Patch "fscrypto: add authorization check for setting encryption policy" has been added to the 4.7-stable tree
This is a note to let you know that I've just added the patch titled
fscrypto: add authorization check for setting encryption policy
to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fscrypto-add-authorization-check-for-setting-encryption-policy.patch
and it can be found in the queue-4.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
Quoted 1 line
From
163ae1c6ad6299b19e22b4a35d5ab24a89791a98Mon Sep 17 00:00:00 2001
From: Eric Biggers <[email protected]>
Date: Thu, 8 Sep 2016 10:57:08 -0700
Subject: fscrypto: add authorization check for setting encryption policy
From: Eric Biggers <[email protected]>
commit 163ae1c6ad6299b19e22b4a35d5ab24a89791a98 upstream.
On an ext4 or f2fs filesystem with file encryption supported, a user could set an encryption policy on any empty directory(*) to which they had readonly access. This is obviously problematic, since such a directory might be owned by another user and the new encryption policy would prevent that other user from creating files in their own directory (for example).
Fix this by requiring inode_owner_or_capable() permission to set an encryption policy. This means that either the caller must own the file, or the caller must have the capability CAP_FOWNER.
(*) Or also on any regular file, for f2fs v4.6 and later and ext4
v4.8-rc1 and later; a separate bug fix is coming for that.
--- fs/crypto/policy.c | 3 +++ 1 file changed, 3 insertions(+)
fs/crypto/policy.c +3 -0
@@ -95,6 +95,9 @@ static int create_encryption_context_froint fscrypt_process_policy (struct inode *inode,const struct fscrypt_policy *policy) { +if (!inode_owner_or_capable (inode)) +return -EACCES ; +if (policy->version !=0 )return -EINVAL ;
Patches currently in stable-queue which might be from [email protected] are
queue-4.7/fscrypto-add-authorization-check-for-setting-encryption-policy.patch queue-4.7/fscrypto-only-allow-setting-encryption-policy-on-directories.patch
Quoted 7 lines · On Mon, Sep 12, 2016 at 05:18:51PM +0200, [email protected] wrote:
This is a note to let you know that I've just added the patch titled
fscrypto: add authorization check for setting encryption policy
to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
For the 4.7 kernel, fs/ext4/crypto_policy.c needs to be patched as well since the buggy code was duplicated there. Here is the correct diff:
fs/crypto/policy.c +3 -0
@@ -95,6 +95,9 @@ static int create_encryption_context_from_policy(struct inode *inode,int fscrypt_process_policy (struct inode *inode,const struct fscrypt_policy *policy) { +if (!inode_owner_or_capable (inode)) +return -EACCES ; +if (policy->version !=0 )return -EINVAL ;
fs/ext4/crypto_policy.c +3 -0
@@ -102,6 +102,9 @@ static int ext4_create_encryption_context_from_policy(int ext4_process_policy (const struct ext4_encryption_policy *policy,struct inode *inode) { +if (!inode_owner_or_capable (inode)) +return -EACCES ; +if (policy->version !=0 )return -EINVAL ;
Signature · 1 line
2.8.0.rc3.226.g39d4020
Quoted 11 lines · Eric Biggers
Quoted 7 lines · On Mon, Sep 12, 2016 at 05:18:51PM +0200, [email protected] wrote:
This is a note to let you know that I've just added the patch titled
fscrypto: add authorization check for setting encryption policy
to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summaryFor the 4.7 kernel,
fs/ext4/crypto_policy.cneeds to be patched as well since the buggy code was duplicated there. Here is the correct diff:
Quoted 32 lines
fs/crypto/policy.c +3
-0@@ -95,6 +95,9 @@ static int create_encryption_context_from_policy(struct inode *inode,int fscrypt_process_policy (struct inode *inode,const struct fscrypt_policy *policy) { +if (!inode_owner_or_capable (inode)) +return -EACCES ; +if (policy->version !=0 )return -EINVAL ;fs/ext4/crypto_policy.c +3
-0@@ -102,6 +102,9 @@ static int ext4_create_encryption_context_from_policy(int ext4_process_policy (const struct ext4_encryption_policy *policy,struct inode *inode) { +if (!inode_owner_or_capable (inode)) +return -EACCES ; +if (policy->version !=0 )return -EINVAL ;Signature · 1 line
2.8.0.rc3.226.g39d4020
Greg KH
maintainerQuoted 31 lines · Eric Biggers
Quoted 7 lines · On Mon, Sep 12, 2016 at 05:18:51PM +0200, [email protected] wrote:
This is a note to let you know that I've just added the patch titled
fscrypto: add authorization check for setting encryption policy
to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summaryFor the 4.7 kernel,
fs/ext4/crypto_policy.cneeds to be patched as well since the buggy code was duplicated there. Here is the correct diff:fs/crypto/policy.c +3
-0@@ -95,6 +95,9 @@ static int create_encryption_context_from_policy(struct inode *inode,int fscrypt_process_policy (struct inode *inode,const struct fscrypt_policy *policy) { +if (!inode_owner_or_capable (inode)) +return -EACCES ; +if (policy->version !=0 )return -EINVAL ;fs/ext4/crypto_policy.c +0
-0
fs/ext4/crypto_policy.c static int ext4_create_encryption_context_from_policy( · line 110
Quoted 9 lines
fs/ext4/crypto_policy.c +3
-0@@ -102,6 +102,9 @@ static int ext4_create_encryption_context_from_policy(int ext4_process_policy (const struct ext4_encryption_policy *policy,struct inode *inode) { +if (!inode_owner_or_capable (inode)) +return -EACCES ; +if (policy->version !=0 )return -EINVAL ;
Thanks for this, now updated.
greg k-h