summaryrefslogtreecommitdiffstats
path: root/fs/f2fs
diff options
context:
space:
mode:
authorChao Yu <yuchao0@huawei.com>2020-12-26 18:07:01 +0800
committerJaegeuk Kim <jaegeuk@kernel.org>2021-01-27 15:20:01 -0800
commite0fcd01510ad025c9bbce704c5c2579294056141 (patch)
tree2e8600f858c216e4dae80d4617a0ce2d4504a2af /fs/f2fs
parent17232e830afb800acdcc22ae8980bf9d330393ef (diff)
downloadlinux-stable-e0fcd01510ad025c9bbce704c5c2579294056141.tar.gz
linux-stable-e0fcd01510ad025c9bbce704c5c2579294056141.tar.bz2
linux-stable-e0fcd01510ad025c9bbce704c5c2579294056141.zip
f2fs: enforce the immutable flag on open files
This patch ports commit 02b016ca7f99 ("ext4: enforce the immutable flag on open files") to f2fs. According to the chattr man page, "a file with the 'i' attribute cannot be modified..." Historically, this was only enforced when the file was opened, per the rest of the description, "... and the file can not be opened in write mode". There is general agreement that we should standardize all file systems to prevent modifications even for files that were opened at the time the immutable flag is set. Eventually, a change to enforce this at the VFS layer should be landing in mainline. Cc: stable@kernel.org Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs')
-rw-r--r--fs/f2fs/file.c17
1 files changed, 17 insertions, 0 deletions
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 2ddc4baaf173..d57b54643918 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -60,6 +60,9 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault *vmf)
bool need_alloc = true;
int err = 0;
+ if (unlikely(IS_IMMUTABLE(inode)))
+ return VM_FAULT_SIGBUS;
+
if (unlikely(f2fs_cp_error(sbi))) {
err = -EIO;
goto err;
@@ -865,6 +868,14 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
return -EIO;
+ if (unlikely(IS_IMMUTABLE(inode)))
+ return -EPERM;
+
+ if (unlikely(IS_APPEND(inode) &&
+ (attr->ia_valid & (ATTR_MODE | ATTR_UID |
+ ATTR_GID | ATTR_TIMES_SET))))
+ return -EPERM;
+
if ((attr->ia_valid & ATTR_SIZE) &&
!f2fs_is_compress_backend_ready(inode))
return -EOPNOTSUPP;
@@ -4351,6 +4362,11 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
inode_lock(inode);
}
+ if (unlikely(IS_IMMUTABLE(inode))) {
+ ret = -EPERM;
+ goto unlock;
+ }
+
ret = generic_write_checks(iocb, from);
if (ret > 0) {
bool preallocated = false;
@@ -4415,6 +4431,7 @@ write:
if (ret > 0)
f2fs_update_iostat(F2FS_I_SB(inode), APP_WRITE_IO, ret);
}
+unlock:
inode_unlock(inode);
out:
trace_f2fs_file_write_iter(inode, iocb->ki_pos,