From: Maciej Żenczykowski maze@google.com
[ Upstream commit 2c16db6c92b0ee4aa61e88366df82169e83c3f7e ]
Android userspace has been using TCA_KIND with a char[IFNAMESIZ] many-null-terminated buffer containing the string 'bpf'.
This works on 4.19 and ceases to work on 5.10.
I'm not entirely sure what fixes tag to use, but I think the issue was likely introduced in the below mentioned 5.4 commit.
Reported-by: Nucca Chen nuccachen@google.com Cc: Cong Wang xiyou.wangcong@gmail.com Cc: David Ahern dsahern@gmail.com Cc: David S. Miller davem@davemloft.net Cc: Jakub Kicinski jakub.kicinski@netronome.com Cc: Jamal Hadi Salim jhs@mojatatu.com Cc: Jiri Pirko jiri@mellanox.com Cc: Jiri Pirko jiri@resnulli.us Fixes: 62794fc4fbf5 ("net_sched: add max len check for TCA_KIND") Change-Id: I66dc281f165a2858fc29a44869a270a2d698a82b Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- lib/nlattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/nlattr.c b/lib/nlattr.c index e335bcafa9e4..00bfc6aece05 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -402,7 +402,7 @@ int nla_strcmp(const struct nlattr *nla, const char *str) int attrlen = nla_len(nla); int d;
- if (attrlen > 0 && buf[attrlen - 1] == '\0') + while (attrlen > 0 && buf[attrlen - 1] == '\0') attrlen--;
d = attrlen - len;