diff options
| author | Peilin Ye <yepeilin.cs@gmail.com> | 2020-07-14 14:09:04 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-11 15:35:34 +0200 |
| commit | 06b46481d51fac58bb776067478ceeb460339a57 (patch) | |
| tree | 2869199304af3fdf5245ea0e52bd26f30a94af25 /kernel | |
| parent | 5cca11ebb504fe17de1a111b07317789fdab5da7 (diff) | |
bpf: Fix NULL pointer dereference in __btf_resolve_helper_id()
[ Upstream commit 5b801dfb7feb2738975d80223efc2fc193e55573 ]
Prevent __btf_resolve_helper_id() from dereferencing `btf_vmlinux`
as NULL. This patch fixes the following syzbot bug:
https://syzkaller.appspot.com/bug?id=f823224ada908fa5c207902a5a62065e53ca0fcc
Reported-by: syzbot+ee09bda7017345f1fbe6@syzkaller.appspotmail.com
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200714180904.277512-1-yepeilin.cs@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/btf.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index d1f5d428c9fe..6cafc596631c 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -4011,6 +4011,11 @@ static int __btf_resolve_helper_id(struct bpf_verifier_log *log, void *fn, const char *tname, *sym; u32 btf_id, i; + if (!btf_vmlinux) { + bpf_log(log, "btf_vmlinux doesn't exist\n"); + return -EINVAL; + } + if (IS_ERR(btf_vmlinux)) { bpf_log(log, "btf_vmlinux is malformed\n"); return -EINVAL; |