[v4,04/11] bpftool: Ensure task comm is always NUL-terminated

Commit Message

Yafang Shao July 29, 2024, 2:37 a.m. UTC

Let's explicitly ensure the destination string is NUL-terminated. This way,
it won't be affected by changes to the source string.

Signed-off-by: Yafang Shao <[e-mail]>
Reviewed-by: Quentin Monnet <[e-mail]>
---
 tools/bpf/bpftool/pids.c | 2 ++
 1 file changed, 2 insertions(+)

Patch

diff --git a/tools/bpf/bpftool/pids.c b/tools/bpf/bpftool/pids.c
index 9b898571b49e..23f488cf1740 100644
--- a/tools/bpf/bpftool/pids.c
+++ b/tools/bpf/bpftool/pids.c
@@ -54,6 +54,7 @@  static void add_ref(struct hashmap *map, struct pid_iter_entry *e)
 		ref = &refs->refs[refs->ref_cnt];
 		ref->pid = e->pid;
 		memcpy(ref->comm, e->comm, sizeof(ref->comm));
+		ref->comm[sizeof(ref->comm) - 1] = '\0';
 		refs->ref_cnt++;
 
 		return;
@@ -77,6 +78,7 @@  static void add_ref(struct hashmap *map, struct pid_iter_entry *e)
 	ref = &refs->refs[0];
 	ref->pid = e->pid;
 	memcpy(ref->comm, e->comm, sizeof(ref->comm));
+	ref->comm[sizeof(ref->comm) - 1] = '\0';
 	refs->ref_cnt = 1;
 	refs->has_bpf_cookie = e->has_bpf_cookie;
 	refs->bpf_cookie = e->bpf_cookie;