Hello. I tried to insert a new LSM hook for truncate operation, but I had to insert security_path_truncate() hook into multiple locations since do_truncate() is directly called from some locations. http://svn.sourceforge.jp/cgi-bin/viewcvs.cgi/*checkout*/trunk/2.2.x/tomoyo-lsm/patches/lsm-add-hooks-for-pathname-based-control.patch?rev=1244&root=tomoyo Is it possible to replace do_truncate() and file_truncate() with path_truncate() so that security_path_truncate() is called from only path_truncate()? Regards. ---------- Subject: Replace do_truncate() and file_truncate() with path_truncate(). This patch replaces do_truncate() and file_truncate() with path_truncate(). Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> --- fs/exec.c | 2 +- fs/namei.c | 14 +++++++------- fs/open.c | 21 ++++++++++++--------- include/linux/fs.h | 6 ++---- mm/tiny-shmem.c | 2 +- 5 files changed, 23 insertions(+), 22 deletions(-) --- vfs.orig/fs/exec.c +++ vfs/fs/exec.c @@ -1763,7 +1763,7 @@ int do_coredump(long signr, int exit_cod goto close_fail; if (!file->f_op->write) goto close_fail; - if (!ispipe && file_truncate(file, 0, 0) != 0) + if (!ispipe && path_truncate(&file->f_path, 0, 0, file) != 0) goto close_fail; retval = binfmt->core_dump(signr, regs, file, core_limit); --- vfs.orig/fs/namei.c +++ vfs/fs/namei.c @@ -1626,8 +1626,8 @@ EXPORT_SYMBOL(path_create); int may_open(struct nameidata *nd, int acc_mode, int flag) { int op; - struct dentry *dentry = nd->path.dentry; - struct inode *inode = dentry->d_inode; + struct path *path = &nd->path; + struct inode *inode = path->dentry->d_inode; int error; if (!inode) @@ -1647,14 +1647,14 @@ int may_open(struct nameidata *nd, int a if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { flag &= ~O_TRUNC; } else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) { - if (nd->path.mnt->mnt_flags & MNT_NODEV) + if (path->mnt->mnt_flags & MNT_NODEV) return -EACCES; flag &= ~O_TRUNC; } op = (nd->flags & LOOKUP_OPEN) ? PERM_OP_OPEN : 0; - error = path_permission(&nd->path, acc_mode | op); + error = path_permission(path, acc_mode | op); if (error) return error; /* @@ -1691,9 +1691,9 @@ int may_open(struct nameidata *nd, int a if (!error) { DQUOT_INIT(inode); - error = do_truncate(dentry, 0, - ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, - NULL); + error = path_truncate(path, 0, + ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, + NULL); } put_write_access(inode); if (error) --- vfs.orig/fs/open.c +++ vfs/fs/open.c @@ -200,10 +200,10 @@ out: * @dentry: the dentry to truncate * @length: the new length * @time_attrs: file times to be updated (e.g. ATTR_MTIME|ATTR_CTIME) - * @filp: an open file or NULL (see file_truncate() as well) + * @filp: an open file or NULL */ -int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, - struct file *filp) +static inline int do_truncate(struct dentry *dentry, loff_t length, + unsigned int time_attrs, struct file *filp) { int err; struct iattr newattrs; @@ -229,14 +229,16 @@ int do_truncate(struct dentry *dentry, l } /* - * file_truncate - truncate (or extend) an open file - * @filp: the open file + * path_truncate - truncate (or extend) a file + * @path: the path structure to truncate * @length: the new length * @time_attrs: file times to be updated (e.g. ATTR_MTIME|ATTR_CTIME) + * @filp: an open file or NULL */ -int file_truncate(struct file *filp, loff_t length, unsigned int time_attrs) +int path_truncate(struct path *path, loff_t length, unsigned int time_attrs, + struct file *filp) { - return do_truncate(filp->f_path.dentry, length, time_attrs, filp); + return do_truncate(path->dentry, length, time_attrs, filp); } static long do_sys_truncate(const char __user * path, loff_t length) @@ -290,7 +292,7 @@ static long do_sys_truncate(const char _ error = locks_verify_truncate(inode, NULL, length); if (!error) { DQUOT_INIT(inode); - error = do_truncate(nd.path.dentry, length, 0, NULL); + error = path_truncate(&nd.path, length, 0, NULL); } put_write_and_out: @@ -343,7 +345,8 @@ static long do_sys_ftruncate(unsigned in error = locks_verify_truncate(inode, file, length); if (!error) - error = file_truncate(file, length, ATTR_MTIME|ATTR_CTIME); + error = path_truncate(&file->f_path, length, + ATTR_MTIME|ATTR_CTIME, file); out_putf: fput(file); out: --- vfs.orig/include/linux/fs.h +++ vfs/include/linux/fs.h @@ -1609,10 +1609,8 @@ static inline int break_lease(struct ino /* fs/open.c */ -extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs, - struct file *filp); -extern int file_truncate(struct file *filp, loff_t start, - unsigned int time_attrs); +extern int path_truncate(struct path *path, loff_t start, + unsigned int time_attrs, struct file *filp); extern long do_sys_open(int dfd, const char __user *filename, int flags, int mode); extern struct file *filp_open(const char *, int, int); --- vfs.orig/mm/tiny-shmem.c +++ vfs/mm/tiny-shmem.c @@ -80,7 +80,7 @@ struct file *shmem_file_setup(char *name inode->i_nlink = 0; /* It is unlinked */ /* notify everyone as to the change of file size */ - error = file_truncate(file, size, 0); + error = path_truncate(&file->f_path, size, 0, file); if (error < 0) goto close_file; -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
