cifs: make cifs_ioctl handle NULL filp->private_data correctly
Commit 13cfb7334e made cifs_ioctl use the tlink attached to the
cifsFileInfo for a filp. This ignores the case of an open directory
however, which in CIFS can have a NULL private_data until a readdir
is done on it.
This patch re-adds the NULL pointer checks that were removed in commit
50ae28f01 and moves the setting of tcon and "caps" variables lower.
Long term, a better fix would be to establish a f_op->open routine for
directories that populates that field at open time, but that requires
some other changes to how readdir calls are handled.
Reported-by: Kjell Rune Skaaraas <kjella79@yahoo.no>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
index 2fa22f2..0c98672 100644
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -38,10 +38,10 @@
struct cifs_sb_info *cifs_sb;
#ifdef CONFIG_CIFS_POSIX
struct cifsFileInfo *pSMBFile = filep->private_data;
- struct cifsTconInfo *tcon = tlink_tcon(pSMBFile->tlink);
+ struct cifsTconInfo *tcon;
__u64 ExtAttrBits = 0;
__u64 ExtAttrMask = 0;
- __u64 caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
+ __u64 caps;
#endif /* CONFIG_CIFS_POSIX */
xid = GetXid();
@@ -62,6 +62,10 @@
break;
#ifdef CONFIG_CIFS_POSIX
case FS_IOC_GETFLAGS:
+ if (pSMBFile == NULL)
+ break;
+ tcon = tlink_tcon(pSMBFile->tlink);
+ caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
if (CIFS_UNIX_EXTATTR_CAP & caps) {
rc = CIFSGetExtAttr(xid, tcon, pSMBFile->netfid,
&ExtAttrBits, &ExtAttrMask);
@@ -73,6 +77,10 @@
break;
case FS_IOC_SETFLAGS:
+ if (pSMBFile == NULL)
+ break;
+ tcon = tlink_tcon(pSMBFile->tlink);
+ caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
if (CIFS_UNIX_EXTATTR_CAP & caps) {
if (get_user(ExtAttrBits, (int __user *)arg)) {
rc = -EFAULT;