Re: [PATCH v2 1/3] seccomp: Add find_notification helper
From: Christian Brauner <hidden>
Date: 2020-05-29 09:58:09
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lkml
On Thu, May 28, 2020 at 04:08:56AM -0700, Sargun Dhillon wrote:
This adds a helper which can iterate through a seccomp_filter to find a notification matching an ID. It removes several replicated chunks of code. Signed-off-by: Sargun Dhillon <redacted> Cc: Matt Denton <redacted> Cc: Kees Cook <redacted>, Cc: Jann Horn <jannh@google.com>, Cc: Robert Sesek <redacted>, Cc: Chris Palmer <redacted> Cc: Christian Brauner <redacted> Cc: Tycho Andersen <redacted> ---
A single nit below otherwise: Acked-by: Christian Brauner <redacted>
quoted hunk ↗ jump to hunk
kernel/seccomp.c | 51 ++++++++++++++++++++++++------------------------ 1 file changed, 25 insertions(+), 26 deletions(-)diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 55a6184f5990..94ae4c7502cc 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c@@ -1021,10 +1021,25 @@ static int seccomp_notify_release(struct inode *inode, struct file *file) return 0; } +/* must be called with notif_lock held */ +static inline struct seccomp_knotif * +find_notification(struct seccomp_filter *filter, u64 id) +{ + struct seccomp_knotif *cur; + + list_for_each_entry(cur, &filter->notif->notifications, list) { + if (cur->id == id) + return cur; + } + + return NULL; +} + + static long seccomp_notify_recv(struct seccomp_filter *filter, void __user *buf) { - struct seccomp_knotif *knotif = NULL, *cur; + struct seccomp_knotif *knotif, *cur; struct seccomp_notif unotif; ssize_t ret;@@ -1078,14 +1093,8 @@ static long seccomp_notify_recv(struct seccomp_filter *filter, * may have died when we released the lock, so we need to make * sure it's still around. */ - knotif = NULL; mutex_lock(&filter->notify_lock); - list_for_each_entry(cur, &filter->notif->notifications, list) { - if (cur->id == unotif.id) { - knotif = cur; - break; - } - } + knotif = find_notification(filter, unotif.id); if (knotif) {
Nit: additional \n which isn't present before any of the other new find_notification() invocations.