Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-14 23:25:54 +00:00
Code Issues Packages Projects Releases Wiki Activity

hwmon: (pmbus/max20730) Remove strlcpy occurences

Browse Source 
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with direct assignment.

strlcpy in this file is used to copy fixed-length strings which can be
completely avoided by direct assignment and is safe to do so. strlen()
is used to return the length of @tbuf.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230712214307.2424810-1-azeemshaikh38@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Azeem Shaikh 2023-07-12 21:43:07 +00:00 committed by Guenter Roeck
parent 39f034386f
commit 170fea8817
1 changed files with 33 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

64
drivers/hwmon/pmbus/max20730.c
View File

@ -114,6 +114,7 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
const struct pmbus_driver_info *info;
const struct max20730_data *data;
char tbuf[DEBUG_FS_DATA_MAX] = { 0 };
char *result = tbuf;
u16 val;
info = pmbus_get_driver_info(psu->client);
@ -148,13 +149,13 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
>> MAX20730_MFR_DEVSET1_TSTAT_BIT_POS;
if (val == 0)
len = strlcpy(tbuf, "2000\n", DEBUG_FS_DATA_MAX);
result = "2000\n";
else if (val == 1)
len = strlcpy(tbuf, "125\n", DEBUG_FS_DATA_MAX);
result = "125\n";
else if (val == 2)
len = strlcpy(tbuf, "62.5\n", DEBUG_FS_DATA_MAX);
result = "62.5\n";
else
len = strlcpy(tbuf, "32\n", DEBUG_FS_DATA_MAX);
result = "32\n";
break;
case MAX20730_DEBUGFS_INTERNAL_GAIN:
val = (data->mfr_devset1 & MAX20730_MFR_DEVSET1_RGAIN_MASK)
@ -163,35 +164,35 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
if (data->id == max20734) {
/* AN6209 */
if (val == 0)
len = strlcpy(tbuf, "0.8\n", DEBUG_FS_DATA_MAX);
result = "0.8\n";
else if (val == 1)
len = strlcpy(tbuf, "3.2\n", DEBUG_FS_DATA_MAX);
result = "3.2\n";
else if (val == 2)
len = strlcpy(tbuf, "1.6\n", DEBUG_FS_DATA_MAX);
result = "1.6\n";
else
len = strlcpy(tbuf, "6.4\n", DEBUG_FS_DATA_MAX);
result = "6.4\n";
} else if (data->id == max20730 || data->id == max20710) {
/* AN6042 or AN6140 */
if (val == 0)
len = strlcpy(tbuf, "0.9\n", DEBUG_FS_DATA_MAX);
result = "0.9\n";
else if (val == 1)
len = strlcpy(tbuf, "3.6\n", DEBUG_FS_DATA_MAX);
result = "3.6\n";
else if (val == 2)
len = strlcpy(tbuf, "1.8\n", DEBUG_FS_DATA_MAX);
result = "1.8\n";
else
len = strlcpy(tbuf, "7.2\n", DEBUG_FS_DATA_MAX);
result = "7.2\n";
} else if (data->id == max20743) {
/* AN6042 */
if (val == 0)
len = strlcpy(tbuf, "0.45\n", DEBUG_FS_DATA_MAX);
result = "0.45\n";
else if (val == 1)
len = strlcpy(tbuf, "1.8\n", DEBUG_FS_DATA_MAX);
result = "1.8\n";
else if (val == 2)
len = strlcpy(tbuf, "0.9\n", DEBUG_FS_DATA_MAX);
result = "0.9\n";
else
len = strlcpy(tbuf, "3.6\n", DEBUG_FS_DATA_MAX);
result = "3.6\n";
} else {
len = strlcpy(tbuf, "Not supported\n", DEBUG_FS_DATA_MAX);
result = "Not supported\n";
}
break;
case MAX20730_DEBUGFS_BOOT_VOLTAGE:
@ -199,26 +200,26 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
>> MAX20730_MFR_DEVSET1_VBOOT_BIT_POS;
if (val == 0)
len = strlcpy(tbuf, "0.6484\n", DEBUG_FS_DATA_MAX);
result = "0.6484\n";
else if (val == 1)
len = strlcpy(tbuf, "0.8984\n", DEBUG_FS_DATA_MAX);
result = "0.8984\n";
else if (val == 2)
len = strlcpy(tbuf, "1.0\n", DEBUG_FS_DATA_MAX);
result = "1.0\n";
else
len = strlcpy(tbuf, "Invalid\n", DEBUG_FS_DATA_MAX);
result = "Invalid\n";
break;
case MAX20730_DEBUGFS_OUT_V_RAMP_RATE:
val = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_VRATE)
>> MAX20730_MFR_DEVSET2_VRATE_BIT_POS;
if (val == 0)
len = strlcpy(tbuf, "4\n", DEBUG_FS_DATA_MAX);
result = "4\n";
else if (val == 1)
len = strlcpy(tbuf, "2\n", DEBUG_FS_DATA_MAX);
result = "2\n";
else if (val == 2)
len = strlcpy(tbuf, "1\n", DEBUG_FS_DATA_MAX);
result = "1\n";
else
len = strlcpy(tbuf, "Invalid\n", DEBUG_FS_DATA_MAX);
result = "Invalid\n";
break;
case MAX20730_DEBUGFS_OC_PROTECT_MODE:
ret = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_OCPM_MASK)
@ -230,13 +231,13 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
>> MAX20730_MFR_DEVSET2_SS_BIT_POS;
if (val == 0)
len = strlcpy(tbuf, "0.75\n", DEBUG_FS_DATA_MAX);
result = "0.75\n";
else if (val == 1)
len = strlcpy(tbuf, "1.5\n", DEBUG_FS_DATA_MAX);
result = "1.5\n";
else if (val == 2)
len = strlcpy(tbuf, "3\n", DEBUG_FS_DATA_MAX);
result = "3\n";
else
len = strlcpy(tbuf, "6\n", DEBUG_FS_DATA_MAX);
result = "6\n";
break;
case MAX20730_DEBUGFS_IMAX:
ret = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_IMAX_MASK)
@ -287,10 +288,11 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
"%d.%d\n", ret / 10000, ret % 10000);
break;
default:
len = strlcpy(tbuf, "Invalid\n", DEBUG_FS_DATA_MAX);
result = "Invalid\n";
}
return simple_read_from_buffer(buf, count, ppos, tbuf, len);
len = strlen(result);
return simple_read_from_buffer(buf, count, ppos, result, len);
}
static const struct file_operations max20730_fops = {