[PATCH] Infiniband: Fix potential NULL d_inode dereference
From: David Howells
Date: Tue Jan 27 2015 - 10:01:35 EST
Code that does this:
if (!(d_unhashed(tmp) && tmp->d_inode)) {
...
simple_unlink(parent->d_inode, tmp);
}
is broken because:
!(d_unhashed(tmp) && tmp->d_inode)
is equivalent to:
!d_unhashed(tmp) || !tmp->d_inode
so it is possible to get into simple_unlink() with tmp->d_inode == NULL.
simple_unlink(), however, assumes tmp->d_inode cannot be NULL.
I think that what was meant is this:
!d_unhashed(tmp) && tmp->d_inode
and that the logical-not operator or the final close-bracket was misplaced.
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Bryan O'Sullivan <bos@xxxxxxxxxxxxx>
cc: Roland Dreier <rolandd@xxxxxxxxx>
---
drivers/infiniband/hw/ipath/ipath_fs.c | 2 +-
drivers/infiniband/hw/qib/qib_fs.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/infiniband/hw/ipath/ipath_fs.c b/drivers/infiniband/hw/ipath/ipath_fs.c
index 4977082e081f..33c45dfcbd88 100644
--- a/drivers/infiniband/hw/ipath/ipath_fs.c
+++ b/drivers/infiniband/hw/ipath/ipath_fs.c
@@ -277,7 +277,7 @@ static int remove_file(struct dentry *parent, char *name)
}
spin_lock(&tmp->d_lock);
- if (!(d_unhashed(tmp) && tmp->d_inode)) {
+ if (!d_unhashed(tmp) && tmp->d_inode) {
dget_dlock(tmp);
__d_drop(tmp);
spin_unlock(&tmp->d_lock);
diff --git a/drivers/infiniband/hw/qib/qib_fs.c b/drivers/infiniband/hw/qib/qib_fs.c
index 81854586c081..d2427640d7e9 100644
--- a/drivers/infiniband/hw/qib/qib_fs.c
+++ b/drivers/infiniband/hw/qib/qib_fs.c
@@ -455,7 +455,7 @@ static int remove_file(struct dentry *parent, char *name)
}
spin_lock(&tmp->d_lock);
- if (!(d_unhashed(tmp) && tmp->d_inode)) {
+ if (!d_unhashed(tmp) && tmp->d_inode) {
__d_drop(tmp);
spin_unlock(&tmp->d_lock);
simple_unlink(parent->d_inode, tmp);
--
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