From 618763958b2291a09057dbfa553da6ded93dcfad Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Mon, 8 Nov 2010 07:28:32 -0500 Subject: 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 Reviewed-and-Tested-by: Suresh Jayaraman Signed-off-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/ioctl.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) 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 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg) 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 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg) 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 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg) 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; -- cgit v1.1