Commit fc513fac authored by Ronnie Sahlberg's avatar Ronnie Sahlberg Committed by Steve French
Browse files

cifs: don't leak -EAGAIN for stat() during reconnect 



If from cifs_revalidate_dentry_attr() the SMB2/QUERY_INFO call fails with an
error, such as STATUS_SESSION_EXPIRED, causing the session to be reconnected
it is possible we will leak -EAGAIN back to the application even for
system calls such as stat() where this is not a valid error.

Fix this by re-trying the operation from within cifs_revalidate_dentry_attr()
if cifs_get_inode_info*() returns -EAGAIN.

This fixes stat() and possibly also other system calls that uses
cifs_revalidate_dentry*().

Signed-off-by: default avatarRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
Reviewed-by: default avatarPavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: default avatarAurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
parent f8788d86

fs/cifs/inode.c

+5 −1
Original line number Diff line number Diff line
@@ -2073,6 +2073,7 @@ int cifs_revalidate_dentry_attr(struct dentry *dentry) 
	struct inode *inode = d_inode(dentry);

	struct super_block *sb = dentry->d_sb;

	char *full_path = NULL;

	int count = 0;



	if (inode == NULL)

		return -ENOENT;
@@ -2094,15 +2095,18 @@ int cifs_revalidate_dentry_attr(struct dentry *dentry) 
		 full_path, inode, inode->i_count.counter,

		 dentry, cifs_get_time(dentry), jiffies);



again:

	if (cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext)

		rc = cifs_get_inode_info_unix(&inode, full_path, sb, xid);

	else

		rc = cifs_get_inode_info(&inode, full_path, NULL, sb,

					 xid, NULL);



	if (rc == -EAGAIN && count++ < 10)

		goto again;

out:

	kfree(full_path);

	free_xid(xid);



	return rc;

}