6.6-stable review patch. If anyone has any objections, please let me know.
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From: Shay Drory shayd@nvidia.com
[ Upstream commit d62b14045c6511a7b2d4948d1a83a4e592deeb05 ]
Command bitmask have a dedicated bit for MANAGE_PAGES command, this bit isn't Initialize during command bitmask Initialization, only during MANAGE_PAGES.
In addition, mlx5_cmd_trigger_completions() is trying to trigger completion for MANAGE_PAGES command as well.
Hence, in case health error occurred before any MANAGE_PAGES command have been invoke (for example, during mlx5_enable_hca()), mlx5_cmd_trigger_completions() will try to trigger completion for MANAGE_PAGES command, which will result in null-ptr-deref error.[1]
Fix it by Initialize command bitmask correctly.
While at it, re-write the code for better understanding.
[1] BUG: KASAN: null-ptr-deref in mlx5_cmd_trigger_completions+0x1db/0x600 [mlx5_core] Write of size 4 at addr 0000000000000214 by task kworker/u96:2/12078 CPU: 10 PID: 12078 Comm: kworker/u96:2 Not tainted 6.9.0-rc2_for_upstream_debug_2024_04_07_19_01 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 Workqueue: mlx5_health0000:08:00.0 mlx5_fw_fatal_reporter_err_work [mlx5_core] Call Trace: <TASK> dump_stack_lvl+0x7e/0xc0 kasan_report+0xb9/0xf0 kasan_check_range+0xec/0x190 mlx5_cmd_trigger_completions+0x1db/0x600 [mlx5_core] mlx5_cmd_flush+0x94/0x240 [mlx5_core] enter_error_state+0x6c/0xd0 [mlx5_core] mlx5_fw_fatal_reporter_err_work+0xf3/0x480 [mlx5_core] process_one_work+0x787/0x1490 ? lockdep_hardirqs_on_prepare+0x400/0x400 ? pwq_dec_nr_in_flight+0xda0/0xda0 ? assign_work+0x168/0x240 worker_thread+0x586/0xd30 ? rescuer_thread+0xae0/0xae0 kthread+0x2df/0x3b0 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x2d/0x70 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork_asm+0x11/0x20 </TASK>
Fixes: 9b98d395b85d ("net/mlx5: Start health poll at earlier stage of driver load") Signed-off-by: Shay Drory shayd@nvidia.com Reviewed-by: Moshe Shemesh moshe@nvidia.com Reviewed-by: Saeed Mahameed saeedm@nvidia.com Signed-off-by: Tariq Toukan tariqt@nvidia.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index 48dc4ae87af09..80af0fc7101fd 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -1758,6 +1758,10 @@ static void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, u64 vec, bool force } }
+#define MLX5_MAX_MANAGE_PAGES_CMD_ENT 1 +#define MLX5_CMD_MASK ((1UL << (cmd->vars.max_reg_cmds + \ + MLX5_MAX_MANAGE_PAGES_CMD_ENT)) - 1) + static void mlx5_cmd_trigger_completions(struct mlx5_core_dev *dev) { struct mlx5_cmd *cmd = &dev->cmd; @@ -1769,7 +1773,7 @@ static void mlx5_cmd_trigger_completions(struct mlx5_core_dev *dev) /* wait for pending handlers to complete */ mlx5_eq_synchronize_cmd_irq(dev); spin_lock_irqsave(&dev->cmd.alloc_lock, flags); - vector = ~dev->cmd.vars.bitmask & ((1ul << (1 << dev->cmd.vars.log_sz)) - 1); + vector = ~dev->cmd.vars.bitmask & MLX5_CMD_MASK; if (!vector) goto no_trig;
@@ -2275,7 +2279,7 @@ int mlx5_cmd_enable(struct mlx5_core_dev *dev)
cmd->state = MLX5_CMDIF_STATE_DOWN; cmd->vars.max_reg_cmds = (1 << cmd->vars.log_sz) - 1; - cmd->vars.bitmask = (1UL << cmd->vars.max_reg_cmds) - 1; + cmd->vars.bitmask = MLX5_CMD_MASK;
sema_init(&cmd->vars.sem, cmd->vars.max_reg_cmds); sema_init(&cmd->vars.pages_sem, 1);