| Message ID | 20211012180624.447474-2-vgoyal@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fuse: Send file/inode security context during creation | expand |
On 10/12/2021 11:06 AM, Vivek Goyal wrote: > Add the FUSE_SECURITY_CTX flag for the `flags` field of the > fuse_init_out struct. When this flag is set the kernel will append the > security context for a newly created inode to the request (create, > mkdir, mknod, and symlink). The server is responsible for ensuring that > the inode appears atomically (preferrably) with the requested security context. > > For example, if the server is backed by a "real" linux file system then > it can write the security context value to > /proc/thread-self/attr/fscreate before making the syscall to create the > inode. his only works for SELinux, as I've mentioned before. Perhaps: If the server is using SELinux and backed by a "real" linux file system that supports extended attributes it can write the security context value to /proc/thread-self/attr/fscreate before making the syscall to create the inode. > > Vivek: > This patch is slightly modified version of patch from > Chirantan Ekbote <chirantan@chromium.org>. I made changes so that this > patch applies to latest kernel. > > Signed-off-by: Vivek Goyal <vgoyal@redhat.com> > --- > include/uapi/linux/fuse.h | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h > index 36ed092227fa..2fe54c80051a 100644 > --- a/include/uapi/linux/fuse.h > +++ b/include/uapi/linux/fuse.h > @@ -184,6 +184,10 @@ > * > * 7.34 > * - add FUSE_SYNCFS > + * > + * 7.35 > + * - add FUSE_SECURITY_CTX flag for fuse_init_out > + * - add security context to create, mkdir, symlink, and mknod requests > */ > > #ifndef _LINUX_FUSE_H > @@ -219,7 +223,7 @@ > #define FUSE_KERNEL_VERSION 7 > > /** Minor version number of this interface */ > -#define FUSE_KERNEL_MINOR_VERSION 34 > +#define FUSE_KERNEL_MINOR_VERSION 35 > > /** The node ID of the root inode */ > #define FUSE_ROOT_ID 1 > @@ -336,6 +340,8 @@ struct fuse_file_lock { > * write/truncate sgid is killed only if file has group > * execute permission. (Same as Linux VFS behavior). > * FUSE_SETXATTR_EXT: Server supports extended struct fuse_setxattr_in > + * FUSE_SECURITY_CTX: add security context to create, mkdir, symlink, and > + * mknod > */ > #define FUSE_ASYNC_READ (1 << 0) > #define FUSE_POSIX_LOCKS (1 << 1) > @@ -367,6 +373,7 @@ struct fuse_file_lock { > #define FUSE_SUBMOUNTS (1 << 27) > #define FUSE_HANDLE_KILLPRIV_V2 (1 << 28) > #define FUSE_SETXATTR_EXT (1 << 29) > +#define FUSE_SECURITY_CTX (1 << 30) > > /** > * CUSE INIT request/reply flags
On Tue, Oct 12, 2021 at 12:09:35PM -0700, Casey Schaufler wrote: > On 10/12/2021 11:06 AM, Vivek Goyal wrote: > > Add the FUSE_SECURITY_CTX flag for the `flags` field of the > > fuse_init_out struct. When this flag is set the kernel will append the > > security context for a newly created inode to the request (create, > > mkdir, mknod, and symlink). The server is responsible for ensuring that > > the inode appears atomically (preferrably) with the requested security context. > > > > For example, if the server is backed by a "real" linux file system then > > it can write the security context value to > > /proc/thread-self/attr/fscreate before making the syscall to create the > > inode. > > his only works for SELinux, as I've mentioned before. Perhaps: > > If the server is using SELinux and backed by a "real" linux file system > that supports extended attributes it can write the security context value > to /proc/thread-self/attr/fscreate before making the syscall to create > the inode. Agreed, this comment is more accurate. Server needs to be using SELinux. Vivek > > > > > Vivek: > > This patch is slightly modified version of patch from > > Chirantan Ekbote <chirantan@chromium.org>. I made changes so that this > > patch applies to latest kernel. > > > > Signed-off-by: Vivek Goyal <vgoyal@redhat.com> > > --- > > include/uapi/linux/fuse.h | 9 ++++++++- > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h > > index 36ed092227fa..2fe54c80051a 100644 > > --- a/include/uapi/linux/fuse.h > > +++ b/include/uapi/linux/fuse.h > > @@ -184,6 +184,10 @@ > > * > > * 7.34 > > * - add FUSE_SYNCFS > > + * > > + * 7.35 > > + * - add FUSE_SECURITY_CTX flag for fuse_init_out > > + * - add security context to create, mkdir, symlink, and mknod requests > > */ > > > > #ifndef _LINUX_FUSE_H > > @@ -219,7 +223,7 @@ > > #define FUSE_KERNEL_VERSION 7 > > > > /** Minor version number of this interface */ > > -#define FUSE_KERNEL_MINOR_VERSION 34 > > +#define FUSE_KERNEL_MINOR_VERSION 35 > > > > /** The node ID of the root inode */ > > #define FUSE_ROOT_ID 1 > > @@ -336,6 +340,8 @@ struct fuse_file_lock { > > * write/truncate sgid is killed only if file has group > > * execute permission. (Same as Linux VFS behavior). > > * FUSE_SETXATTR_EXT: Server supports extended struct fuse_setxattr_in > > + * FUSE_SECURITY_CTX: add security context to create, mkdir, symlink, and > > + * mknod > > */ > > #define FUSE_ASYNC_READ (1 << 0) > > #define FUSE_POSIX_LOCKS (1 << 1) > > @@ -367,6 +373,7 @@ struct fuse_file_lock { > > #define FUSE_SUBMOUNTS (1 << 27) > > #define FUSE_HANDLE_KILLPRIV_V2 (1 << 28) > > #define FUSE_SETXATTR_EXT (1 << 29) > > +#define FUSE_SECURITY_CTX (1 << 30) > > > > /** > > * CUSE INIT request/reply flags >
diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 36ed092227fa..2fe54c80051a 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -184,6 +184,10 @@ * * 7.34 * - add FUSE_SYNCFS + * + * 7.35 + * - add FUSE_SECURITY_CTX flag for fuse_init_out + * - add security context to create, mkdir, symlink, and mknod requests */ #ifndef _LINUX_FUSE_H @@ -219,7 +223,7 @@ #define FUSE_KERNEL_VERSION 7 /** Minor version number of this interface */ -#define FUSE_KERNEL_MINOR_VERSION 34 +#define FUSE_KERNEL_MINOR_VERSION 35 /** The node ID of the root inode */ #define FUSE_ROOT_ID 1 @@ -336,6 +340,8 @@ struct fuse_file_lock { * write/truncate sgid is killed only if file has group * execute permission. (Same as Linux VFS behavior). * FUSE_SETXATTR_EXT: Server supports extended struct fuse_setxattr_in + * FUSE_SECURITY_CTX: add security context to create, mkdir, symlink, and + * mknod */ #define FUSE_ASYNC_READ (1 << 0) #define FUSE_POSIX_LOCKS (1 << 1) @@ -367,6 +373,7 @@ struct fuse_file_lock { #define FUSE_SUBMOUNTS (1 << 27) #define FUSE_HANDLE_KILLPRIV_V2 (1 << 28) #define FUSE_SETXATTR_EXT (1 << 29) +#define FUSE_SECURITY_CTX (1 << 30) /** * CUSE INIT request/reply flags
Add the FUSE_SECURITY_CTX flag for the `flags` field of the fuse_init_out struct. When this flag is set the kernel will append the security context for a newly created inode to the request (create, mkdir, mknod, and symlink). The server is responsible for ensuring that the inode appears atomically (preferrably) with the requested security context. For example, if the server is backed by a "real" linux file system then it can write the security context value to /proc/thread-self/attr/fscreate before making the syscall to create the inode. Vivek: This patch is slightly modified version of patch from Chirantan Ekbote <chirantan@chromium.org>. I made changes so that this patch applies to latest kernel. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> --- include/uapi/linux/fuse.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)