* [f2fs-dev] [PATCH 4.9 1/2] fscrypto: move ioctl processing more fully into common code
2020-10-31 23:11 [f2fs-dev] [PATCH 4.9 0/2] backport some more fscrypt fixes to 4.9 Eric Biggers
@ 2020-10-31 23:11 ` Eric Biggers
2020-10-31 23:11 ` [f2fs-dev] [PATCH 4.9 2/2] fscrypt: use EEXIST when file already uses different policy Eric Biggers
2020-11-01 10:32 ` [f2fs-dev] [PATCH 4.9 0/2] backport some more fscrypt fixes to 4.9 Greg KH
2 siblings, 0 replies; 4+ messages in thread
From: Eric Biggers @ 2020-10-31 23:11 UTC (permalink / raw)
To: stable; +Cc: linux-fscrypt, linux-ext4, Theodore Ts'o, linux-f2fs-devel
From: Eric Biggers <ebiggers@google.com>
commit db717d8e26c2d1b0dba3e08668a1e6a7f665adde upstream.
Multiple bugs were recently fixed in the "set encryption policy" ioctl.
To make it clear that fscrypt_process_policy() and fscrypt_get_policy()
implement ioctls and therefore their implementations must take standard
security and correctness precautions, rename them to
fscrypt_ioctl_set_policy() and fscrypt_ioctl_get_policy(). Make the
latter take in a struct file * to make it consistent with the former.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
fs/crypto/policy.c | 34 +++++++++++++++++++++-------------
fs/ext4/ext4.h | 4 ++--
fs/ext4/ioctl.c | 34 +++++-----------------------------
fs/f2fs/f2fs.h | 4 ++--
fs/f2fs/file.c | 19 ++-----------------
include/linux/fscrypto.h | 12 ++++++------
6 files changed, 38 insertions(+), 69 deletions(-)
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index 51f4463718e84..a89e50331deb6 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -93,16 +93,19 @@ static int create_encryption_context_from_policy(struct inode *inode,
return inode->i_sb->s_cop->set_context(inode, &ctx, sizeof(ctx), NULL);
}
-int fscrypt_process_policy(struct file *filp,
- const struct fscrypt_policy *policy)
+int fscrypt_ioctl_set_policy(struct file *filp, const void __user *arg)
{
+ struct fscrypt_policy policy;
struct inode *inode = file_inode(filp);
int ret;
+ if (copy_from_user(&policy, arg, sizeof(policy)))
+ return -EFAULT;
+
if (!inode_owner_or_capable(inode))
return -EACCES;
- if (policy->version != 0)
+ if (policy.version != 0)
return -EINVAL;
ret = mnt_want_write_file(filp);
@@ -122,9 +125,9 @@ int fscrypt_process_policy(struct file *filp,
ret = -ENOTEMPTY;
else
ret = create_encryption_context_from_policy(inode,
- policy);
+ &policy);
} else if (!is_encryption_context_consistent_with_policy(inode,
- policy)) {
+ &policy)) {
printk(KERN_WARNING
"%s: Policy inconsistent with encryption context\n",
__func__);
@@ -136,11 +139,13 @@ int fscrypt_process_policy(struct file *filp,
mnt_drop_write_file(filp);
return ret;
}
-EXPORT_SYMBOL(fscrypt_process_policy);
+EXPORT_SYMBOL(fscrypt_ioctl_set_policy);
-int fscrypt_get_policy(struct inode *inode, struct fscrypt_policy *policy)
+int fscrypt_ioctl_get_policy(struct file *filp, void __user *arg)
{
+ struct inode *inode = file_inode(filp);
struct fscrypt_context ctx;
+ struct fscrypt_policy policy;
int res;
if (!inode->i_sb->s_cop->get_context ||
@@ -153,15 +158,18 @@ int fscrypt_get_policy(struct inode *inode, struct fscrypt_policy *policy)
if (ctx.format != FS_ENCRYPTION_CONTEXT_FORMAT_V1)
return -EINVAL;
- policy->version = 0;
- policy->contents_encryption_mode = ctx.contents_encryption_mode;
- policy->filenames_encryption_mode = ctx.filenames_encryption_mode;
- policy->flags = ctx.flags;
- memcpy(&policy->master_key_descriptor, ctx.master_key_descriptor,
+ policy.version = 0;
+ policy.contents_encryption_mode = ctx.contents_encryption_mode;
+ policy.filenames_encryption_mode = ctx.filenames_encryption_mode;
+ policy.flags = ctx.flags;
+ memcpy(policy.master_key_descriptor, ctx.master_key_descriptor,
FS_KEY_DESCRIPTOR_SIZE);
+
+ if (copy_to_user(arg, &policy, sizeof(policy)))
+ return -EFAULT;
return 0;
}
-EXPORT_SYMBOL(fscrypt_get_policy);
+EXPORT_SYMBOL(fscrypt_ioctl_get_policy);
/**
* fscrypt_has_permitted_context() - is a file's encryption policy permitted
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index b41ac328c3964..360954196e2f3 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2354,8 +2354,8 @@ static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
#define fscrypt_pullback_bio_page fscrypt_notsupp_pullback_bio_page
#define fscrypt_restore_control_page fscrypt_notsupp_restore_control_page
#define fscrypt_zeroout_range fscrypt_notsupp_zeroout_range
-#define fscrypt_process_policy fscrypt_notsupp_process_policy
-#define fscrypt_get_policy fscrypt_notsupp_get_policy
+#define fscrypt_ioctl_set_policy fscrypt_notsupp_ioctl_set_policy
+#define fscrypt_ioctl_get_policy fscrypt_notsupp_ioctl_get_policy
#define fscrypt_has_permitted_context fscrypt_notsupp_has_permitted_context
#define fscrypt_inherit_context fscrypt_notsupp_inherit_context
#define fscrypt_get_encryption_info fscrypt_notsupp_get_encryption_info
