diff mbox series

[SRU,J,1/1] mlxsw: spectrum_acl_tcam: Fix NULL pointer dereference in error path

Message ID 20241114055337.227010-3-jianhui.lee@canonical.com
State New
Headers show
Series CVE-2024-26595 | expand

Commit Message

Jian Hui Lee Nov. 14, 2024, 5:53 a.m. UTC
From: Ido Schimmel <idosch@nvidia.com>

When calling mlxsw_sp_acl_tcam_region_destroy() from an error path after
failing to attach the region to an ACL group, we hit a NULL pointer
dereference upon 'region->group->tcam' [1].

Fix by retrieving the 'tcam' pointer using mlxsw_sp_acl_to_tcam().

[1]
BUG: kernel NULL pointer dereference, address: 0000000000000000
[...]
RIP: 0010:mlxsw_sp_acl_tcam_region_destroy+0xa0/0xd0
[...]
Call Trace:
 mlxsw_sp_acl_tcam_vchunk_get+0x88b/0xa20
 mlxsw_sp_acl_tcam_ventry_add+0x25/0xe0
 mlxsw_sp_acl_rule_add+0x47/0x240
 mlxsw_sp_flower_replace+0x1a9/0x1d0
 tc_setup_cb_add+0xdc/0x1c0
 fl_hw_replace_filter+0x146/0x1f0
 fl_change+0xc17/0x1360
 tc_new_tfilter+0x472/0xb90
 rtnetlink_rcv_msg+0x313/0x3b0
 netlink_rcv_skb+0x58/0x100
 netlink_unicast+0x244/0x390
 netlink_sendmsg+0x1e4/0x440
 ____sys_sendmsg+0x164/0x260
 ___sys_sendmsg+0x9a/0xe0
 __sys_sendmsg+0x7a/0xc0
 do_syscall_64+0x40/0xe0
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Fixes: 22a677661f56 ("mlxsw: spectrum: Introduce ACL core with simple TCAM implementation")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/fb6a4542bbc9fcab5a523802d97059bffbca7126.1705502064.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
(backported from commit efeb7dfea8ee10cdec11b6b6ba4e405edbe75809 linux-stable)
[jianhuilee: although efeb7dfea8ee can be applied cleanly, it lacks the
wrapper mlxsw_sp_acl_to_tcam() introduced in 74cbc3c03c82 linux-stable,
which includes additional changes that are unnecessary for our use. a
more suitable approach would be to backport mlxsw_sp_acl_to_tcam()
within this patch.]
CVE-2024-26595
Signed-off-by: Jian Hui Lee <jianhui.lee@canonical.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum.h          | 1 +
 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c      | 5 +++++
 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c | 4 ++--
 3 files changed, 8 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index 3a43cba6d23c..fe949113294d 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -905,6 +905,7 @@  enum mlxsw_sp_acl_profile {
 };
 
 struct mlxsw_afk *mlxsw_sp_acl_afk(struct mlxsw_sp_acl *acl);
+struct mlxsw_sp_acl_tcam *mlxsw_sp_acl_to_tcam(struct mlxsw_sp_acl *acl);
 
 int mlxsw_sp_acl_ruleset_bind(struct mlxsw_sp *mlxsw_sp,
 			      struct mlxsw_sp_flow_block *block,
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
index 67cedfa76f78..6aa1b6065095 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
@@ -40,6 +40,11 @@  struct mlxsw_afk *mlxsw_sp_acl_afk(struct mlxsw_sp_acl *acl)
 	return acl->afk;
 }
 
+struct mlxsw_sp_acl_tcam *mlxsw_sp_acl_to_tcam(struct mlxsw_sp_acl *acl)
+{
+	return &acl->tcam;
+}
+
 struct mlxsw_sp_acl_ruleset_ht_key {
 	struct mlxsw_sp_flow_block *block;
 	u32 chain_index;
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c
index 46b1120a8151..59da5494bead 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c
@@ -680,13 +680,13 @@  static void
 mlxsw_sp_acl_tcam_region_destroy(struct mlxsw_sp *mlxsw_sp,
 				 struct mlxsw_sp_acl_tcam_region *region)
 {
+	struct mlxsw_sp_acl_tcam *tcam = mlxsw_sp_acl_to_tcam(mlxsw_sp->acl);
 	const struct mlxsw_sp_acl_tcam_ops *ops = mlxsw_sp->acl_tcam_ops;
 
 	ops->region_fini(mlxsw_sp, region->priv);
 	mlxsw_sp_acl_tcam_region_disable(mlxsw_sp, region);
 	mlxsw_sp_acl_tcam_region_free(mlxsw_sp, region);
-	mlxsw_sp_acl_tcam_region_id_put(region->group->tcam,
-					region->id);
+	mlxsw_sp_acl_tcam_region_id_put(tcam, region->id);
 	kfree(region);
 }