsigned long)page_address(page);
+ addr = (unsigned long)folio_address(folio);
flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
}
- vmf->page = page;
+ vmf->page = folio_file_page(folio, vmf->pgoff);
ret = VM_FAULT_LOCKED;
out:
@@ -118,18 +118,18 @@ static int secretmem_release(struct inode *inode, struct file *file)
return 0;
}
-static int secretmem_mmap(struct file *file, struct vm_area_struct *vma)
+static int secretmem_mmap_prepare(struct vm_area_desc *desc)
{
- unsigned long len = vma->vm_end - vma->vm_start;
+ const unsigned long len = vma_desc_size(desc);
- if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
+ if ((desc->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
return -EINVAL;
- if (mlock_future_check(vma->vm_mm, vma->vm_flags | VM_LOCKED, len))
+ if (!mlock_future_ok(desc->mm, desc->vm_flags | VM_LOCKED, len))
return -EAGAIN;
- vma->vm_flags |= VM_LOCKED | VM_DONTDUMP;
- vma->vm_ops = &secretmem_vm_ops;
+ desc->vm_flags |= VM_LOCKED | VM_DONTDUMP;
+ desc->vm_ops = &secretmem_vm_ops;
return 0;
}
@@ -141,7 +141,7 @@ bool vma_is_secretmem(struct vm_area_struct *vma)
static const struct file_operations secretmem_fops = {
.release = secretmem_release,
- .mmap = secretmem_mmap,
+ .mmap_prepare = secretmem_mmap_prepare,
};
static int secretmem_migrate_folio(struct address_space *mapping,
@@ -152,7 +152,7 @@ static int secretmem_migrate_folio(struct address_space *mapping,
static void secretmem_free_folio(struct folio *folio)
{
- set_direct_map_default_noflush(&folio->page);
+ set_direct_map_default_noflush(folio_page(folio, 0));
folio_zero_segment(folio, 0, folio_size(folio));
}
@@ -162,7 +162,7 @@ const struct address_space_operations secretmem_aops = {
.migrate_folio = secretmem_migrate_folio,
};
-static int secretmem_setattr(struct user_namespace *mnt_userns,
+static int secretmem_setattr(struct mnt_idmap *idmap,
struct dentry *dentry, struct iattr *iattr)
{
struct inode *inode = d_inode(dentry);
@@ -175,7 +175,7 @@ static int secretmem_setattr(struct user_namespace *mnt_userns,
if ((ia_valid & ATTR_SIZE) && inode->i_size)
ret = -EINVAL;
else
- ret = simple_setattr(mnt_userns, dentry, iattr);
+ ret = simple_setattr(idmap, dentry, iattr);
filemap_invalidate_unlock(mapping);
@@ -190,24 +190,16 @@ static struct vfsmount *secretmem_mnt;
static struct file *secretmem_file_create(unsigned long flags)
{
- struct file *file = ERR_PTR(-ENOMEM);
+ struct file *file;
struct inode *inode;
const char *anon_name = "[secretmem]";
- const struct qstr qname = QSTR_INIT(anon_name, strlen(anon_name));
- int err;
- inode = alloc_anon_inode(secretmem_mnt->mnt_sb);
+ inode = anon_inode_make_secure_inode(secretmem_mnt->mnt_sb, anon_name, NULL);
if (IS_ERR(inode))
return ERR_CAST(inode);
- err = security_inode_init_security_anon(inode, &qname, NULL);
- if (err) {
- file = ERR_PTR(err);
- goto err_free_inode;
- }
-
file = alloc_file_pseudo(inode, secretmem_mnt, "secretmem",
- O_RDWR, &secretmem_fops);
+ O_RDWR | O_LARGEFILE, &secretmem_fops);
if (IS_ERR(file))
goto err_free_inode;
@@ -221,6 +213,8 @@ static struct file *secretmem_file_create(unsigned long flags)
inode->i_mode |= S_IFREG;
inode->i_size = 0;
+ atomic_inc(&secretmem_users);
+
return file;
err_free_inode:
@@ -230,13 +224,10 @@ err_free_inode:
SYSCALL_DEFINE1(memfd_secret, unsigned int, flags)
{
- struct file *file;
- int fd, err;
-
- /* make sure local flags do not confict with global fcntl.h */
+ /* make sure local flags do not conflict with global fcntl.h */
BUILD_BUG_ON(SECRETMEM_FLAGS_MASK & O_CLOEXEC);
- if (!secretmem_enable)
+ if (!secretmem_enable || !can_set_direct_map())
return -ENOSYS;
if (flags & ~(SECRETMEM_FLAGS_MASK | O_CLOEXEC))
@@ -244,30 +235,20 @@ SYSCALL_DEFINE1(memfd_secret, unsigned int, flags)
if (atomic_read(&secretmem_users) < 0)
return -ENFILE;
- fd = get_unused_fd_flags(flags & O_CLOEXEC);
- if (fd < 0)
- return fd;
-
- file = secretmem_file_create(flags);
- if (IS_ERR(file)) {
- err = PTR_ERR(file);
- goto err_put_fd;
- }
-
- file->f_flags |= O_LARGEFILE;
-
- atomic_inc(&secretmem_users);
- fd_install(fd, file);
- return fd;
-
-err_put_fd:
- put_unused_fd(fd);
- return err;
+ return FD_ADD(flags & O_CLOEXEC, secretmem_file_create(flags));
}
static int secretmem_init_fs_context(struct fs_context *fc)
{
- return init_pseudo(fc, SECRETMEM_MAGIC) ? 0 : -ENOMEM;
+ struct pseudo_fs_context *ctx;
+
+ ctx = init_pseudo(fc, SECRETMEM_MAGIC);
+ if (!ctx)
+ return -ENOMEM;
+
+ fc->s_iflags |= SB_I_NOEXEC;
+ fc->s_iflags |= SB_I_NODEV;
+ return 0;
}
static struct file_system_type secretmem_fs = {
@@ -278,16 +259,13 @@ static struct file_system_type secretmem_fs = {
static int __init secretmem_init(void)
{
- if (!secretmem_enable)
+ if (!secretmem_enable || !can_set_direct_map())
return 0;
secretmem_mnt = kern_mount(&secretmem_fs);
if (IS_ERR(secretmem_mnt))
return PTR_ERR(secretmem_mnt);
- /* prevent secretmem mappings from ever getting PROT_EXEC */
- secretmem_mnt->mnt_flags |= MNT_NOEXEC;
-
return 0;
}
fs_initcall(secretmem_init);