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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-13 11:29:00 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-13 11:29:00 +0900
commit4d7127dace8cf4b05eb7c8c8531fc204fbb195f4 (patch)
tree754111f5583a34b90babd521bcb68a3cad8a4912
parenta3920a6efa158b445b8a39080b463b9b29337425 (diff)
parent59b69ac2bad602d02904d310ee156e47e74d8109 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull TPM bugfixes from James Morris. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: tpm: Propagate error from tpm_transmit to fix a timeout hang driver/char/tpm: fix regression causesd by ppi
-rw-r--r--drivers/char/tpm/tpm.c24
-rw-r--r--drivers/char/tpm/tpm.h9
-rw-r--r--drivers/char/tpm/tpm_ppi.c18
3 files changed, 33 insertions, 18 deletions
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index f26afdb1a702..93211df52aab 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -1182,17 +1182,20 @@ ssize_t tpm_write(struct file *file, const char __user *buf,
size_t size, loff_t *off)
{
struct tpm_chip *chip = file->private_data;
- size_t in_size = size, out_size;
+ size_t in_size = size;
+ ssize_t out_size;
/* cannot perform a write until the read has cleared
- either via tpm_read or a user_read_timer timeout */
- while (atomic_read(&chip->data_pending) != 0)
- msleep(TPM_TIMEOUT);
-
- mutex_lock(&chip->buffer_mutex);
+ either via tpm_read or a user_read_timer timeout.
+ This also prevents splitted buffered writes from blocking here.
+ */
+ if (atomic_read(&chip->data_pending) != 0)
+ return -EBUSY;
if (in_size > TPM_BUFSIZE)
- in_size = TPM_BUFSIZE;
+ return -E2BIG;
+
+ mutex_lock(&chip->buffer_mutex);
if (copy_from_user
(chip->data_buffer, (void __user *) buf, in_size)) {
@@ -1202,6 +1205,10 @@ ssize_t tpm_write(struct file *file, const char __user *buf,
/* atomic tpm command send and result receive */
out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
+ if (out_size < 0) {
+ mutex_unlock(&chip->buffer_mutex);
+ return out_size;
+ }
atomic_set(&chip->data_pending, out_size);
mutex_unlock(&chip->buffer_mutex);
@@ -1259,6 +1266,7 @@ void tpm_remove_hardware(struct device *dev)
misc_deregister(&chip->vendor.miscdev);
sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
+ tpm_remove_ppi(&dev->kobj);
tpm_bios_log_teardown(chip->bios_dir);
/* write it this way to be explicit (chip->dev == dev) */
@@ -1476,7 +1484,7 @@ struct tpm_chip *tpm_register_hardware(struct device *dev,
goto put_device;
}
- if (sys_add_ppi(&dev->kobj)) {
+ if (tpm_add_ppi(&dev->kobj)) {
misc_deregister(&chip->vendor.miscdev);
goto put_device;
}
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 02c266aa2bf7..8ef7649a50aa 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -329,10 +329,15 @@ extern int wait_for_tpm_stat(struct tpm_chip *, u8, unsigned long,
wait_queue_head_t *);
#ifdef CONFIG_ACPI
-extern ssize_t sys_add_ppi(struct kobject *parent);
+extern int tpm_add_ppi(struct kobject *);
+extern void tpm_remove_ppi(struct kobject *);
#else
-static inline ssize_t sys_add_ppi(struct kobject *parent)
+static inline int tpm_add_ppi(struct kobject *parent)
{
return 0;
}
+
+static inline void tpm_remove_ppi(struct kobject *parent)
+{
+}
#endif
diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c
index f27b58cfae98..720ebcf29fdf 100644
--- a/drivers/char/tpm/tpm_ppi.c
+++ b/drivers/char/tpm/tpm_ppi.c
@@ -444,18 +444,20 @@ static struct attribute *ppi_attrs[] = {
&dev_attr_vs_operations.attr, NULL,
};
static struct attribute_group ppi_attr_grp = {
+ .name = "ppi",
.attrs = ppi_attrs
};
-ssize_t sys_add_ppi(struct kobject *parent)
+int tpm_add_ppi(struct kobject *parent)
{
- struct kobject *ppi;
- ppi = kobject_create_and_add("ppi", parent);
- if (sysfs_create_group(ppi, &ppi_attr_grp))
- return -EFAULT;
- else
- return 0;
+ return sysfs_create_group(parent, &ppi_attr_grp);
+}
+EXPORT_SYMBOL_GPL(tpm_add_ppi);
+
+void tpm_remove_ppi(struct kobject *parent)
+{
+ sysfs_remove_group(parent, &ppi_attr_grp);
}
-EXPORT_SYMBOL_GPL(sys_add_ppi);
+EXPORT_SYMBOL_GPL(tpm_remove_ppi);
MODULE_LICENSE("GPL");

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