| Message ID | 20230831104136.903180-14-roberto.sassu@huaweicloud.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | security: Move IMA and EVM to the LSM infrastructure | expand |
On 8/31/2023 3:41 AM, Roberto Sassu wrote: > From: Roberto Sassu <roberto.sassu@huawei.com> > > In preparation for moving IMA and EVM to the LSM infrastructure, introduce > the inode_post_removexattr hook. This applies to all new LSM hooks: Would you please include some explanation of how an LSM would use this hook? You might start with a description of how it is used in IMA/EVM, and why that could be generally useful. > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> > --- > fs/xattr.c | 9 +++++---- > include/linux/lsm_hook_defs.h | 2 ++ > include/linux/security.h | 5 +++++ > security/security.c | 14 ++++++++++++++ > 4 files changed, 26 insertions(+), 4 deletions(-) > > diff --git a/fs/xattr.c b/fs/xattr.c > index e7bbb7f57557..4a0280295686 100644 > --- a/fs/xattr.c > +++ b/fs/xattr.c > @@ -552,11 +552,12 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, > goto out; > > error = __vfs_removexattr(idmap, dentry, name); > + if (error) > + goto out; > > - if (!error) { > - fsnotify_xattr(dentry); > - evm_inode_post_removexattr(dentry, name); > - } > + fsnotify_xattr(dentry); > + security_inode_post_removexattr(dentry, name); > + evm_inode_post_removexattr(dentry, name); > > out: > return error; > diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h > index 995d30336cfa..1153e7163b8b 100644 > --- a/include/linux/lsm_hook_defs.h > +++ b/include/linux/lsm_hook_defs.h > @@ -148,6 +148,8 @@ LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name) > LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry) > LSM_HOOK(int, 0, inode_removexattr, struct mnt_idmap *idmap, > struct dentry *dentry, const char *name) > +LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry, > + const char *name) > LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap, > struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) > LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, > diff --git a/include/linux/security.h b/include/linux/security.h > index 820899db5276..665bba3e0081 100644 > --- a/include/linux/security.h > +++ b/include/linux/security.h > @@ -374,6 +374,7 @@ int security_inode_getxattr(struct dentry *dentry, const char *name); > int security_inode_listxattr(struct dentry *dentry); > int security_inode_removexattr(struct mnt_idmap *idmap, > struct dentry *dentry, const char *name); > +void security_inode_post_removexattr(struct dentry *dentry, const char *name); > int security_inode_need_killpriv(struct dentry *dentry); > int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry); > int security_inode_getsecurity(struct mnt_idmap *idmap, > @@ -919,6 +920,10 @@ static inline int security_inode_removexattr(struct mnt_idmap *idmap, > return cap_inode_removexattr(idmap, dentry, name); > } > > +static inline void security_inode_post_removexattr(struct dentry *dentry, > + const char *name) > +{ } > + > static inline int security_inode_need_killpriv(struct dentry *dentry) > { > return cap_inode_need_killpriv(dentry); > diff --git a/security/security.c b/security/security.c > index 764a6f28b3b9..3947159ba5e9 100644 > --- a/security/security.c > +++ b/security/security.c > @@ -2354,6 +2354,20 @@ int security_inode_removexattr(struct mnt_idmap *idmap, > return evm_inode_removexattr(idmap, dentry, name); > } > > +/** > + * security_inode_post_removexattr() - Update the inode after a removexattr op > + * @dentry: file > + * @name: xattr name > + * > + * Update the inode after a successful removexattr operation. > + */ > +void security_inode_post_removexattr(struct dentry *dentry, const char *name) > +{ > + if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) > + return; > + call_void_hook(inode_post_removexattr, dentry, name); > +} > + > /** > * security_inode_need_killpriv() - Check if security_inode_killpriv() required > * @dentry: associated dentry
On Thu Aug 31, 2023 at 1:41 PM EEST, Roberto Sassu wrote: > From: Roberto Sassu <roberto.sassu@huawei.com> > > In preparation for moving IMA and EVM to the LSM infrastructure, introduce > the inode_post_removexattr hook. > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> > --- > fs/xattr.c | 9 +++++---- > include/linux/lsm_hook_defs.h | 2 ++ > include/linux/security.h | 5 +++++ > security/security.c | 14 ++++++++++++++ > 4 files changed, 26 insertions(+), 4 deletions(-) > > diff --git a/fs/xattr.c b/fs/xattr.c > index e7bbb7f57557..4a0280295686 100644 > --- a/fs/xattr.c > +++ b/fs/xattr.c > @@ -552,11 +552,12 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, > goto out; > > error = __vfs_removexattr(idmap, dentry, name); > + if (error) > + goto out; > > - if (!error) { > - fsnotify_xattr(dentry); > - evm_inode_post_removexattr(dentry, name); > - } > + fsnotify_xattr(dentry); > + security_inode_post_removexattr(dentry, name); > + evm_inode_post_removexattr(dentry, name); > > out: > return error; > diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h > index 995d30336cfa..1153e7163b8b 100644 > --- a/include/linux/lsm_hook_defs.h > +++ b/include/linux/lsm_hook_defs.h > @@ -148,6 +148,8 @@ LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name) > LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry) > LSM_HOOK(int, 0, inode_removexattr, struct mnt_idmap *idmap, > struct dentry *dentry, const char *name) > +LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry, > + const char *name) > LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap, > struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) > LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, > diff --git a/include/linux/security.h b/include/linux/security.h > index 820899db5276..665bba3e0081 100644 > --- a/include/linux/security.h > +++ b/include/linux/security.h > @@ -374,6 +374,7 @@ int security_inode_getxattr(struct dentry *dentry, const char *name); > int security_inode_listxattr(struct dentry *dentry); > int security_inode_removexattr(struct mnt_idmap *idmap, > struct dentry *dentry, const char *name); > +void security_inode_post_removexattr(struct dentry *dentry, const char *name); > int security_inode_need_killpriv(struct dentry *dentry); > int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry); > int security_inode_getsecurity(struct mnt_idmap *idmap, > @@ -919,6 +920,10 @@ static inline int security_inode_removexattr(struct mnt_idmap *idmap, > return cap_inode_removexattr(idmap, dentry, name); > } > > +static inline void security_inode_post_removexattr(struct dentry *dentry, > + const char *name) > +{ } static inline void security_inode_post_removexattr(struct dentry *dentry, const char *name) { } > + > static inline int security_inode_need_killpriv(struct dentry *dentry) > { > return cap_inode_need_killpriv(dentry); > diff --git a/security/security.c b/security/security.c > index 764a6f28b3b9..3947159ba5e9 100644 > --- a/security/security.c > +++ b/security/security.c > @@ -2354,6 +2354,20 @@ int security_inode_removexattr(struct mnt_idmap *idmap, > return evm_inode_removexattr(idmap, dentry, name); > } > > +/** > + * security_inode_post_removexattr() - Update the inode after a removexattr op > + * @dentry: file > + * @name: xattr name > + * > + * Update the inode after a successful removexattr operation. > + */ > +void security_inode_post_removexattr(struct dentry *dentry, const char *name) > +{ > + if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) > + return; > + call_void_hook(inode_post_removexattr, dentry, name); > +} > + > /** > * security_inode_need_killpriv() - Check if security_inode_killpriv() required > * @dentry: associated dentry > -- > 2.34.1 These odd splits are everywhere in the patch set. Just (nit)picking some. It is huge patch set so I don't really get for addign extra lines for no good reason. BR, Jarkko
On Tue, 2023-09-05 at 00:11 +0300, Jarkko Sakkinen wrote: > On Thu Aug 31, 2023 at 1:41 PM EEST, Roberto Sassu wrote: > > From: Roberto Sassu <roberto.sassu@huawei.com> > > > > In preparation for moving IMA and EVM to the LSM infrastructure, introduce > > the inode_post_removexattr hook. > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> > > --- > > fs/xattr.c | 9 +++++---- > > include/linux/lsm_hook_defs.h | 2 ++ > > include/linux/security.h | 5 +++++ > > security/security.c | 14 ++++++++++++++ > > 4 files changed, 26 insertions(+), 4 deletions(-) > > > > diff --git a/fs/xattr.c b/fs/xattr.c > > index e7bbb7f57557..4a0280295686 100644 > > --- a/fs/xattr.c > > +++ b/fs/xattr.c > > @@ -552,11 +552,12 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, > > goto out; > > > > error = __vfs_removexattr(idmap, dentry, name); > > + if (error) > > + goto out; > > > > - if (!error) { > > - fsnotify_xattr(dentry); > > - evm_inode_post_removexattr(dentry, name); > > - } > > + fsnotify_xattr(dentry); > > + security_inode_post_removexattr(dentry, name); > > + evm_inode_post_removexattr(dentry, name); > > > > out: > > return error; > > diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h > > index 995d30336cfa..1153e7163b8b 100644 > > --- a/include/linux/lsm_hook_defs.h > > +++ b/include/linux/lsm_hook_defs.h > > @@ -148,6 +148,8 @@ LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name) > > LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry) > > LSM_HOOK(int, 0, inode_removexattr, struct mnt_idmap *idmap, > > struct dentry *dentry, const char *name) > > +LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry, > > + const char *name) > > LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap, > > struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) > > LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, > > diff --git