[PATCH AUTOSEL 5.4 181/459] Revert "nfp: abm: fix memory leak in nfp_abm_u32_knode_replace"

From: Sasha Levin
Date: Fri Feb 14 2020 - 12:35:55 EST


From: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>

[ Upstream commit 1d1997db870f4058676439ef7014390ba9e24eb2 ]

This reverts commit 78beef629fd9 ("nfp: abm: fix memory leak in
nfp_abm_u32_knode_replace").

The quoted commit does not fix anything and resulted in a bogus
CVE-2019-19076.

If match is NULL then it is known there is no matching entry in
list, hence, calling nfp_abm_u32_knode_delete() is pointless.

Signed-off-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
Reviewed-by: John Hurley <john.hurley@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/netronome/nfp/abm/cls.c | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/abm/cls.c b/drivers/net/ethernet/netronome/nfp/abm/cls.c
index 9f8a1f69c0c4c..23ebddfb95325 100644
--- a/drivers/net/ethernet/netronome/nfp/abm/cls.c
+++ b/drivers/net/ethernet/netronome/nfp/abm/cls.c
@@ -176,10 +176,8 @@ nfp_abm_u32_knode_replace(struct nfp_abm_link *alink,
u8 mask, val;
int err;

- if (!nfp_abm_u32_check_knode(alink->abm, knode, proto, extack)) {
- err = -EOPNOTSUPP;
+ if (!nfp_abm_u32_check_knode(alink->abm, knode, proto, extack))
goto err_delete;
- }

tos_off = proto == htons(ETH_P_IP) ? 16 : 20;

@@ -200,18 +198,14 @@ nfp_abm_u32_knode_replace(struct nfp_abm_link *alink,
if ((iter->val & cmask) == (val & cmask) &&
iter->band != knode->res->classid) {
NL_SET_ERR_MSG_MOD(extack, "conflict with already offloaded filter");
- err = -EOPNOTSUPP;
goto err_delete;
}
}

if (!match) {
match = kzalloc(sizeof(*match), GFP_KERNEL);
- if (!match) {
- err = -ENOMEM;
- goto err_delete;
- }
-
+ if (!match)
+ return -ENOMEM;
list_add(&match->list, &alink->dscp_map);
}
match->handle = knode->handle;
@@ -227,7 +221,7 @@ nfp_abm_u32_knode_replace(struct nfp_abm_link *alink,

err_delete:
nfp_abm_u32_knode_delete(alink, knode);
- return err;
+ return -EOPNOTSUPP;
}

static int nfp_abm_setup_tc_block_cb(enum tc_setup_type type,
--
2.20.1