From 8200597fb16651e5b2280b694dd86352b738657b Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Thu, 25 Jun 2020 14:27:36 +0100 Subject: clk: vc5: fix use of memory after it has been kfree'd There are a several places where printing an error message of init.name occurs after init.name has been kfree'd. Also the failure message is duplicated each time in the code. Fix this by adding a registration error failure path for these cases, moving the duplicated error messages to one common point and kfree'ing init.name only after it has been used. Changes also shrink the object code size by 171 bytes (x86-64, gcc 9.3): Before: text data bss dec hex filename 21057 3960 64 25081 61f9 drivers/clk/clk-versaclock5.o After: text data bss dec hex filename 20886 3960 64 24910 614e drivers/clk/clk-versaclock5.o Addresses-Coverity: ("Use after free") Fixes: f491276a5168 ("clk: vc5: Allow Versaclock driver to support multiple instances") Signed-off-by: Colin Ian King Link: https://lore.kernel.org/r/20200625132736.88832-1-colin.king@canonical.com Reviewed-by: Luca Ceresoli [sboyd@kernel.org: Drop stray newline] Signed-off-by: Stephen Boyd --- drivers/clk/clk-versaclock5.c | 50 ++++++++++++++++--------------------------- 1 file changed, 18 insertions(+), 32 deletions(-) (limited to 'drivers/clk/clk-versaclock5.c') diff --git a/drivers/clk/clk-versaclock5.c b/drivers/clk/clk-versaclock5.c index 9a5fb3834b9a..d6fa15b6f37f 100644 --- a/drivers/clk/clk-versaclock5.c +++ b/drivers/clk/clk-versaclock5.c @@ -882,11 +882,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) init.parent_names = parent_names; vc5->clk_mux.init = &init; ret = devm_clk_hw_register(&client->dev, &vc5->clk_mux); + if (ret) + goto err_clk_register; kfree(init.name); /* clock framework made a copy of the name */ - if (ret) { - dev_err(&client->dev, "unable to register %s\n", init.name); - goto err_clk; - } if (vc5->chip_info->flags & VC5_HAS_PFD_FREQ_DBL) { /* Register frequency doubler */ @@ -900,12 +898,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) init.num_parents = 1; vc5->clk_mul.init = &init; ret = devm_clk_hw_register(&client->dev, &vc5->clk_mul); + if (ret) + goto err_clk_register; kfree(init.name); /* clock framework made a copy of the name */ - if (ret) { - dev_err(&client->dev, "unable to register %s\n", - init.name); - goto err_clk; - } } /* Register PFD */ @@ -921,11 +916,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) init.num_parents = 1; vc5->clk_pfd.init = &init; ret = devm_clk_hw_register(&client->dev, &vc5->clk_pfd); + if (ret) + goto err_clk_register; kfree(init.name); /* clock framework made a copy of the name */ - if (ret) { - dev_err(&client->dev, "unable to register %s\n", init.name); - goto err_clk; - } /* Register PLL */ memset(&init, 0, sizeof(init)); @@ -939,11 +932,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) vc5->clk_pll.vc5 = vc5; vc5->clk_pll.hw.init = &init; ret = devm_clk_hw_register(&client->dev, &vc5->clk_pll.hw); + if (ret) + goto err_clk_register; kfree(init.name); /* clock framework made a copy of the name */ - if (ret) { - dev_err(&client->dev, "unable to register %s\n", init.name); - goto err_clk; - } /* Register FODs */ for (n = 0; n < vc5->chip_info->clk_fod_cnt; n++) { @@ -960,12 +951,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) vc5->clk_fod[n].vc5 = vc5; vc5->clk_fod[n].hw.init = &init; ret = devm_clk_hw_register(&client->dev, &vc5->clk_fod[n].hw); + if (ret) + goto err_clk_register; kfree(init.name); /* clock framework made a copy of the name */ - if (ret) { - dev_err(&client->dev, "unable to register %s\n", - init.name); - goto err_clk; - } } /* Register MUX-connected OUT0_I2C_SELB output */ @@ -981,11 +969,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) vc5->clk_out[0].vc5 = vc5; vc5->clk_out[0].hw.init = &init; ret = devm_clk_hw_register(&client->dev, &vc5->clk_out[0].hw); - kfree(init.name); /* clock framework made a copy of the name */ - if (ret) { - dev_err(&client->dev, "unable to register %s\n", init.name); - goto err_clk; - } + if (ret) + goto err_clk_register; + kfree(init.name); /* clock framework made a copy of the name */ /* Register FOD-connected OUTx outputs */ for (n = 1; n < vc5->chip_info->clk_out_cnt; n++) { @@ -1008,12 +994,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) vc5->clk_out[n].vc5 = vc5; vc5->clk_out[n].hw.init = &init; ret = devm_clk_hw_register(&client->dev, &vc5->clk_out[n].hw); + if (ret) + goto err_clk_register; kfree(init.name); /* clock framework made a copy of the name */ - if (ret) { - dev_err(&client->dev, "unable to register %s\n", - init.name); - goto err_clk; - } /* Fetch Clock Output configuration from DT (if specified) */ ret = vc5_get_output_config(client, &vc5->clk_out[n]); @@ -1029,6 +1012,9 @@ static int vc5_probe(struct i2c_client *client, const struct i2c_device_id *id) return 0; +err_clk_register: + dev_err(&client->dev, "unable to register %s\n", init.name); + kfree(init.name); /* clock framework made a copy of the name */ err_clk: if (vc5->chip_info->flags & VC5_HAS_INTERNAL_XTAL) clk_unregister_fixed_rate(vc5->pin_xin); -- cgit v1.2.3