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index eada4172c4ef1..2016f5a5d3cf1 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -774,22 +774,12 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
}
case EXT4_IOC_PRECACHE_EXTENTS:
return ext4_ext_precache(inode);
- case EXT4_IOC_SET_ENCRYPTION_POLICY: {
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
- struct fscrypt_policy policy;
+ case EXT4_IOC_SET_ENCRYPTION_POLICY:
if (!ext4_has_feature_encrypt(sb))
return -EOPNOTSUPP;
+ return fscrypt_ioctl_set_policy(filp, (const void __user *)arg);
- if (copy_from_user(&policy,
- (struct fscrypt_policy __user *)arg,
- sizeof(policy)))
- return -EFAULT;
- return fscrypt_process_policy(filp, &policy);
-#else
- return -EOPNOTSUPP;
-#endif
- }
case EXT4_IOC_GET_ENCRYPTION_PWSALT: {
int err, err2;
struct ext4_sb_info *sbi = EXT4_SB(sb);
@@ -826,23 +816,9 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return -EFAULT;
return 0;
}
- case EXT4_IOC_GET_ENCRYPTION_POLICY: {
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
- struct fscrypt_policy policy;
- int err = 0;
-
- if (!ext4_encrypted_inode(inode))
- return -ENOENT;
- err = fscrypt_get_policy(inode, &policy);
- if (err)
- return err;
- if (copy_to_user((void __user *)arg, &policy, sizeof(policy)))
- return -EFAULT;
- return 0;
-#else
- return -EOPNOTSUPP;
-#endif
- }
+ case EXT4_IOC_GET_ENCRYPTION_POLICY:
+ return fscrypt_ioctl_get_policy(filp, (void __user *)arg);
+
case EXT4_IOC_FSGETXATTR:
{
struct fsxattr fa;
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b16ab4187234d..7016a59142e3e 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2513,8 +2513,8 @@ static inline bool f2fs_may_encrypt(struct inode *inode)
#define fscrypt_pullback_bio_page fscrypt_notsupp_pullback_bio_page
#define fscrypt_restore_control_page fscrypt_notsupp_restore_control_page
#define fscrypt_zeroout_range fscrypt_notsupp_zeroout_range
-#define fscrypt_process_policy fscrypt_notsupp_process_policy
-#define fscrypt_get_policy fscrypt_notsupp_get_policy
+#define fscrypt_ioctl_set_policy fscrypt_notsupp_ioctl_set_policy
+#define fscrypt_ioctl_get_policy fscrypt_notsupp_ioctl_get_policy
#define fscrypt_has_permitted_context fscrypt_notsupp_has_permitted_context
#define fscrypt_inherit_context fscrypt_notsupp_inherit_context
#define fscrypt_get_encryption_info fscrypt_notsupp_get_encryption_info
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index e3c438c8b8ce0..0bedcd70b51f4 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1774,31 +1774,16 @@ static bool uuid_is_nonzero(__u8 u[16])
static int f2fs_ioc_set_encryption_policy(struct file *filp, unsigned long arg)
{
- struct fscrypt_policy policy;
struct inode *inode = file_inode(filp);
- if (copy_from_user(&policy, (struct fscrypt_policy __user *)arg,
- sizeof(policy)))
- return -EFAULT;
-
f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
- return fscrypt_process_policy(filp, &policy);
+ return fscrypt_ioctl_set_policy(filp, (const void __user *)arg);
}
static int f2fs_ioc_get_encryption_policy(struct file *filp, unsigned long arg)
{
- struct fscrypt_policy policy;
- struct inode *inode = file_inode(filp);
- int err;
-
- err = fscrypt_get_policy(inode, &policy);
- if (err)
- return err;
-
- if (copy_to_user((struct fscrypt_policy __user *)arg, &policy, sizeof(policy)))
- return -EFAULT;
- return 0;
+ return fscrypt_ioctl_get_policy(filp, (void __user *)arg);
}
static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg)
diff --git a/include/linux/fscrypto.h b/include/linux/fscrypto.h
index f6dfc2950f764..3b1f17dbf92d9 100644
--- a/include/linux/fscrypto.h
+++ b/include/linux/fscrypto.h
@@ -249,8 +249,8 @@ extern void fscrypt_restore_control_page(struct page *);
extern int fscrypt_zeroout_range(struct inode *, pgoff_t, sector_t,
unsigned int);
/* policy.c */
-extern int fscrypt_process_policy(struct file *, const struct fscrypt_policy *);
-extern int fscrypt_get_policy(struct inode *, struct fscrypt_policy *);
+extern int fscrypt_ioctl_set_policy(struct file *, const void __user *);
+extern int fscrypt_ioctl_get_policy(struct file *, void __user *);
extern int fscrypt_has_permitted_context(struct inode *, struct inode *);
extern int fscrypt_inherit_context(struct inode *, struct inode *,
void *, bool);
@@ -318,14 +318,14 @@ static inline int fscrypt_notsupp_zeroout_range(struct inode *i, pgoff_t p,
}
/* policy.c */
-static inline int fscrypt_notsupp_process_policy(struct file *f,
- const struct fscrypt_policy *p)
+static inline int fscrypt_notsupp_ioctl_set_policy(struct file *f,
+ const void __user *arg)
{
return -EOPNOTSUPP;
}
-static inline int fscrypt_notsupp_get_policy(struct inode *i,
- struct fscrypt_policy *p)
+static inline int fscrypt_notsupp_ioctl_get_policy(struct file *f,
+ void __user *arg)
{
return -EOPNOTSUPP;
}
--
2.29.1
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