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authorH. Peter Anvin <hpa@zytor.com>2013-03-07 13:25:10 -0800
committerH. Peter Anvin <hpa@zytor.com>2013-03-07 13:25:59 -0800
commitcc67708891319dbdc9f29c04154833a67d23212c (patch)
treeab89e2109995a08471b161b9866c1f8898af7e2f
parent60f583d56aa515b896a9d94f860f52640c1e8a75 (diff)
parentfeff5dc4f98330d8152b521acc2e18c16712e6c8 (diff)
downloadlinux-stericsson-cc67708891319dbdc9f29c04154833a67d23212c.tar.gz
Merge tag 'efi-for-3.9-rc2' into x86/urgent
EFI changes for v3.9-rc2, * Make the EFI variable code more paranoid about running out of space in NVRAM, since this is the root cause of the recent issue where machines refuse to boot - from Matthew Garrett. * Some efivarfs patches that fix regressions introduced in v3.9-rc1. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
-rw-r--r--drivers/firmware/efivars.c130
-rw-r--r--tools/testing/selftests/efivarfs/efivarfs.sh59
2 files changed, 155 insertions, 34 deletions
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 7320bf891706..bea32d1ef7d5 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -426,6 +426,44 @@ get_var_data(struct efivars *efivars, struct efi_variable *var)
return status;
}
+static efi_status_t
+check_var_size_locked(struct efivars *efivars, u32 attributes,
+ unsigned long size)
+{
+ u64 storage_size, remaining_size, max_size;
+ efi_status_t status;
+ const struct efivar_operations *fops = efivars->ops;
+
+ if (!efivars->ops->query_variable_info)
+ return EFI_UNSUPPORTED;
+
+ status = fops->query_variable_info(attributes, &storage_size,
+ &remaining_size, &max_size);
+
+ if (status != EFI_SUCCESS)
+ return status;
+
+ if (!storage_size || size > remaining_size || size > max_size ||
+ (remaining_size - size) < (storage_size / 2))
+ return EFI_OUT_OF_RESOURCES;
+
+ return status;
+}
+
+
+static efi_status_t
+check_var_size(struct efivars *efivars, u32 attributes, unsigned long size)
+{
+ efi_status_t status;
+ unsigned long flags;
+
+ spin_lock_irqsave(&efivars->lock, flags);
+ status = check_var_size_locked(efivars, attributes, size);
+ spin_unlock_irqrestore(&efivars->lock, flags);
+
+ return status;
+}
+
static ssize_t
efivar_guid_read(struct efivar_entry *entry, char *buf)
{
@@ -547,11 +585,16 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
}
spin_lock_irq(&efivars->lock);
- status = efivars->ops->set_variable(new_var->VariableName,
- &new_var->VendorGuid,
- new_var->Attributes,
- new_var->DataSize,
- new_var->Data);
+
+ status = check_var_size_locked(efivars, new_var->Attributes,
+ new_var->DataSize + utf16_strsize(new_var->VariableName, 1024));
+
+ if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED)
+ status = efivars->ops->set_variable(new_var->VariableName,
+ &new_var->VendorGuid,
+ new_var->Attributes,
+ new_var->DataSize,
+ new_var->Data);
spin_unlock_irq(&efivars->lock);
@@ -702,8 +745,7 @@ static ssize_t efivarfs_file_write(struct file *file,
u32 attributes;
struct inode *inode = file->f_mapping->host;
unsigned long datasize = count - sizeof(attributes);
- unsigned long newdatasize;
- u64 storage_size, remaining_size, max_size;
+ unsigned long newdatasize, varsize;
ssize_t bytes = 0;
if (count < sizeof(attributes))
@@ -722,28 +764,18 @@ static ssize_t efivarfs_file_write(struct file *file,
* amounts of memory. Pick a default size of 64K if
* QueryVariableInfo() isn't supported by the firmware.
