[PATCH 03/10] fs: consistently use file_has_valid_mmap_hooks() helper
From: Lorenzo Stoakes <hidden>
Date: 2025-06-16 19:35:09
Also in:
ceph-devel, intel-gfx, linux-bcachefs, linux-btrfs, linux-cifs, linux-ext4, linux-f2fs-devel, linux-fsdevel, linux-mm, linux-nfs, linux-um, linux-unionfs, linux-xfs, lkml, ntfs3, nvdimm, ocfs2-devel, v9fs
Subsystem:
coda file system, ecrypt file system, exec & binfmt api, elf, filesystems (vfs and infrastructure), filesystems [stackable], the rest · Maintainers:
Jan Harkes, Tyler Hicks, Kees Cook, Alexander Viro, Christian Brauner, Miklos Szeredi, Amir Goldstein, Linus Torvalds
Since commit c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file
callback"), the f_op->mmap() hook has been deprecated in favour of
f_op->mmap_prepare().
Additionally, commit bb666b7c2707 ("mm: add mmap_prepare() compatibility
layer for nested file systems") permits the use of the .mmap_prepare() hook
even in nested filesystems like overlayfs.
There are a number of places where we check only for f_op->mmap - this is
incorrect now mmap_prepare exists, so update all of these to use the
general helper file_has_valid_mmap_hooks().
Most notably, this updates the elf logic to allow for the ability to
execute binaries on filesystems which have the .mmap_prepare hook, but
additionally we update nested filesystems.
Signed-off-by: Lorenzo Stoakes <redacted>
---
fs/backing-file.c | 2 +-
fs/binfmt_elf.c | 4 ++--
fs/binfmt_elf_fdpic.c | 2 +-
fs/coda/file.c | 2 +-
fs/ecryptfs/file.c | 2 +-
5 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/fs/backing-file.c b/fs/backing-file.c
index 04018679bf69..5761db9a52a9 100644
--- a/fs/backing-file.c
+++ b/fs/backing-file.c@@ -333,7 +333,7 @@ int backing_file_mmap(struct file *file, struct vm_area_struct *vma, if (WARN_ON_ONCE(!(file->f_mode & FMODE_BACKING))) return -EIO; - if (!file->f_op->mmap) + if (!file_has_valid_mmap_hooks(file)) return -ENODEV; vma_set_file(vma, file);
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index a43363d593e5..a6750bd9392a 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c@@ -646,7 +646,7 @@ static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex, if (!elf_check_arch(interp_elf_ex) || elf_check_fdpic(interp_elf_ex)) goto out; - if (!interpreter->f_op->mmap) + if (!file_has_valid_mmap_hooks(interpreter)) goto out; total_size = total_mapping_size(interp_elf_phdata,
@@ -848,7 +848,7 @@ static int load_elf_binary(struct linux_binprm *bprm) goto out; if (elf_check_fdpic(elf_ex)) goto out; - if (!bprm->file->f_op->mmap) + if (!file_has_valid_mmap_hooks(bprm->file)) goto out; elf_phdata = load_elf_phdrs(elf_ex, bprm->file);
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 9133f3827f90..699bb9a65c27 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c@@ -109,7 +109,7 @@ static int is_elf(struct elfhdr *hdr, struct file *file) return 0; if (!elf_check_arch(hdr)) return 0; - if (!file->f_op->mmap) + if (!file_has_valid_mmap_hooks(file)) return 0; return 1; }
diff --git a/fs/coda/file.c b/fs/coda/file.c
index 2e6ea9319b35..eed45a80e9bc 100644
--- a/fs/coda/file.c
+++ b/fs/coda/file.c@@ -160,7 +160,7 @@ coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma) size_t count; int ret; - if (!host_file->f_op->mmap) + if (!file_has_valid_mmap_hooks(host_file)) return -ENODEV; if (WARN_ON(coda_file != vma->vm_file))
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index ce0a3c5ed0ca..2bd50d1de5ef 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c@@ -193,7 +193,7 @@ static int ecryptfs_mmap(struct file *file, struct vm_area_struct *vma) * natively. If FILESYSTEM_MAX_STACK_DEPTH > 2 or ecryptfs * allows recursive mounting, this will need to be extended. */ - if (!lower_file->f_op->mmap) + if (!file_has_valid_mmap_hooks(lower_file)) return -ENODEV; return generic_file_mmap(file, vma); }
--
2.49.0