The endianness of a variable written to the measurement list cannot be
determined at compile time, as it depends on the value of the
ima_canonical_fmt global variable (set through a kernel option with the
same name if the machine is big endian).
If ima_canonical_fmt is false, the endianness of a variable is the same as
the machine; if ima_canonical_fmt is true, the endianness is little endian.
The warning arises due to this type of instruction:
var = cpu_to_leXX(var)
which tries to assign a value in little endian to a variable with native
endianness (little or big endian).
Given that the variables set with this instruction are not used in any
operation but just written to a buffer, it is safe to force the type of the
value being set to be the same of the type of the variable with:
var = (__force <var type>)cpu_to_leXX(var)
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
---
security/integrity/evm/evm_main.c | 2 +-
security/integrity/ima/ima_crypto.c | 4 ++--
security/integrity/ima/ima_fs.c | 6 +++---
security/integrity/ima/ima_template_lib.c | 11 ++++++-----
4 files changed, 12 insertions(+), 11 deletions(-)
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 2c226e634ae9..977208aecd06 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -360,7 +360,7 @@ int evm_read_protected_xattrs(struct dentry *dentry, u8 *buffer,
size = sizeof(u32);
if (buffer) {
if (canonical_fmt)
- rc = cpu_to_le32(rc);
+ rc = (__force int)cpu_to_le32(rc);
*(u32 *)(buffer + total_size) = rc;
}
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index f6a7e9643b54..a7206cc1d7d1 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -598,8 +598,8 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
u8 buffer[IMA_EVENT_NAME_LEN_MAX + 1] = { 0 };
u8 *data_to_hash = field_data[i].data;
u32 datalen = field_data[i].len;
- u32 datalen_to_hash =
- !ima_canonical_fmt ? datalen : cpu_to_le32(datalen);
+ u32 datalen_to_hash = !ima_canonical_fmt ?
+ datalen : (__force u32)cpu_to_le32(datalen);
if (strcmp(td->name, IMA_TEMPLATE_IMA_NAME) != 0) {
rc = crypto_shash_update(shash,
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index ea8ff8a07b36..3d8e9d5db5aa 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -147,7 +147,7 @@ int ima_measurements_show(struct seq_file *m, void *v)
* PCR used defaults to the same (config option) in
* little-endian format, unless set in policy
*/
- pcr = !ima_canonical_fmt ? e->pcr : cpu_to_le32(e->pcr);
+ pcr = !ima_canonical_fmt ? e->pcr : (__force u32)cpu_to_le32(e->pcr);
ima_putc(m, &pcr, sizeof(e->pcr));
/* 2nd: template digest */
@@ -155,7 +155,7 @@ int ima_measurements_show(struct seq_file *m, void *v)
/* 3rd: template name size */
namelen = !ima_canonical_fmt ? strlen(template_name) :
- cpu_to_le32(strlen(template_name));
+ (__force u32)cpu_to_le32(strlen(template_name));
ima_putc(m, &namelen, sizeof(namelen));
/* 4th: template name */
@@ -167,7 +167,7 @@ int ima_measurements_show(struct seq_file *m, void *v)
if (!is_ima_template) {
template_data_len = !ima_canonical_fmt ? e->template_data_len :
- cpu_to_le32(e->template_data_len);
+ (__force u32)cpu_to_le32(e->template_data_len);
ima_putc(m, &template_data_len, sizeof(e->template_data_len));
}
diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index 3f8d53a03612..8e2a121af5e1 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -133,7 +133,8 @@ static void ima_show_template_data_binary(struct seq_file *m,
strlen(field_data->data) : field_data->len;
if (show != IMA_SHOW_BINARY_NO_FIELD_LEN) {
- u32 field_len = !ima_canonical_fmt ? len : cpu_to_le32(len);
+ u32 field_len = !ima_canonical_fmt ?
+ len : (__force u32)cpu_to_le32(len);
ima_putc(m, &field_len, sizeof(field_len));
}
@@ -570,9 +571,9 @@ static int ima_eventinodedac_init_common(struct ima_event_data *event_data,
if (ima_canonical_fmt) {
if (sizeof(id) == sizeof(u16))
- id = cpu_to_le16(id);
+ id = (__force u16)cpu_to_le16(id);
else
- id = cpu_to_le32(id);
+ id = (__force u32)cpu_to_le32(id);
}
return ima_write_template_field_data((void *)&id, sizeof(id),
@@ -607,7 +608,7 @@ int ima_eventinodemode_init(struct ima_event_data *event_data,
struct ima_field_data *field_data)
{
struct inode *inode;
- umode_t mode;
+ u16 mode;
if (!event_data->file)
return 0;
@@ -615,7 +616,7 @@ int ima_eventinodemode_init(struct ima_event_data *event_data,
inode = file_inode(event_data->file);
mode = inode->i_mode;
if (ima_canonical_fmt)
- mode = cpu_to_le16(mode);
+ mode = (__force u16)cpu_to_le16(mode);
return ima_write_template_field_data((char *)&mode, sizeof(mode),
DATA_FMT_UINT, field_data);
--
2.25.1
