On Thu, Apr 24, 2025 at 10:55 AM Stephen Smalley <stephen.smalley.work@xxxxxxxxx> wrote: > > On Thu, Apr 24, 2025 at 9:53 AM Stephen Smalley > <stephen.smalley.work@xxxxxxxxx> wrote: > > > > On Thu, Apr 24, 2025 at 9:12 AM Greg Kroah-Hartman > > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > > On Thu, Apr 24, 2025 at 08:46:43AM -0400, Stephen Smalley wrote: > > > > The vfs has long had a fallback to obtain the security.* xattrs from the > > > > LSM when the filesystem does not implement its own listxattr, but > > > > shmem/tmpfs and kernfs later gained their own xattr handlers to support > > > > other xattrs. Unfortunately, as a side effect, tmpfs and kernfs-based > > > > filesystems like sysfs no longer return the synthetic security.* xattr > > > > names via listxattr unless they are explicitly set by userspace or > > > > initially set upon inode creation after policy load. coreutils has > > > > recently switched from unconditionally invoking getxattr for security.* > > > > for ls -Z via libselinux to only doing so if listxattr returns the xattr > > > > name, breaking ls -Z of such inodes. > > > > > > > > Before: > > > > $ getfattr -m.* /run/initramfs > > > > <no output> > > > > $ getfattr -m.* /sys/kernel/fscaps > > > > <no output> > > > > > > > > After: > > > > $ getfattr -m.* /run/initramfs > > > > security.selinux > > > > $ getfattr -m.* /sys/kernel/fscaps > > > > security.selinux > > > > > > > > Link: https://lore.kernel.org/selinux/CAFqZXNtF8wDyQajPCdGn=iOawX4y77ph0EcfcqcUUj+T87FKyA@xxxxxxxxxxxxxx/ > > > > Link: https://lore.kernel.org/selinux/20250423175728.3185-2-stephen.smalley.work@xxxxxxxxx/ > > > > Signed-off-by: Stephen Smalley <stephen.smalley.work@xxxxxxxxx> > > > > > > As this "changed" in the past, shouldn't it have a "Fixes:" tag? > > > > Yes, I'll add that on v2. Also appears that it doesn't quite correctly > > handle the case where listxattr() is called with size == 0 to probe > > for the required size. > > And doesn't correctly handle the case where the list size exceeds the > original buffer size. On second look, this can be done more simply and > safely in simple_xattr_list() itself, avoiding the need to modify > shmem/tmpfs and kernfs. I'll submit an updated patch. Submitted here, https://lore.kernel.org/selinux/20250424152822.2719-1-stephen.smalley.work@xxxxxxxxx/ Sorry I forgot the Fixes tag again but added it in a reply.
