On Sun, Dec 15, 2019 at 09:44:32AM -0600, Aditya Pakki wrote: > If fp_old is NULL in bpf_prog_realloc, the program does an assertion > and crashes. However, we can continue execution by returning NULL to > the upper callers. The patch fixes this issue. > > Signed-off-by: Aditya Pakki <pakki001@xxxxxxx> > --- > kernel/bpf/core.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c > index 49e32acad7d8..4b46654fb26b 100644 > --- a/kernel/bpf/core.c > +++ b/kernel/bpf/core.c > @@ -222,7 +222,8 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, > u32 pages, delta; > int ret; > > - BUG_ON(fp_old == NULL); > + if (!fp_old) > + return NULL; This change makes no sense to me. fp_old should be valid. That's the point of BUG_ON. It can happen only during development. Can remove BUG_ON just as well and let kernel page fault.
