Merge "do_last(): fetch directory ->i_mode and ->i_uid before it's too late" (e8ebf257) · Commits · e / devices / android_kernel_sony_msm8998

fs/namei.c

+10 −7

Original line number	Diff line number	Diff line
		@@ -1087,7 +1087,8 @@ static int may_linkat(struct path *link)
		* may_create_in_sticky - Check whether an O_CREAT open in a sticky directory
		* should be allowed, or not, on files that already
		* exist.
		* @dir: the sticky parent directory
		* @dir_mode: mode bits of directory
		* @dir_uid: owner of directory
		* @inode: the inode of the file to open
		*
		* Block an O_CREAT open of a FIFO (or a regular file) when:
		@@ -1103,18 +1104,18 @@ static int may_linkat(struct path *link)
		*
		* Returns 0 if the open is allowed, -ve on error.
		*/
		static int may_create_in_sticky(struct dentry * const dir,
		static int may_create_in_sticky(umode_t dir_mode, kuid_t dir_uid,
		struct inode * const inode)
		{
		if ((!sysctl_protected_fifos && S_ISFIFO(inode->i_mode)) \|\|
		(!sysctl_protected_regular && S_ISREG(inode->i_mode)) \|\|
		likely(!(dir->d_inode->i_mode & S_ISVTX)) \|\|
		uid_eq(inode->i_uid, dir->d_inode->i_uid) \|\|
		likely(!(dir_mode & S_ISVTX)) \|\|
		uid_eq(inode->i_uid, dir_uid) \|\|
		uid_eq(current_fsuid(), inode->i_uid))
		return 0;

		if (likely(dir->d_inode->i_mode & 0002) \|\|
		(dir->d_inode->i_mode & 0020 &&
		if (likely(dir_mode & 0002) \|\|
		(dir_mode & 0020 &&
		((sysctl_protected_fifos >= 2 && S_ISFIFO(inode->i_mode)) \|\|
		(sysctl_protected_regular >= 2 && S_ISREG(inode->i_mode))))) {
		return -EACCES;
		@@ -3181,6 +3182,8 @@ static int do_last(struct nameidata *nd,
		int *opened)
		{
		struct dentry *dir = nd->path.dentry;
		kuid_t dir_uid = dir->d_inode->i_uid;
		umode_t dir_mode = dir->d_inode->i_mode;
		int open_flag = op->open_flag;
		bool will_truncate = (open_flag & O_TRUNC) != 0;
		bool got_write = false;
		@@ -3333,7 +3336,7 @@ finish_open:
		error = -EISDIR;
		if (d_is_dir(nd->path.dentry))
		goto out;
		error = may_create_in_sticky(dir,
		error = may_create_in_sticky(dir_mode, dir_uid,
		d_backing_inode(nd->path.dentry));
		if (unlikely(error))
		goto out;