This is a note to let you know that I've just added the patch titled
lib: objagg: Fix general protection fault
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
lib-objagg-fix-general-protection-fault.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7ef997e3eb97ed65af5cd5f4ccbf7ca23e6fe12a
Author: Ido Schimmel <idosch@xxxxxxxxxx>
Date: Thu Jun 6 16:49:41 2024 +0200
lib: objagg: Fix general protection fault
[ Upstream commit b4a3a89fffcdf09702b1f161b914e52abca1894d ]
The library supports aggregation of objects into other objects only if
the parent object does not have a parent itself. That is, nesting is not
supported.
Aggregation happens in two cases: Without and with hints, where hints
are a pre-computed recommendation on how to aggregate the provided
objects.
Nesting is not possible in the first case due to a check that prevents
it, but in the second case there is no check because the assumption is
that nesting cannot happen when creating objects based on hints. The
violation of this assumption leads to various warnings and eventually to
a general protection fault [1].
Before fixing the root cause, error out when nesting happens and warn.
[1]
general protection fault, probably for non-canonical address 0xdead000000000d90: 0000 [#1] PREEMPT SMP PTI
CPU: 1 PID: 1083 Comm: kworker/1:9 Tainted: G W 6.9.0-rc6-custom-gd9b4f1cca7fb #7
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
RIP: 0010:mlxsw_sp_acl_erp_bf_insert+0x25/0x80
[...]
Call Trace:
<TASK>
mlxsw_sp_acl_atcam_entry_add+0x256/0x3c0
mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0
mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270
mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510
process_one_work+0x151/0x370
worker_thread+0x2cb/0x3e0
kthread+0xd0/0x100
ret_from_fork+0x34/0x50
ret_from_fork_asm+0x1a/0x30
</TASK>
Fixes: 9069a3817d82 ("lib: objagg: implement optimization hints assembly and use hints for object creation")
Reported-by: Alexander Zubkov <green@xxxxxxxxxx>
Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxx>
Reviewed-by: Amit Cohen <amcohen@xxxxxxxxxx>
Tested-by: Alexander Zubkov <green@xxxxxxxxxx>
Signed-off-by: Petr Machata <petrm@xxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/lib/objagg.c b/lib/objagg.c
index 55621fb82e0a3..e380e95de7702 100644
--- a/lib/objagg.c
+++ b/lib/objagg.c
@@ -167,6 +167,9 @@ static int objagg_obj_parent_assign(struct objagg *objagg,
{
void *delta_priv;
+ if (WARN_ON(!objagg_obj_is_root(parent)))
+ return -EINVAL;
+
delta_priv = objagg->ops->delta_create(objagg->priv, parent->obj,
objagg_obj->obj);
if (IS_ERR(delta_priv))
