Commit cc677088 authored by H. Peter Anvin's avatar H. Peter Anvin
Browse files

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: default avatarH. Peter Anvin <hpa@zytor.com>
parents 60f583d5 feff5dc4

drivers/firmware/efivars.c

+96 −34
Original line number Diff line number Diff line
@@ -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)

{
@@ -547,6 +585,11 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) 
	}



	spin_lock_irq(&efivars->lock);



	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,
@@ -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))
@@ -722,27 +764,17 @@ 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 > remaining_size)

		if (datasize > 65536)

			return -ENOSPC;

	}



	data = kmalloc(datasize, GFP_KERNEL);

	if (!data)
@@ -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);



	return d_alloc(parent, &q);

	d = d_alloc(parent, &q);

	if (d)

		return d;



	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,

tools/testing/selftests/efivarfs/efivarfs.sh

+59 −0
Original line number Diff line number Diff line
@@ -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

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