From: Andrii Nakryiko <andrii@kernel.org>
Date: Wed, 29 May 2024 23:12:12 +0000 (-0700)
Subject: libbpf: don't close(-1) in multi-uprobe feature detector
X-Git-Tag: v6.10-rc3~27^2~6^2~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7d0b3953f6d832daec10a0d76e2d4db405768a8b;p=thirdparty%2Fkernel%2Flinux.git

libbpf: don't close(-1) in multi-uprobe feature detector

Guard close(link_fd) with extra link_fd >= 0 check to prevent close(-1).

Detected by Coverity static analysis.

Fixes: 04d939a2ab22 ("libbpf: detect broken PID filtering logic for multi-uprobe")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20240529231212.768828-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---

diff --git a/tools/lib/bpf/features.c b/tools/lib/bpf/features.c
index 3df0125ed5fa7..50befe125ddc5 100644
--- a/tools/lib/bpf/features.c
+++ b/tools/lib/bpf/features.c
@@ -393,7 +393,8 @@ static int probe_uprobe_multi_link(int token_fd)
 	err = -errno; /* close() can clobber errno */
 
 	if (link_fd >= 0 || err != -EBADF) {
-		close(link_fd);
+		if (link_fd >= 0)
+			close(link_fd);
 		close(prog_fd);
 		return 0;
 	}