[FIB]: Avoid using static variables without proper locking
fib_trie_seq_show() uses two helper functions, rtn_scope() and
rtn_type() that can write to static storage without locking.
Just pass to them a temporary buffer to avoid potential corruption
(probably not triggerable but still...)
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 18fb739..72c78c2 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -2284,10 +2284,8 @@
while (n-- > 0) seq_puts(seq, " ");
}
-static inline const char *rtn_scope(enum rt_scope_t s)
+static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s)
{
- static char buf[32];
-
switch (s) {
case RT_SCOPE_UNIVERSE: return "universe";
case RT_SCOPE_SITE: return "site";
@@ -2295,7 +2293,7 @@
case RT_SCOPE_HOST: return "host";
case RT_SCOPE_NOWHERE: return "nowhere";
default:
- snprintf(buf, sizeof(buf), "scope=%d", s);
+ snprintf(buf, len, "scope=%d", s);
return buf;
}
}
@@ -2315,13 +2313,11 @@
[RTN_XRESOLVE] = "XRESOLVE",
};
-static inline const char *rtn_type(unsigned t)
+static inline const char *rtn_type(char *buf, size_t len, unsigned t)
{
- static char buf[32];
-
if (t < __RTN_MAX && rtn_type_names[t])
return rtn_type_names[t];
- snprintf(buf, sizeof(buf), "type %u", t);
+ snprintf(buf, len, "type %u", t);
return buf;
}
@@ -2359,13 +2355,19 @@
seq_printf(seq, " |-- %d.%d.%d.%d\n", NIPQUAD(val));
for (i = 32; i >= 0; i--) {
struct leaf_info *li = find_leaf_info(l, i);
+
if (li) {
struct fib_alias *fa;
+
list_for_each_entry_rcu(fa, &li->falh, fa_list) {
+ char buf1[32], buf2[32];
+
seq_indent(seq, iter->depth+1);
seq_printf(seq, " /%d %s %s", i,
- rtn_scope(fa->fa_scope),
- rtn_type(fa->fa_type));
+ rtn_scope(buf1, sizeof(buf1),
+ fa->fa_scope),
+ rtn_type(buf2, sizeof(buf2),
+ fa->fa_type));
if (fa->fa_tos)
seq_printf(seq, "tos =%d\n",
fa->fa_tos);