*/
- spin_lock_irq(&efivars->lock);
-
- if (!efivars->ops->query_variable_info)
- status = EFI_UNSUPPORTED;
- else {
- const struct efivar_operations *fops = efivars->ops;
- status = fops->query_variable_info(attributes, &storage_size,
- &remaining_size, &max_size);
- }
- spin_unlock_irq(&efivars->lock);
+ varsize = datasize + utf16_strsize(var->var.VariableName, 1024);
+ status = check_var_size(efivars, attributes, varsize);
if (status != EFI_SUCCESS) {
if (status != EFI_UNSUPPORTED)
return efi_status_to_err(status);
- remaining_size = 65536;
+ if (datasize > 65536)
+ return -ENOSPC;
}
- if (datasize > remaining_size)
- return -ENOSPC;
-
data = kmalloc(datasize, GFP_KERNEL);
if (!data)
return -ENOMEM;
@@ -765,6 +797,19 @@ static ssize_t efivarfs_file_write(struct file *file,
*/
spin_lock_irq(&efivars->lock);
+ /*
+ * Ensure that the available space hasn't shrunk below the safe level
+ */
+
+ status = check_var_size_locked(efivars, attributes, varsize);
+
+ if (status != EFI_SUCCESS && status != EFI_UNSUPPORTED) {
+ spin_unlock_irq(&efivars->lock);
+ kfree(data);
+
+ return efi_status_to_err(status);
+ }
+
status = efivars->ops->set_variable(var->var.VariableName,
&var->var.VendorGuid,
attributes, datasize,
@@ -929,8 +974,8 @@ static bool efivarfs_valid_name(const char *str, int len)
if (len < GUID_LEN + 2)
return false;
- /* GUID should be right after the first '-' */
- if (s - 1 != strchr(str, '-'))
+ /* GUID must be preceded by a '-' */
+ if (*(s - 1) != '-')
return false;
/*
@@ -1118,15 +1163,22 @@ static struct dentry_operations efivarfs_d_ops = {
static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name)
{
+ struct dentry *d;
struct qstr q;
+ int err;
q.name = name;
q.len = strlen(name);
- if (efivarfs_d_hash(NULL, NULL, &q))
- return NULL;
+ err = efivarfs_d_hash(NULL, NULL, &q);
+ if (err)
+ return ERR_PTR(err);
+
+ d = d_alloc(parent, &q);
+ if (d)
+ return d;
- return d_alloc(parent, &q);
+ return ERR_PTR(-ENOMEM);
}
static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
@@ -1136,6 +1188,7 @@ static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
struct efivar_entry *entry, *n;
struct efivars *efivars = &__efivars;
char *name;
+ int err = -ENOMEM;
efivarfs_sb = sb;
@@ -1186,8 +1239,10 @@ static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
goto fail_name;
dentry = efivarfs_alloc_dentry(root, name);
- if (!dentry)
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
goto fail_inode;
+ }
/* copied by the above to local storage in the dentry. */
kfree(name);
@@ -1214,7 +1269,7 @@ fail_inode:
fail_name:
kfree(name);
fail:
- return -ENOMEM;
+ return err;
}
static struct dentry *efivarfs_mount(struct file_system_type *fs_type,
@@ -1345,7 +1400,6 @@ static int efi_pstore_write(enum pstore_type_id type,
efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
struct efivars *efivars = psi->data;
int i, ret = 0;
- u64 storage_space, remaining_space, max_variable_size;
efi_status_t status = EFI_NOT_FOUND;
unsigned long flags;
@@ -1365,11 +1419,11 @@ static int efi_pstore_write(enum pstore_type_id type,
* size: a size of logging data
* DUMP_NAME_LEN * 2: a maximum size of variable name
*/
- status = efivars->ops->query_variable_info(PSTORE_EFI_ATTRIBUTES,
- &storage_space,
- &remaining_space,
- &max_variable_size);
- if (status || remaining_space < size + DUMP_NAME_LEN * 2) {
+
+ status = check_var_size_locked(efivars, PSTORE_EFI_ATTRIBUTES,
+ size + DUMP_NAME_LEN * 2);
+
+ if (status) {
spin_unlock_irqrestore(&efivars->lock, flags);
*id = part;
return -ENOSPC;
@@ -1544,6 +1598,14 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
return -EINVAL;
}
+ status = check_var_size_locked(efivars, new_var->Attributes,
+ new_var->DataSize + utf16_strsize(new_var->VariableName, 1024));
+
+ if (status && status != EFI_UNSUPPORTED) {
+ spin_unlock_irq(&efivars->lock);
+ return efi_status_to_err(status);
+ }
+
/* now *really* create the variable via EFI */
status = efivars->ops->set_variable(new_var->VariableName,
&new_var->VendorGuid,
diff --git a/tools/testing/selftests/efivarfs/efivarfs.sh b/tools/testing/selftests/efivarfs/efivarfs.sh
index 880cdd5dc63f..77edcdcc016b 100644
--- a/tools/testing/selftests/efivarfs/efivarfs.sh
+++ b/tools/testing/selftests/efivarfs/efivarfs.sh
@@ -125,6 +125,63 @@ test_open_unlink()
./open-unlink $file
}
+# test that we can create a range of filenames
+test_valid_filenames()
+{
+ local attrs='\x07\x00\x00\x00'
+ local ret=0
+
+ local file_list="abc dump-type0-11-1-1362436005 1234 -"
+ for f in $file_list; do
+ local file=$efivarfs_mount/$f-$test_guid
+
+ printf "$attrs\x00" > $file
+
+ if [ ! -e $file ]; then
+ echo "$file could not be created" >&2
+ ret=1
+ else
+ rm $file
+ fi
+ done
+
+ exit $ret
+}
+
+test_invalid_filenames()
+{
+ local attrs='\x07\x00\x00\x00'
+ local ret=0
+
+ local file_list="
+ -1234-1234-1234-123456789abc
+ foo
+ foo-bar
+ -foo-
+ foo-barbazba-foob-foob-foob-foobarbazfoo
+ foo-------------------------------------
+ -12345678-1234-1234-1234-123456789abc
+ a-12345678=1234-1234-1234-123456789abc
+ a-12345678-1234=1234-1234-123456789abc
+ a-12345678-1234-1234=1234-123456789abc
+ a-12345678-1234-1234-1234=123456789abc
+ 1112345678-1234-1234-1234-123456789abc"
+
+ for f in $file_list; do
+ local file=$efivarfs_mount/$f
+
+ printf "$attrs\x00" 2>/dev/null > $file
+
+ if [ -e $file ]; then
+ echo "Creating $file should have failed" >&2
+ rm $file
+ ret=1
+ fi
+ done
+
+ exit $ret
+}
+
check_prereqs
rc=0
@@ -135,5 +192,7 @@ run_test test_create_read
run_test test_delete
run_test test_zero_size_delete
run_test test_open_unlink
+run_test test_valid_filenames
+run_test test_invalid_filenames
exit $rc