| Message ID | 20240419191200.219548-1-dtokazaki@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3] eeprom: at24: fix memory corruption race condition | expand |
On Fri, Apr 19, 2024 at 07:12:00PM +0000, Daniel Okazaki wrote: > If the eeprom is not accessible, an nvmem device will be registered, the > read will fail, and the device will be torn down. If another driver > accesses the nvmem device after the teardown, it will reference > invalid memory. > > Move the failure point before registering the nvmem device. > > Signed-off-by: Daniel Okazaki <dtokazaki@google.com> > Fixes: b20eb4c1f026 ("eeprom: at24: drop unnecessary label") > --- > drivers/misc/eeprom/at24.c | 18 +++++++++--------- > 1 file changed, 9 insertions(+), 9 deletions(-) > > diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c > index 572333ead5fb..4bd4f32bcdab 100644 > --- a/drivers/misc/eeprom/at24.c > +++ b/drivers/misc/eeprom/at24.c > @@ -758,15 +758,6 @@ static int at24_probe(struct i2c_client *client) > } > pm_runtime_enable(dev); > > - at24->nvmem = devm_nvmem_register(dev, &nvmem_config); > - if (IS_ERR(at24->nvmem)) { > - pm_runtime_disable(dev); > - if (!pm_runtime_status_suspended(dev)) > - regulator_disable(at24->vcc_reg); > - return dev_err_probe(dev, PTR_ERR(at24->nvmem), > - "failed to register nvmem\n"); > - } > - > /* > * Perform a one-byte test read to verify that the chip is functional, > * unless powering on the device is to be avoided during probe (i.e. > @@ -782,6 +773,15 @@ static int at24_probe(struct i2c_client *client) > } > } > > + at24->nvmem = devm_nvmem_register(dev, &nvmem_config); > + if (IS_ERR(at24->nvmem)) { > + pm_runtime_disable(dev); > + if (!pm_runtime_status_suspended(dev)) > + regulator_disable(at24->vcc_reg); > + return dev_err_probe(dev, PTR_ERR(at24->nvmem), > + "failed to register nvmem\n"); > + } > + > /* If this a SPD EEPROM, probe for DDR3 thermal sensor */ > if (cdata == &at24_data_spd) > at24_probe_temp_sensor(client); > -- > 2.44.0.769.g3c40516874-goog > Hi, This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him a patch that has triggered this response. He used to manually respond to these common problems, but in order to save his sanity (he kept writing the same thing over and over, yet to different people), I was created. Hopefully you will not take offence and will fix the problem in your patch and resubmit it so that it can be accepted into the Linux kernel tree. You are receiving this message because of the following common error(s) as indicated below: - This looks like a new version of a previously submitted patch, but you did not list below the --- line any changes from the previous version. Please read the section entitled "The canonical patch format" in the kernel file, Documentation/process/submitting-patches.rst for what needs to be done here to properly describe this. If you wish to discuss this problem further, or you have questions about how to resolve this issue, please feel free to respond to this email and Greg will reply once he has dug out from the pending patches received from other developers. thanks, greg k-h's patch email bot
On Sat, Apr 20, 2024 at 11:11:05AM +0200, Markus Elfring wrote: > > If the eeprom is not accessible, an nvmem device will be registered, the > > read will fail, and the device will be torn down. > … > > Can it be nicer to present the introduction for failure conditions as an enumeration? > > > > Move the failure point before registering the nvmem device. > … > > I would interpret the diff data more in the way that a devm_nvmem_register() call > should be performed a bit later in the implementation of the function “at24_probe”. > How do you think about to mention the affected function also in the summary phrase? > Hi, This is the semi-friendly patch-bot of Greg Kroah-Hartman. Markus, you seem to have sent a nonsensical or otherwise pointless review comment to a patch submission on a Linux kernel developer mailing list. I strongly suggest that you not do this anymore. Please do not bother developers who are actively working to produce patches and features with comments that, in the end, are a waste of time. Patch submitter, please ignore Markus's suggestion; you do not need to follow it at all. The person/bot/AI that sent it is being ignored by almost all Linux kernel maintainers for having a persistent pattern of behavior of producing distracting and pointless commentary, and inability to adapt to feedback. Please feel free to also ignore emails from them. thanks, greg k-h's patch email bot
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c index 572333ead5fb..4bd4f32bcdab 100644 --- a/drivers/misc/eeprom/at24.c +++ b/drivers/misc/eeprom/at24.c @@ -758,15 +758,6 @@ static int at24_probe(struct i2c_client *client) } pm_runtime_enable(dev); - at24->nvmem = devm_nvmem_register(dev, &nvmem_config); - if (IS_ERR(at24->nvmem)) { - pm_runtime_disable(dev); - if (!pm_runtime_status_suspended(dev)) - regulator_disable(at24->vcc_reg); - return dev_err_probe(dev, PTR_ERR(at24->nvmem), - "failed to register nvmem\n"); - } - /* * Perform a one-byte test read to verify that the chip is functional, * unless powering on the device is to be avoided during probe (i.e. @@ -782,6 +773,15 @@ static int at24_probe(struct i2c_client *client) } } + at24->nvmem = devm_nvmem_register(dev, &nvmem_config); + if (IS_ERR(at24->nvmem)) { + pm_runtime_disable(dev); + if (!pm_runtime_status_suspended(dev)) + regulator_disable(at24->vcc_reg); + return dev_err_probe(dev, PTR_ERR(at24->nvmem), + "failed to register nvmem\n"); + } + /* If this a SPD EEPROM, probe for DDR3 thermal sensor */ if (cdata == &at24_data_spd) at24_probe_temp_sensor(client);
If the eeprom is not accessible, an nvmem device will be registered, the read will fail, and the device will be torn down. If another driver accesses the nvmem device after the teardown, it will reference invalid memory. Move the failure point before registering the nvmem device. Signed-off-by: Daniel Okazaki <dtokazaki@google.com> Fixes: b20eb4c1f026 ("eeprom: at24: drop unnecessary label") --- drivers/misc/eeprom/at24.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)