From: Quentin Monnet <quentin.monnet@netronome.com>
Date: Thu, 8 Nov 2018 11:52:25 +0000
Subject: tools: bpftool: prevent infinite loop in get_fdinfo()
Patch-mainline: v4.20-rc5
Git-commit: 53909030aa29bffe1f8490df62176c2375135652
References: bsc#1109837
Function getline() returns -1 on failure to read a line, thus creating
an infinite loop in get_fdinfo() if the key is not found. Fix it by
calling the function only as long as we get a strictly positive return
value.
Found by copying the code for a key which is not always present...
Fixes: 71bb428fe2c1 ("tools: bpf: add bpftool")
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
tools/bpf/bpftool/common.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/bpf/bpftool/common.c
+++ b/tools/bpf/bpftool/common.c
@@ -304,7 +304,7 @@ char *get_fdinfo(int fd, const char *key
return NULL;
}
- while ((n = getline(&line, &line_n, fdi))) {
+ while ((n = getline(&line, &line_n, fdi)) > 0) {
char *value;
int len;