Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f0494206 authored by Yan, Zheng's avatar Yan, Zheng
Browse files

ceph: fix ceph_dir_llseek() 



Comparing offset with inode->i_sb->s_maxbytes doesn't make sense for
directory. For a fragmented directory, offset (frag_t, off) can be
larger than inode->i_sb->s_maxbytes.

At the very beginning of ceph_dir_llseek(), local variable old_offset
is initialized to parameter offset. This doesn't make sense neither.
Old_offset should be ceph_make_fpos(fi->frag, fi->next_offset).

Signed-off-by: default avatarYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: default avatarAlex Elder <elder@linaro.org>
parent 0ccd5926

fs/ceph/dir.c

+6 −6
Original line number Diff line number Diff line
@@ -190,7 +190,7 @@ static int __dcache_readdir(struct file *file, struct dir_context *ctx) 
		if (last) {

			/* remember our position */

			fi->dentry = last;

			fi->next_offset = di->offset;

			fi->next_offset = fpos_off(di->offset);

		}

		dput(dentry);

		return 0;
@@ -369,9 +369,9 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx) 
				fi->next_offset = 0;

			off = fi->next_offset;

		}

		fi->frag = frag;

		fi->offset = fi->next_offset;

		fi->last_readdir = req;

		fi->frag = frag;



		if (req->r_reply_info.dir_end) {

			kfree(fi->last_name);
@@ -474,7 +474,7 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence) 
{

	struct ceph_file_info *fi = file->private_data;

	struct inode *inode = file->f_mapping->host;

	loff_t old_offset = offset;

	loff_t old_offset = ceph_make_fpos(fi->frag, fi->next_offset);

	loff_t retval;



	mutex_lock(&inode->i_mutex);
@@ -491,7 +491,7 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence) 
		goto out;

	}



	if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) {

	if (offset >= 0) {

		if (offset != file->f_pos) {

			file->f_pos = offset;

			file->f_version = 0;
@@ -504,14 +504,14 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence) 
		 * seek to new frag, or seek prior to current chunk.

		 */

		if (offset == 0 ||

		    fpos_frag(offset) != fpos_frag(old_offset) ||

		    fpos_frag(offset) != fi->frag ||

		    fpos_off(offset) < fi->offset) {

			dout("dir_llseek dropping %p content\n", file);

			reset_readdir(fi);

		}



		/* bump dir_release_count if we did a forward seek */

		if (offset > old_offset)

		if (fpos_cmp(offset, old_offset) > 0)

			fi->dir_release_count--;

	}

out:

fs/ceph/super.h

+1 −1
Original line number Diff line number Diff line
@@ -577,7 +577,7 @@ struct ceph_file_info { 


	/* readdir: position within a frag */

	unsigned offset;       /* offset of last chunk, adjusted for . and .. */

	u64 next_offset;       /* offset of next chunk (last_name's + 1) */

	unsigned next_offset;  /* offset of next chunk (last_name's + 1) */

	char *last_name;       /* last entry in previous chunk */

	struct dentry *dentry; /* next dentry (for dcache readdir) */

	int dir_release_count;