diff options
| author |   blambert <blambert@openbsd.org> | 2011-05-11 07:37:04 +0000 |
|---|---|---|
| committer | blambert <blambert@openbsd.org> | 2011-05-11 07:37:04 +0000 |
| commit | f00cd271ecb8d50b616630d9e8f22ce41219a0c9 (patch) | |
| tree | 8cf5772cae11174312ed799862bcc594457e404a | |
| parent | Tweak previous from jmc@ (diff) | |
| download | wireguard-openbsd-f00cd271ecb8d50b616630d9e8f22ce41219a0c9.tar.xz wireguard-openbsd-f00cd271ecb8d50b616630d9e8f22ce41219a0c9.zip | |
Pre-allocate memory to avoid sleeping after performing a lookup, which
may lead to a race.
ok markus@ mikeb@
| -rw-r--r-- | sys/netinet/ip_ipsp.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/sys/netinet/ip_ipsp.c b/sys/netinet/ip_ipsp.c index c8a90947756..e93c5b0c571 100644 --- a/sys/netinet/ip_ipsp.c +++ b/sys/netinet/ip_ipsp.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ip_ipsp.c,v 1.182 2011/03/31 10:36:42 jasper Exp $ */ +/* $OpenBSD: ip_ipsp.c,v 1.183 2011/05/11 07:37:04 blambert Exp $ */ /* * The authors of this code are John Ioannidis (ji@tla.org), * Angelos D. Keromytis (kermit@csd.uch.gr), @@ -197,7 +197,7 @@ reserve_spi(u_int rdomain, u_int32_t sspi, u_int32_t tspi, union sockaddr_union *src, union sockaddr_union *dst, u_int8_t sproto, int *errval) { - struct tdb *tdbp; + struct tdb *tdbp, *exists; u_int32_t spi; int nums, s; @@ -236,6 +236,9 @@ reserve_spi(u_int rdomain, u_int32_t sspi, u_int32_t tspi, else nums = 100; /* Arbitrarily chosen */ + /* allocate ahead of time to avoid potential sleeping race in loop */ + tdbp = tdb_alloc(rdomain); + while (nums--) { if (sspi == tspi) /* Specific SPI asked. */ spi = tspi; @@ -250,13 +253,12 @@ reserve_spi(u_int rdomain, u_int32_t sspi, u_int32_t tspi, /* Check whether we're using this SPI already. */ s = spltdb(); - tdbp = gettdb(rdomain, spi, dst, sproto); + exists = gettdb(rdomain, spi, dst, sproto); splx(s); - if (tdbp != (struct tdb *) NULL) + if (exists) continue; - tdbp = tdb_alloc(rdomain); tdbp->tdb_spi = spi; bcopy(&dst->sa, &tdbp->tdb_dst.sa, SA_LEN(&dst->sa)); @@ -278,6 +280,7 @@ reserve_spi(u_int rdomain, u_int32_t sspi, u_int32_t tspi, } (*errval) = EEXIST; + tdb_free(tdbp); return 0; } |