This reverts commit b401f8c4f492cbf74f3f59c9141e5be3071071bb.
The offending commit claimed that trying to set the values reported back
by TIOCGSERIAL as a regular user could result in an -EPERM error when HZ
is 250, but that was never the case.
With HZ=250, the default 0.5 second value of close_delay is converted to
125 jiffies when set and is converted back to 50 centiseconds by
TIOCGSERIAL as expected (not 12 cs as was claimed).
Comparing the internal current and new jiffies values is just fine to
determine if the value is about to change so drop the bogus workaround
(which was also backported to stable).
For completeness: With different default values for these parameters or
with a HZ value not divisible by two, the lack of rounding when setting
the default values in tty_port_init() could result in an -EPERM being
returned, but this is hardly something we need to worry about.
Cc: Anthony Mallet <anthony.mallet(a)laas.fr>
Cc: stable(a)vger.kernel.org
Signed-off-by: Johan Hovold <johan(a)kernel.org>
---
drivers/usb/class/cdc-acm.c | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 3fda1ec961d7..96e221803fa6 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -942,7 +942,6 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss)
{
struct acm *acm = tty->driver_data;
unsigned int closing_wait, close_delay;
- unsigned int old_closing_wait, old_close_delay;
int retval = 0;
close_delay = msecs_to_jiffies(ss->close_delay * 10);
@@ -950,17 +949,11 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss)
ASYNC_CLOSING_WAIT_NONE :
msecs_to_jiffies(ss->closing_wait * 10);
- /* we must redo the rounding here, so that the values match */
- old_close_delay = jiffies_to_msecs(acm->port.close_delay) / 10;
- old_closing_wait = acm->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
- ASYNC_CLOSING_WAIT_NONE :
- jiffies_to_msecs(acm->port.closing_wait) / 10;
-
mutex_lock(&acm->port.mutex);
if (!capable(CAP_SYS_ADMIN)) {
- if ((ss->close_delay != old_close_delay) ||
- (ss->closing_wait != old_closing_wait))
+ if ((close_delay != acm->port.close_delay) ||
+ (closing_wait != acm->port.closing_wait))
retval = -EPERM;
else
retval = -EOPNOTSUPP;
--
2.26.3
evm_inode_init_security() requires an HMAC key to calculate the HMAC on
initial xattrs provided by LSMs. However, it checks generically whether a
key has been loaded, including also public keys, which is not correct as
public keys are not suitable to calculate the HMAC.
Originally, support for signature verification was introduced to verify a
possibly immutable initial ram disk, when no new files are created, and to
switch to HMAC for the root filesystem. By that time, an HMAC key should
have been loaded and usable to calculate HMACs for new files.
More recently support for requiring an HMAC key was removed from the
kernel, so that signature verification can be used alone. Since this is a
legitimate use case, evm_inode_init_security() should not return an error
when no HMAC key has been loaded.
This patch fixes this problem by replacing the evm_key_loaded() check with
a check of the EVM_INIT_HMAC flag in evm_initialized.
Cc: stable(a)vger.kernel.org # 4.5.x
Fixes: 26ddabfe96b ("evm: enable EVM when X509 certificate is loaded")
Signed-off-by: Roberto Sassu <roberto.sassu(a)huawei.com>
Reviewed-by: Mimi Zohar <zohar(a)linux.ibm.com>
---
security/integrity/evm/evm_main.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 0de367aaa2d3..7ac5204c8d1f 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -521,7 +521,7 @@ void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
}
/*
- * evm_inode_init_security - initializes security.evm
+ * evm_inode_init_security - initializes security.evm HMAC value
*/
int evm_inode_init_security(struct inode *inode,
const struct xattr *lsm_xattr,
@@ -530,7 +530,8 @@ int evm_inode_init_security(struct inode *inode,
struct evm_xattr *xattr_data;
int rc;
- if (!evm_key_loaded() || !evm_protected_xattr(lsm_xattr->name))
+ if (!(evm_initialized & EVM_INIT_HMAC) ||
+ !evm_protected_xattr(lsm_xattr->name))
return 0;
xattr_data = kzalloc(sizeof(*xattr_data), GFP_NOFS);
--
2.26.2