| Message ID | 20230110022554.1186499-2-mcgrof@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fs: kill old ms_* flags for internal sb | expand |
On Mon, Jan 09, 2023 at 06:25:52PM -0800, Luis Chamberlain wrote: > Commit 2ea3ffb7782 ("apparmor: add mount mediation") John Johansen > added mount mediation support. However just the day before this commit > David Howells modified the internal sb flags through commit e462ec50cb5 > ("VFS: Differentiate mount flags (MS_*) from internal superblock flags"). > > Use the modified sb flags to make things clear and avoid further uses > of the old MS_* flags for superblock internal flags. This will let us > later remove the MS_* sb internal flags as userspace should not be > using them. > > This commit does not fix anything as the old flags used map to the > same bitmask, this just tidies things up. I split up the flags to > make it clearer which ones are for the superblock and used internally. I don't think that's right. apparmor_sb_mount() gets (almost) raw flags from mount(2); incidentally, MS_MGC_MSK removal directly above the modified line is BS since _that_ has already been done by the caller. Note that the same function explicitly checks for MS_MOVE, etc. in the same argument. > @@ -74,7 +74,7 @@ static void audit_mnt_flags(struct audit_buffer *ab, unsigned long flags) > audit_log_format(ab, ", iversion"); > if (flags & MS_STRICTATIME) > audit_log_format(ab, ", strictatime"); > - if (flags & MS_NOUSER) > + if (flags & SB_NOUSER) > audit_log_format(ab, ", nouser"); > } Umm... How does one trigger that one?
diff --git a/security/apparmor/include/mount.h b/security/apparmor/include/mount.h index a710683b2496..f90e03405e38 100644 --- a/security/apparmor/include/mount.h +++ b/security/apparmor/include/mount.h @@ -23,7 +23,8 @@ #define AA_AUDIT_DATA 0x40 #define AA_MNT_CONT_MATCH 0x40 -#define AA_MS_IGNORE_MASK (MS_KERNMOUNT | MS_NOSEC | MS_ACTIVE | MS_BORN) +#define AA_MS_IGNORE_MASK (MS_KERNMOUNT) +#define AA_SB_IGNORE_MASK (SB_NOSEC | SB_ACTIVE | SB_BORN) int aa_remount(struct aa_label *label, const struct path *path, unsigned long flags, void *data); diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index c6728a629437..f3880956bffd 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -583,6 +583,7 @@ static int apparmor_sb_mount(const char *dev_name, const struct path *path, flags &= ~MS_MGC_MSK; flags &= ~AA_MS_IGNORE_MASK; + flags &= ~AA_SB_IGNORE_MASK; label = __begin_current_label_crit_section(); if (!unconfined(label)) { diff --git a/security/apparmor/mount.c b/security/apparmor/mount.c index cdfa430ae216..c37c451e8226 100644 --- a/security/apparmor/mount.c +++ b/security/apparmor/mount.c @@ -74,7 +74,7 @@ static void audit_mnt_flags(struct audit_buffer *ab, unsigned long flags) audit_log_format(ab, ", iversion"); if (flags & MS_STRICTATIME) audit_log_format(ab, ", strictatime"); - if (flags & MS_NOUSER) + if (flags & SB_NOUSER) audit_log_format(ab, ", nouser"); }
Commit 2ea3ffb7782 ("apparmor: add mount mediation") John Johansen added mount mediation support. However just the day before this commit David Howells modified the internal sb flags through commit e462ec50cb5 ("VFS: Differentiate mount flags (MS_*) from internal superblock flags"). Use the modified sb flags to make things clear and avoid further uses of the old MS_* flags for superblock internal flags. This will let us later remove the MS_* sb internal flags as userspace should not be using them. This commit does not fix anything as the old flags used map to the same bitmask, this just tidies things up. I split up the flags to make it clearer which ones are for the superblock and used internally. Cc: John Johansen <john.johansen@canonical.com> Cc: David Howells <dhowells@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> --- security/apparmor/include/mount.h | 3 ++- security/apparmor/lsm.c | 1 + security/apparmor/mount.c | 2 +- 3 files changed, 4 insertions(+), 2 deletions(-)