From: John Johansen Date: Sat, 14 Sep 2019 05:24:23 +0000 (-0700) Subject: apparmor: reduce rcu_read_lock scope for aa_file_perm mediation X-Git-Tag: v5.5-rc1~58^2~1 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=bce4e7e9c45ef97ac1e30b9cb4adc25b5b5a7cfa;p=linux.git apparmor: reduce rcu_read_lock scope for aa_file_perm mediation Now that the buffers allocation has changed and no longer needs the full mediation under an rcu_read_lock, reduce the rcu_read_lock scope to only where it is necessary. Fixes: df323337e507 ("apparmor: Use a memory pool instead per-CPU caches") Signed-off-by: John Johansen --- diff --git a/security/apparmor/file.c b/security/apparmor/file.c index ab56e1994b01..37d62ecec29d 100644 --- a/security/apparmor/file.c +++ b/security/apparmor/file.c @@ -621,7 +621,8 @@ int aa_file_perm(const char *op, struct aa_label *label, struct file *file, fctx = file_ctx(file); rcu_read_lock(); - flabel = rcu_dereference(fctx->label); + flabel = aa_get_newest_label(rcu_dereference(fctx->label)); + rcu_read_unlock(); AA_BUG(!flabel); /* revalidate access, if task is unconfined, or the cached cred @@ -646,8 +647,7 @@ int aa_file_perm(const char *op, struct aa_label *label, struct file *file, error = __file_sock_perm(op, label, flabel, file, request, denied); done: - rcu_read_unlock(); - + aa_put_label(flabel); return error; }