[PATCH v3 bpf-next 08/19] bpf: fix missing -EFAULT return on user log buf error in btf_parse()

[Andrii Nakryiko <andrii@xxxxxxxxxx>]

btf_parse() is missing -EFAULT error return if log->ubuf was NULL-ed out
due to error while copying data into user-provided buffer. Add it, but
handle a special case of BPF_LOG_KERNEL in which log->ubuf is always NULL.

Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
---
 kernel/bpf/btf.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 2574cc9b3e28..a67b1b669b0c 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -5598,6 +5598,10 @@ static struct btf *btf_parse(bpfptr_t btf_data, u32 btf_data_size,
 		err = -ENOSPC;
 		goto errout_meta;
 	}
+	if (log->level && log->level != BPF_LOG_KERNEL && !log->ubuf) {
+		err = -EFAULT;
+		goto errout_meta;
+	}
 
 	btf_verifier_env_free(env);
 	refcount_set(&btf->refcnt, 1);
-- 
2.34.1