diff options
| author | John Johansen <john.johansen@canonical.com> | 2020-01-02 05:31:22 -0800 |
|---|---|---|
| committer | John Johansen <john.johansen@canonical.com> | 2020-01-04 15:56:44 -0800 |
| commit | 8c62ed27a12c00e3db1c9f04bc0f272bdbb06734 (patch) | |
| tree | 7bbe5954a3d15944b17e1cc732eb0f479276ffda /security/apparmor/apparmorfs.c | |
| parent | 20d4e80d255dd7cfecb53743bc550ebcad04549d (diff) | |
| download | linux-8c62ed27a12c00e3db1c9f04bc0f272bdbb06734.tar.gz | |
apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock
aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a
context protected by an rcu_read_lock. This can not be done as
vfs_getxattr_alloc() may sleep regardles of the gfp_t value being
passed to it.
Fix this by breaking the rcu_read_lock on the policy search when the
xattr match feature is requested and restarting the search if a policy
changes occur.
Fixes: 8e51f9087f40 ("apparmor: Add support for attaching profiles via xattr, presence and value")
Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Diffstat (limited to 'security/apparmor/apparmorfs.c')
| -rw-r--r-- | security/apparmor/apparmorfs.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 09996f2552ee..47aff8700547 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -623,7 +623,7 @@ static __poll_t ns_revision_poll(struct file *file, poll_table *pt) void __aa_bump_ns_revision(struct aa_ns *ns) { - ns->revision++; + WRITE_ONCE(ns->revision, ns->revision + 1); wake_up_interruptible(&ns->wait); } |