lkml.org 
[lkml]   [2020]   [Aug]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Linux-kernel-mentees] [PATCH] hfs, hfsplus: Fix NULL pointer dereference in hfs_find_init()
On Wed, Aug 12, 2020 at 09:08:27AM +0200, Greg Kroah-Hartman wrote:
> On Wed, Aug 12, 2020 at 02:55:56AM -0400, Peilin Ye wrote:
> > Prevent hfs_find_init() from dereferencing `tree` as NULL.
> >
> > Reported-and-tested-by: syzbot+7ca256d0da4af073b2e2@syzkaller.appspotmail.com
> > Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
> > ---
> > fs/hfs/bfind.c | 3 +++
> > fs/hfsplus/bfind.c | 3 +++
> > 2 files changed, 6 insertions(+)
> >
> > diff --git a/fs/hfs/bfind.c b/fs/hfs/bfind.c
> > index 4af318fbda77..880b7ea2c0fc 100644
> > --- a/fs/hfs/bfind.c
> > +++ b/fs/hfs/bfind.c
> > @@ -16,6 +16,9 @@ int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd)
> > {
> > void *ptr;
> >
> > + if (!tree)
> > + return -EINVAL;
> > +
> > fd->tree = tree;
> > fd->bnode = NULL;
> > ptr = kmalloc(tree->max_key_len * 2 + 4, GFP_KERNEL);
> > diff --git a/fs/hfsplus/bfind.c b/fs/hfsplus/bfind.c
> > index ca2ba8c9f82e..85bef3e44d7a 100644
> > --- a/fs/hfsplus/bfind.c
> > +++ b/fs/hfsplus/bfind.c
> > @@ -16,6 +16,9 @@ int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd)
> > {
> > void *ptr;
> >
> > + if (!tree)
> > + return -EINVAL;
> > +
>
> How can tree ever be NULL in these calls? Shouldn't that be fixed as
> the root problem here?

I see, I will try to figure out what is going on with the reproducer.

Thank you,
Peilin Ye

\
 
 \ /
  Last update: 2020-08-12 09:13    [W:0.060 / U:0.788 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site