From 28d36e3702fcbed73c38e877bcf2a8f8946b7f3d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 14 Jan 2008 23:09:56 -0800 Subject: [PATCH] [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 Signed-off-by: David S. Miller --- net/ipv4/fib_trie.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index 18fb73958a4..72c78c2209d 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -2284,10 +2284,8 @@ static void seq_indent(struct seq_file *seq, int n) 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 @@ static inline const char *rtn_scope(enum rt_scope_t s) 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 @@ static const char *rtn_type_names[__RTN_MAX] = { [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 @@ static int fib_trie_seq_show(struct seq_file *seq, void *v) 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); -- 2.41.0