6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Shay Drory <shayd@xxxxxxxxxx>
[ 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@xxxxxxxxxx>
Reviewed-by: Moshe Shemesh <moshe@xxxxxxxxxx>
Reviewed-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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);
--
2.43.0
