From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit b41d936b5ecfdb3a4abc525ce6402a6c49cffddc ]
syzbot managed to crash the kernel in tabledist() loading
an empty distribution table.
t = dist->table[rnd % dist->size];
Simply return an error when such load is attempted.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/sched/sch_netem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index b17f2ed970e29..f5cb35e550f8d 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -777,7 +777,7 @@ static int get_dist_table(struct Qdisc *sch, struct disttable **tbl,
struct disttable *d;
int i;
- if (n > NETEM_DIST_MAX)
+ if (!n || n > NETEM_DIST_MAX)
return -EINVAL;
d = kvmalloc(sizeof(struct disttable) + n * sizeof(s16), GFP_KERNEL);
--
2.20.1
