From: Kees Cook Date: Fri, 22 Sep 2023 17:49:59 +0000 (-0700) Subject: i2c: mux: demux-pinctrl: Annotate struct i2c_demux_pinctrl_priv with __counted_by X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=86f8a1ef96819d2ae62eaf3d89a0f0404348daa3;p=linux.git i2c: mux: demux-pinctrl: Annotate struct i2c_demux_pinctrl_priv with __counted_by Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct i2c_demux_pinctrl_priv. Additionally, since the element count member must be set before accessing the annotated flexible array member, move its initialization earlier. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva [wsa: improved blank lines] Signed-off-by: Wolfram Sang --- diff --git a/drivers/i2c/muxes/i2c-demux-pinctrl.c b/drivers/i2c/muxes/i2c-demux-pinctrl.c index a3a122fae71e0..ee5fb60651e79 100644 --- a/drivers/i2c/muxes/i2c-demux-pinctrl.c +++ b/drivers/i2c/muxes/i2c-demux-pinctrl.c @@ -32,7 +32,7 @@ struct i2c_demux_pinctrl_priv { const char *bus_name; struct i2c_adapter cur_adap; struct i2c_algorithm algo; - struct i2c_demux_pinctrl_chan chan[]; + struct i2c_demux_pinctrl_chan chan[] __counted_by(num_chan); }; static int i2c_demux_master_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) @@ -226,6 +226,8 @@ static int i2c_demux_pinctrl_probe(struct platform_device *pdev) if (!priv || !props) return -ENOMEM; + priv->num_chan = num_chan; + err = of_property_read_string(np, "i2c-bus-name", &priv->bus_name); if (err) return err; @@ -249,9 +251,7 @@ static int i2c_demux_pinctrl_probe(struct platform_device *pdev) of_changeset_update_property(&priv->chan[i].chgset, adap_np, &props[i]); } - priv->num_chan = num_chan; priv->dev = &pdev->dev; - platform_set_drvdata(pdev, priv); pm_runtime_no_callbacks(&pdev->dev);