[PATCH bpf-next] bpf: ensure all memory is initialized in bpf_get_current_comm

Barret Rhoden
2023-04-07T00:18:30Z

BPF helpers that take an ARG_PTR_TO_UNINIT_MEM must ensure that all of
the memory is set, including beyond the end of the string.

Signed-off-by: Barret Rhoden <brho@google.com>
---
kernel/bpf/helpers.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 6be16db9f188..b6a5cda5bb59 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -258,7 +258,7 @@ BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size)
goto err_clear;

/* Verifier guarantees that size > 0 */
- strscpy(buf, task->comm, size);
+ strscpy_pad(buf, task->comm, size);
return 0;
err_clear:
memset(buf, 0, size);
--
2.40.0.577.gac1e443424-goog