From: Alexey Gladkov <legion@kernel.org>
To: LKML <linux-kernel@vger.kernel.org>,
Linux Containers <containers@lists.linux.dev>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Christian Brauner <brauner@kernel.org>,
"Eric W . Biederman" <ebiederm@xmission.com>,
Kees Cook <keescook@chromium.org>,
Manfred Spraul <manfred@colorfullife.com>
Subject: [PATCH v1] sysctl: Allow change system v ipc sysctls inside ipc namespace
Date: Tue, 12 Jul 2022 18:17:38 +0200 [thread overview]
Message-ID: <54e6b6b1b430537748a7136e854923498443f78a.1657642613.git.legion@kernel.org> (raw)
Rootless containers are not allowed to modify kernel IPC parameters such
as kernel.msgmnb.
It seems to me that we can allow customization of these parameters if
the user has CAP_SYS_RESOURCE in that ipc namespace.
CAP_SYS_RESOURCE is already needed in order to overcome mqueue limits
(msg_max and msgsize_max).
Signed-off-by: Alexey Gladkov <legion@kernel.org>
---
ipc/ipc_sysctl.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c
index ef313ecfb53a..e79452867720 100644
--- a/ipc/ipc_sysctl.c
+++ b/ipc/ipc_sysctl.c
@@ -193,16 +193,19 @@ static int set_is_seen(struct ctl_table_set *set)
static int ipc_permissions(struct ctl_table_header *head, struct ctl_table *table)
{
int mode = table->mode;
-
-#ifdef CONFIG_CHECKPOINT_RESTORE
struct ipc_namespace *ns = current->nsproxy->ipc_ns;
+#ifdef CONFIG_CHECKPOINT_RESTORE
if (((table->data == &ns->ids[IPC_SEM_IDS].next_id) ||
(table->data == &ns->ids[IPC_MSG_IDS].next_id) ||
(table->data == &ns->ids[IPC_SHM_IDS].next_id)) &&
checkpoint_restore_ns_capable(ns->user_ns))
mode = 0666;
+ else
#endif
+ if (ns_capable(ns->user_ns, CAP_SYS_RESOURCE))
+ mode = 0666;
+
return mode;
}
--
2.33.3
next reply other threads:[~2022-07-12 16:24 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-12 16:17 Alexey Gladkov [this message]
2022-07-25 16:16 ` [PATCH v1] sysctl: Allow change system v ipc sysctls inside ipc namespace Eric W. Biederman
2022-08-16 15:42 ` Alexey Gladkov
2022-08-16 15:42 ` [PATCH v1 1/3] " Alexey Gladkov
2022-09-19 15:26 ` Eric W. Biederman
2022-09-20 16:15 ` Alexey Gladkov
2022-09-20 18:08 ` [PATCH v2 0/3] Allow to change ipc/mq " Alexey Gladkov
2022-09-20 18:08 ` [PATCH v2 1/3] sysctl: Allow change system v ipc " Alexey Gladkov
2022-09-21 9:38 ` kernel test robot
2022-09-21 10:41 ` [PATCH v3 0/3] Allow to change ipc/mq " Alexey Gladkov
2022-09-21 10:41 ` [PATCH v3 1/3] sysctl: Allow change system v ipc " Alexey Gladkov
2022-09-21 10:41 ` [PATCH v3 2/3] sysctl: Allow to change limits for posix messages queues Alexey Gladkov
2022-09-21 10:41 ` [PATCH v3 3/3] docs: Add information about ipc sysctls limitations Alexey Gladkov
2024-01-15 15:46 ` [RESEND PATCH v3 0/3] Allow to change ipc/mq sysctls inside ipc namespace Alexey Gladkov
2024-01-15 15:46 ` [RESEND PATCH v3 1/3] sysctl: Allow change system v ipc " Alexey Gladkov
2024-01-15 15:46 ` [RESEND PATCH v3 2/3] docs: Add information about ipc sysctls limitations Alexey Gladkov
2024-01-15 15:46 ` [RESEND PATCH v3 3/3] sysctl: Allow to change limits for posix messages queues Alexey Gladkov
2022-09-20 18:08 ` [PATCH v2 2/3] " Alexey Gladkov
2022-09-20 18:08 ` [PATCH v2 3/3] docs: Add information about ipc sysctls limitations Alexey Gladkov
2022-08-16 15:42 ` [PATCH v1 2/3] sysctl: Allow to change limits for posix messages queues Alexey Gladkov
2022-09-19 15:27 ` Eric W. Biederman
2022-08-16 15:42 ` [PATCH v1 3/3] docs: Add information about ipc sysctls limitations Alexey Gladkov
2022-09-19 15:29 ` Eric W. Biederman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=54e6b6b1b430537748a7136e854923498443f78a.1657642613.git.legion@kernel.org \
--to=legion@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=brauner@kernel.org \
--cc=containers@lists.linux.dev \
--cc=ebiederm@xmission.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=manfred@colorfullife.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).