Created attachment 234460 [details] a possible patch mlx4_QP_FLOW_STEERING_DETACH_wrapper first removes the rrule and then references qpn field in rrule. The memory of rrule might be reallocated, making the pqn field different. Fix this by saving qpn in a local variable.
Thank you!
A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=dd2a8c8f72d369440c36f10512324d42ecedb5c7 commit dd2a8c8f72d369440c36f10512324d42ecedb5c7 Author: Hans Petter Selasky <hselasky@FreeBSD.org> AuthorDate: 2022-06-07 14:27:53 +0000 Commit: Hans Petter Selasky <hselasky@FreeBSD.org> CommitDate: 2022-06-07 14:28:32 +0000 mlx4core: Use-after-free causes a resource leak in flow-steering detach mlx4_QP_FLOW_STEERING_DETACH_wrapper first removes the steering rule (which results in freeing the rule structure), and then references a field in this struct (the qp number) when releasing the busy-status on the rule's qp. Since this memory was freed, it could reallocated and changed. Therefore, the qp number in the struct may be incorrect, so that we are releasing the incorrect qp. This leaves the rule's qp in the busy state (and could possibly release an incorrect qp as well). Fix this by saving the qp number in a local variable, for use after removing the steering rule. Linux commit: 3b01fe7f91c8e4f9afc4fae3c5af72c14958d2d8 PR: 264469 MFC after: 1 week Sponsored by: NVIDIA Networking sys/dev/mlx4/mlx4_core/mlx4_resource_tracker.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
A commit in branch stable/13 references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=be3f667388f42ac4bf4d7eaac0b3fef5dee86eac commit be3f667388f42ac4bf4d7eaac0b3fef5dee86eac Author: Hans Petter Selasky <hselasky@FreeBSD.org> AuthorDate: 2022-06-07 14:27:53 +0000 Commit: Hans Petter Selasky <hselasky@FreeBSD.org> CommitDate: 2022-06-14 09:39:23 +0000 mlx4core: Use-after-free causes a resource leak in flow-steering detach mlx4_QP_FLOW_STEERING_DETACH_wrapper first removes the steering rule (which results in freeing the rule structure), and then references a field in this struct (the qp number) when releasing the busy-status on the rule's qp. Since this memory was freed, it could reallocated and changed. Therefore, the qp number in the struct may be incorrect, so that we are releasing the incorrect qp. This leaves the rule's qp in the busy state (and could possibly release an incorrect qp as well). Fix this by saving the qp number in a local variable, for use after removing the steering rule. Linux commit: 3b01fe7f91c8e4f9afc4fae3c5af72c14958d2d8 PR: 264469 Sponsored by: NVIDIA Networking (cherry picked from commit dd2a8c8f72d369440c36f10512324d42ecedb5c7) sys/dev/mlx4/mlx4_core/mlx4_resource_tracker.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)