a/include/linux/security.h b/include/linux/security.h > > index 820899db5276..665bba3e0081 100644 > > --- a/include/linux/security.h > > +++ b/include/linux/security.h > > @@ -374,6 +374,7 @@ int security_inode_getxattr(struct dentry *dentry, const char *name); > > int security_inode_listxattr(struct dentry *dentry); > > int security_inode_removexattr(struct mnt_idmap *idmap, > > struct dentry *dentry, const char *name); > > +void security_inode_post_removexattr(struct dentry *dentry, const char *name); > > int security_inode_need_killpriv(struct dentry *dentry); > > int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry); > > int security_inode_getsecurity(struct mnt_idmap *idmap, > > @@ -919,6 +920,10 @@ static inline int security_inode_removexattr(struct mnt_idmap *idmap, > > return cap_inode_removexattr(idmap, dentry, name); > > } > > > > +static inline void security_inode_post_removexattr(struct dentry *dentry, > > + const char *name) > > +{ } > > static inline void security_inode_post_removexattr(struct dentry *dentry, const char *name) > { > } > > > + > > static inline int security_inode_need_killpriv(struct dentry *dentry) > > { > > return cap_inode_need_killpriv(dentry); > > diff --git a/security/security.c b/security/security.c > > index 764a6f28b3b9..3947159ba5e9 100644 > > --- a/security/security.c > > +++ b/security/security.c > > @@ -2354,6 +2354,20 @@ int security_inode_removexattr(struct mnt_idmap *idmap, > > return evm_inode_removexattr(idmap, dentry, name); > > } > > > > +/** > > + * security_inode_post_removexattr() - Update the inode after a removexattr op > > + * @dentry: file > > + * @name: xattr name > > + * > > + * Update the inode after a successful removexattr operation. > > + */ > > +void security_inode_post_removexattr(struct dentry *dentry, const char *name) > > +{ > > + if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) > > + return; > > + call_void_hook(inode_post_removexattr, dentry, name); > > +} > > + > > /** > > * security_inode_need_killpriv() - Check if security_inode_killpriv() required > > * @dentry: associated dentry > > -- > > 2.34.1 > > > These odd splits are everywhere in the patch set. Just (nit)picking some. > > It is huge patch set so I don't really get for addign extra lines for no > good reason. Thanks for the review, Jarkko. I don't know... to be honest I still prefer to stay within 80 characters. Roberto
On Tue, 2023-09-05 at 08:51 +0200, Roberto Sassu wrote: > On Tue, 2023-09-05 at 00:11 +0300, Jarkko Sakkinen wrote: > > On Thu Aug 31, 2023 at 1:41 PM EEST, Roberto Sassu wrote: > > > From: Roberto Sassu <roberto.sassu@huawei.com> > > > > > > In preparation for moving IMA and EVM to the LSM infrastructure, introduce > > > the inode_post_removexattr hook. > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > > Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> > > > --- > > > fs/xattr.c | 9 +++++---- > > > include/linux/lsm_hook_defs.h | 2 ++ > > > include/linux/security.h | 5 +++++ > > > security/security.c | 14 ++++++++++++++ > > > 4 files changed, 26 insertions(+), 4 deletions(-) > > > > > > diff --git a/fs/xattr.c b/fs/xattr.c > > > index e7bbb7f57557..4a0280295686 100644 > > > --- a/fs/xattr.c > > > +++ b/fs/xattr.c > > > @@ -552,11 +552,12 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, > > > goto out; > > > > > > error = __vfs_removexattr(idmap, dentry, name); > > > + if (error) > > > + goto out; > > > > > > - if (!error) { > > > - fsnotify_xattr(dentry); > > > - evm_inode_post_removexattr(dentry, name); > > > - } > > > + fsnotify_xattr(dentry); > > > + security_inode_post_removexattr(dentry, name); > > > + evm_inode_post_removexattr(dentry, name); > > > > > > out: > > > return error; > > > diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h > > > index 995d30336cfa..1153e7163b8b 100644 > > > --- a/include/linux/lsm_hook_defs.h > > > +++ b/include/linux/lsm_hook_defs.h > > > @@ -148,6 +148,8 @@ LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name) > > > LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry) > > > LSM_HOOK(int, 0, inode_removexattr, struct mnt_idmap *idmap, > > > struct dentry *dentry, const char *name) > > > +LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry, > > > + const char *name) > > > LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap, > > > struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) > > > LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, > > > diff --git a/include/linux/security.h b/include/linux/security.h > > > index 820899db5276..665bba3e0081 100644 > > > --- a/include/linux/security.h > > > +++ b/include/linux/security.h > > > @@ -374,6 +374,7 @@ int security_inode_getxattr(struct dentry *dentry, const char *name); > > > int security_inode_listxattr(struct dentry *dentry); > > > int security_inode_removexattr(struct mnt_idmap *idmap, > > > struct dentry *dentry, const