diff options
| author | Ignacy Gawędzki <ignacy.gawedzki@green-communications.fr> | 2015-02-14 01:47:05 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-02-19 23:45:53 +0300 |
| commit | 1c4cff0cf55011792125b6041bc4e9713e46240f (patch) | |
| tree | ecc9dc4e465d69c6e6afff06c6a473af7a6cc65a | |
| parent | 5c2770079fb9b8c5bfb7113d9e76de66e77a0e24 (diff) | |
| download | linux-1c4cff0cf55011792125b6041bc4e9713e46240f.tar.xz | |
gen_stats.c: Duplicate xstats buffer for later use
The gnet_stats_copy_app() function gets called, more often than not, with its
second argument a pointer to an automatic variable in the caller's stack.
Therefore, to avoid copying garbage afterwards when calling
gnet_stats_finish_copy(), this data is better copied to a dynamically allocated
memory that gets freed after use.
[xiyou.wangcong@gmail.com: remove a useless kfree()]
Signed-off-by: Ignacy Gawędzki <ignacy.gawedzki@green-communications.fr>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/gen_stats.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/net/core/gen_stats.c b/net/core/gen_stats.c index 0c08062d1796..1e2f46a69d50 100644 --- a/net/core/gen_stats.c +++ b/net/core/gen_stats.c @@ -32,6 +32,9 @@ gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size) return 0; nla_put_failure: + kfree(d->xstats); + d->xstats = NULL; + d->xstats_len = 0; spin_unlock_bh(d->lock); return -1; } @@ -305,7 +308,9 @@ int gnet_stats_copy_app(struct gnet_dump *d, void *st, int len) { if (d->compat_xstats) { - d->xstats = st; + d->xstats = kmemdup(st, len, GFP_ATOMIC); + if (!d->xstats) + goto err_out; d->xstats_len = len; } @@ -313,6 +318,11 @@ gnet_stats_copy_app(struct gnet_dump *d, void *st, int len) return gnet_stats_copy(d, TCA_STATS_APP, st, len); return 0; + +err_out: + d->xstats_len = 0; + spin_unlock_bh(d->lock); + return -1; } EXPORT_SYMBOL(gnet_stats_copy_app); @@ -345,6 +355,9 @@ gnet_stats_finish_copy(struct gnet_dump *d) return -1; } + kfree(d->xstats); + d->xstats = NULL; + d->xstats_len = 0; spin_unlock_bh(d->lock); return 0; } |