From b666c7e86b3d6db69305243224dc3292f724539f Mon Sep 17 00:00:00 2001 From: Moshe Shemesh Date: Mon, 28 Nov 2022 19:05:47 +0200 Subject: [PATCH] net/mlx5: Fix command stats access after free [ Upstream commit da2e552b469a0cd130ff70a88ccc4139da428a65 ] Command may fail while driver is reloading and can't accept FW commands till command interface is reinitialized. Such command failure is being logged to command stats. This results in NULL pointer access as command stats structure is being freed and reallocated during mlx5 devlink reload (see kernel log below). Fix it by making command stats statically allocated on driver probe. Kernel log: [ 2394.808802] BUG: unable to handle kernel paging request at 000000000002a9c0 [ 2394.810610] PGD 0 P4D 0 [ 2394.811811] Oops: 0002 [#1] SMP NOPTI ... [ 2394.815482] RIP: 0010:native_queued_spin_lock_slowpath+0x183/0x1d0 ... [ 2394.829505] Call Trace: [ 2394.830667] _raw_spin_lock_irq+0x23/0x26 [ 2394.831858] cmd_status_err+0x55/0x110 [mlx5_core] [ 2394.833020] mlx5_access_reg+0xe7/0x150 [mlx5_core] [ 2394.834175] mlx5_query_port_ptys+0x78/0xa0 [mlx5_core] [ 2394.835337] mlx5e_ethtool_get_link_ksettings+0x74/0x590 [mlx5_core] [ 2394.836454] ? kmem_cache_alloc_trace+0x140/0x1c0 [ 2394.837562] __rh_call_get_link_ksettings+0x33/0x100 [ 2394.838663] ? __rtnl_unlock+0x25/0x50 [ 2394.839755] __ethtool_get_link_ksettings+0x72/0x150 [ 2394.840862] duplex_show+0x6e/0xc0 [ 2394.841963] dev_attr_show+0x1c/0x40 [ 2394.843048] sysfs_kf_seq_show+0x9b/0x100 [ 2394.844123] seq_read+0x153/0x410 [ 2394.845187] vfs_read+0x91/0x140 [ 2394.846226] ksys_read+0x4f/0xb0 [ 2394.847234] do_syscall_64+0x5b/0x1a0 [ 2394.848228] entry_SYSCALL_64_after_hwframe+0x65/0xca Fixes: 76f176115dca ("net/mlx5: Add command failures data to debugfs") Signed-off-by: Moshe Shemesh Reviewed-by: Shay Drory Signed-off-by: Saeed Mahameed Signed-off-by: Sasha Levin --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 13 ++----------- include/linux/mlx5/driver.h | 2 +- 2 files changed, 3 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index e7a894ba5c3ea..723891eb86eec 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -2177,15 +2177,9 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev) return -EINVAL; } - cmd->stats = kvcalloc(MLX5_CMD_OP_MAX, sizeof(*cmd->stats), GFP_KERNEL); - if (!cmd->stats) - return -ENOMEM; - cmd->pool = dma_pool_create("mlx5_cmd", mlx5_core_dma_dev(dev), size, align, 0); - if (!cmd->pool) { - err = -ENOMEM; - goto dma_pool_err; - } + if (!cmd->pool) + return -ENOMEM; err = alloc_cmd_page(dev, cmd); if (err) @@ -2269,8 +2263,6 @@ err_free_page: err_free_pool: dma_pool_destroy(cmd->pool); -dma_pool_err: - kvfree(cmd->stats); return err; } @@ -2283,7 +2275,6 @@ void mlx5_cmd_cleanup(struct mlx5_core_dev *dev) destroy_msg_cache(dev); free_cmd_page(dev, cmd); dma_pool_destroy(cmd->pool); - kvfree(cmd->stats); } void mlx5_cmd_set_state(struct mlx5_core_dev *dev, diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index 06cbad166225a..ad55470a9fb97 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -315,7 +315,7 @@ struct mlx5_cmd { struct mlx5_cmd_debug dbg; struct cmd_msg_cache cache[MLX5_NUM_COMMAND_CACHES]; int checksum_disabled; - struct mlx5_cmd_stats *stats; + struct mlx5_cmd_stats stats[MLX5_CMD_OP_MAX]; }; struct mlx5_cmd_mailbox { -- 2.39.5