2008-03-21 23:01:37

by Chris Wright

[permalink] [raw]
Subject: [patch 14/76] IPCOMP: Disable BH on output when using shared tfm

-stable review patch. If anyone has any objections, please let us know.
---------------------

From: Herbert Xu <[email protected]>

Upstream commit: 21e43188f272c7fd9efc84b8244c0b1dfccaa105

Because we use shared tfm objects in order to conserve memory,
(each tfm requires 128K of vmalloc memory), BH needs to be turned
off on output as that can occur in process context.

Previously this was done implicitly by the xfrm output code.
That was lost when it became lockless. So we need to add the
BH disabling to IPComp directly.

Signed-off-by: Herbert Xu <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Chris Wright <[email protected]>

---
net/ipv4/ipcomp.c | 5 ++++-
net/ipv6/ipcomp6.c | 2 ++
2 files changed, 6 insertions(+), 1 deletion(-)

--- a/net/ipv4/ipcomp.c
+++ b/net/ipv4/ipcomp.c
@@ -108,8 +108,11 @@ static int ipcomp_compress(struct xfrm_s
const int cpu = get_cpu();
u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu);
struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu);
- int err = crypto_comp_compress(tfm, start, plen, scratch, &dlen);
+ int err;

+ local_bh_disable();
+ err = crypto_comp_compress(tfm, start, plen, scratch, &dlen);
+ local_bh_enable();
if (err)
goto out;

--- a/net/ipv6/ipcomp6.c
+++ b/net/ipv6/ipcomp6.c
@@ -146,7 +146,9 @@ static int ipcomp6_output(struct xfrm_st
scratch = *per_cpu_ptr(ipcomp6_scratches, cpu);
tfm = *per_cpu_ptr(ipcd->tfms, cpu);

+ local_bh_disable();
err = crypto_comp_compress(tfm, start, plen, scratch, &dlen);
+ local_bh_enable();
if (err || (dlen + sizeof(*ipch)) >= plen) {
put_cpu();
goto out_ok;

--