Commit 09d49eb9 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Andrew Morton
Browse files

ocfs2: reduce ioctl stack usage 

On 32-bit architectures with KASAN_STACK enabled, the total stack usage of
the ocfs2_ioctl function grows beyond the warning limit:

fs/ocfs2/ioctl.c: In function 'ocfs2_ioctl':
fs/ocfs2/ioctl.c:934:1: error: the frame size of 1448 bytes is larger than 1400 bytes [-Werror=frame-larger-than=]

Move each of the variables into a basic block, and mark
ocfs2_info_handle() as noinline_for_stack, in order to have the variable
share stack slots.

Link: https://lkml.kernel.org/r/20230417205631.1956027-1-arnd@kernel.org


Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Reviewed-by: default avatarJoseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: default avatarMark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 522dc4e5

fs/ocfs2/ioctl.c

+26 −11
Original line number Diff line number Diff line
@@ -803,8 +803,8 @@ static int ocfs2_get_request_ptr(struct ocfs2_info *info, int idx, 
 * a better backward&forward compatibility, since a small piece of

 * request will be less likely to be broken if disk layout get changed.

 */

static int ocfs2_info_handle(struct inode *inode, struct ocfs2_info *info,

			     int compat_flag)

static noinline_for_stack int

ocfs2_info_handle(struct inode *inode, struct ocfs2_info *info, int compat_flag)

{

	int i, status = 0;

	u64 req_addr;
@@ -840,27 +840,26 @@ static int ocfs2_info_handle(struct inode *inode, struct ocfs2_info *info, 
long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)

{

	struct inode *inode = file_inode(filp);

	int new_clusters;

	int status;

	struct ocfs2_space_resv sr;

	struct ocfs2_new_group_input input;

	struct reflink_arguments args;

	const char __user *old_path;

	const char __user *new_path;

	bool preserve;

	struct ocfs2_info info;

	void __user *argp = (void __user *)arg;

	int status;



	switch (cmd) {

	case OCFS2_IOC_RESVSP:

	case OCFS2_IOC_RESVSP64:

	case OCFS2_IOC_UNRESVSP:

	case OCFS2_IOC_UNRESVSP64:

	{

		struct ocfs2_space_resv sr;



		if (copy_from_user(&sr, (int __user *) arg, sizeof(sr)))

			return -EFAULT;



		return ocfs2_change_file_space(filp, cmd, &sr);

	}

	case OCFS2_IOC_GROUP_EXTEND:

	{

		int new_clusters;



		if (!capable(CAP_SYS_RESOURCE))

			return -EPERM;
@@ -873,8 +872,12 @@ long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 
		status = ocfs2_group_extend(inode, new_clusters);

		mnt_drop_write_file(filp);

		return status;

	}

	case OCFS2_IOC_GROUP_ADD:

	case OCFS2_IOC_GROUP_ADD64:

	{

		struct ocfs2_new_group_input input;



		if (!capable(CAP_SYS_RESOURCE))

			return -EPERM;
@@ -887,7 +890,14 @@ long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 
		status = ocfs2_group_add(inode, &input);

		mnt_drop_write_file(filp);

		return status;

	}

	case OCFS2_IOC_REFLINK:

	{

		struct reflink_arguments args;

		const char __user *old_path;

		const char __user *new_path;

		bool preserve;



		if (copy_from_user(&args, argp, sizeof(args)))

			return -EFAULT;

		old_path = (const char __user *)(unsigned long)args.old_path;
@@ -895,11 +905,16 @@ long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 
		preserve = (args.preserve != 0);



		return ocfs2_reflink_ioctl(inode, old_path, new_path, preserve);

	}

	case OCFS2_IOC_INFO:

	{

		struct ocfs2_info info;



		if (copy_from_user(&info, argp, sizeof(struct ocfs2_info)))

			return -EFAULT;



		return ocfs2_info_handle(inode, &info, 0);

	}

	case FITRIM:

	{

		struct super_block *sb = inode->i_sb;