On Fri, Jul 19, 2019 at 08:43:29PM +0800, Yin Fengwei wrote: > syzbot reported general protection fault in kstrtouint: > https://lkml.org/lkml/2019/7/18/328 > > >From the log, if the mount option is something like: > fd,XXXXXXXXXXXXXXXXXXXX > > The default parameter (which has NULL param->string) will be > passed to vfs_parse_fs_param. Finally, this NULL param->string > is passed to kstrtouint and trigger NULL pointer access. > > Reported-by: syzbot+398343b7c1b1b989228d@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: 71cbb7570a9a ("vfs: Move the subtype parameter into fuse") > > Signed-off-by: Yin Fengwei <nh26223.lmm@xxxxxxxxx> > --- > fs/fs_parser.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/fs/fs_parser.c b/fs/fs_parser.c > index d13fe7d797c2..578e6880ac67 100644 > --- a/fs/fs_parser.c > +++ b/fs/fs_parser.c > @@ -210,6 +210,10 @@ int fs_parse(struct fs_context *fc, > case fs_param_is_fd: { > switch (param->type) { > case fs_value_is_string: > + if (result->has_value) { > + goto bad_value; > + } Always run checkpatch.pl so grumpy maintainers do not tell you to go run checkpatch.pl :)
