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| author | Hangyu Hua <hbh25y@gmail.com> | 2022-06-01 09:46:25 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-29 18:05:45 +0300 |
| commit | 5aff12fa09504c6ea88fc17749a39cda2c4d6ef7 (patch) | |
| tree | e344453557a2a2c39ceaf9246a4462d7aa5c6a96 | |
| parent | 2994afca324aa584b8c1ca9a4facd4fae9746cf0 (diff) | |
| download | linux-5aff12fa09504c6ea88fc17749a39cda2c4d6ef7.tar.xz | |
xfrm: xfrm_policy: fix a possible double xfrm_pols_put() in xfrm_bundle_lookup()
[ Upstream commit f85daf0e725358be78dfd208dea5fd665d8cb901 ]
xfrm_policy_lookup() will call xfrm_pol_hold_rcu() to get a refcount of
pols[0]. This refcount can be dropped in xfrm_expand_policies() when
xfrm_expand_policies() return error. pols[0]'s refcount is balanced in
here. But xfrm_bundle_lookup() will also call xfrm_pols_put() with
num_pols == 1 to drop this refcount when xfrm_expand_policies() return
error.
This patch also fix an illegal address access. pols[0] will save a error
point when xfrm_policy_lookup fails. This lead to xfrm_pols_put to resolve
an illegal address in xfrm_bundle_lookup's error path.
Fix these by setting num_pols = 0 in xfrm_expand_policies()'s error path.
Fixes: 80c802f3073e ("xfrm: cache bundles instead of policies for outgoing flows")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/xfrm/xfrm_policy.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 9179b47e8b61..0894108f561c 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -1819,8 +1819,10 @@ static int xfrm_expand_policies(const struct flowi *fl, u16 family, *num_xfrms = 0; return 0; } - if (IS_ERR(pols[0])) + if (IS_ERR(pols[0])) { + *num_pols = 0; return PTR_ERR(pols[0]); + } *num_xfrms = pols[0]->xfrm_nr; @@ -1834,6 +1836,7 @@ static int xfrm_expand_policies(const struct flowi *fl, u16 family, if (pols[1]) { if (IS_ERR(pols[1])) { xfrm_pols_put(pols, *num_pols); + *num_pols = 0; return PTR_ERR(pols[1]); } (*num_pols)++; |