char *name); > > > +void security_inode_post_removexattr(struct dentry *dentry, const char *name); > > > int security_inode_need_killpriv(struct dentry *dentry); > > > int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry); > > > int security_inode_getsecurity(struct mnt_idmap *idmap, > > > @@ -919,6 +920,10 @@ static inline int security_inode_removexattr(struct mnt_idmap *idmap, > > > return cap_inode_removexattr(idmap, dentry, name); > > > } > > > > > > +static inline void security_inode_post_removexattr(struct dentry *dentry, > > > + const char *name) > > > +{ } > > > > static inline void security_inode_post_removexattr(struct dentry *dentry, const char *name) > > { > > } > > > > > + > > > static inline int security_inode_need_killpriv(struct dentry *dentry) > > > { > > > return cap_inode_need_killpriv(dentry); > > > diff --git a/security/security.c b/security/security.c > > > index 764a6f28b3b9..3947159ba5e9 100644 > > > --- a/security/security.c > > > +++ b/security/security.c > > > @@ -2354,6 +2354,20 @@ int security_inode_removexattr(struct mnt_idmap *idmap, > > > return evm_inode_removexattr(idmap, dentry, name); > > > } > > > > > > +/** > > > + * security_inode_post_removexattr() - Update the inode after a removexattr op > > > + * @dentry: file > > > + * @name: xattr name > > > + * > > > + * Update the inode after a successful removexattr operation. > > > + */ > > > +void security_inode_post_removexattr(struct dentry *dentry, const char *name) > > > +{ > > > + if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) > > > + return; > > > + call_void_hook(inode_post_removexattr, dentry, name); > > > +} > > > + > > > /** > > > * security_inode_need_killpriv() - Check if security_inode_killpriv() required > > > * @dentry: associated dentry > > > -- > > > 2.34.1 > > > > > > These odd splits are everywhere in the patch set. Just (nit)picking some. > > > > It is huge patch set so I don't really get for addign extra lines for no > > good reason. > > Thanks for the review, Jarkko. > > I don't know... to be honest I still prefer to stay within 80 > characters. I agree.
diff --git a/fs/xattr.c b/fs/xattr.c index e7bbb7f57557..4a0280295686 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -552,11 +552,12 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, goto out; error = __vfs_removexattr(idmap, dentry, name); + if (error) + goto out; - if (!error) { - fsnotify_xattr(dentry); - evm_inode_post_removexattr(dentry, name); - } + fsnotify_xattr(dentry); + security_inode_post_removexattr(dentry, name); + evm_inode_post_removexattr(dentry, name); out: return error; diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 995d30336cfa..1153e7163b8b 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -148,6 +148,8 @@ LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name) LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry) LSM_HOOK(int, 0, inode_removexattr, struct mnt_idmap *idmap, struct dentry *dentry, const char *name) +LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry, + const char *name) LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, diff --git a/include/linux/security.h b/include/linux/security.h index 820899db5276..665bba3e0081 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -374,6 +374,7 @@ int security_inode_getxattr(struct dentry *dentry, const char *name); int security_inode_listxattr(struct dentry *dentry); int security_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name); +void security_inode_post_removexattr(struct dentry *dentry, const char *name); int security_inode_need_killpriv(struct dentry *dentry); int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry); int security_inode_getsecurity(struct mnt_idmap *idmap, @@ -919,6 +920,10 @@ static inline int security_inode_removexattr(struct mnt_idmap *idmap, return cap_inode_removexattr(idmap, dentry, name); } +static inline void security_inode_post_removexattr(struct dentry *dentry, + const char *name) +{ } + static inline int security_inode_need_killpriv(struct dentry *dentry) { return cap_inode_need_killpriv(dentry); diff --git a/security/security.c b/security/security.c index 764a6f28b3b9..3947159ba5e9 100644 --- a/security/security.c +++ b/security/security.c @@ -2354,6 +2354,20 @@ int security_inode_removexattr(struct mnt_idmap *idmap, return evm_inode_removexattr(idmap, dentry, name); } +/** + * security_inode_post_removexattr() - Update the inode after a removexattr op + * @dentry: file + * @name: xattr name + * + * Update the inode after a successful removexattr operation. + */ +void security_inode_post_removexattr(struct dentry *dentry, const char *name) +{ + if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) + return; + call_void_hook(inode_post_removexattr, dentry, name); +} + /** * security_inode_need_killpriv() - Check if security_inode_killpriv() required * @dentry: associated dentry