From: Julius Hemanth Pitti <jpitti@cisco.com>
To: keescook@chromium.org, yzaikin@google.com, mcgrof@kernel.org
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
akpm@linux-foundation.org, mingo@elte.hu,
viro@zeniv.linux.org.uk, xe-linux-external@cisco.com,
Julius Hemanth Pitti <jpitti@cisco.com>
Subject: [PATCH] proc/sysctl: make protected_* world readable
Date: Thu, 9 Jul 2020 16:51:15 -0700 [thread overview]
Message-ID: <20200709235115.56954-1-jpitti@cisco.com> (raw)
protected_* files have 600 permissions which prevents
non-superuser from reading them.
Container like "AWS greengrass" refuse to launch unless
protected_hardlinks and protected_symlinks are set. When
containers like these run with "userns-remap" or "--user"
mapping container's root to non-superuser on host, they
fail to run due to denied read access to these files.
As these protections are hardly a secret, and do not
possess any security risk, making them world readable.
Though above greengrass usecase needs read access to
only protected_hardlinks and protected_symlinks files,
setting all other protected_* files to 644 to keep
consistency.
Fixes: 800179c9b8a1 ("fs: add link restrictions")
Signed-off-by: Julius Hemanth Pitti <jpitti@cisco.com>
---
kernel/sysctl.c | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index db1ce7a..aeca2fd 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -3223,7 +3223,7 @@ int proc_do_static_key(struct ctl_table *table, int write,
.procname = "protected_symlinks",
.data = &sysctl_protected_symlinks,
.maxlen = sizeof(int),
- .mode = 0600,
+ .mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE,
@@ -3232,7 +3232,7 @@ int proc_do_static_key(struct ctl_table *table, int write,
.procname = "protected_hardlinks",
.data = &sysctl_protected_hardlinks,
.maxlen = sizeof(int),
- .mode = 0600,
+ .mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE,
@@ -3241,7 +3241,7 @@ int proc_do_static_key(struct ctl_table *table, int write,
.procname = "protected_fifos",
.data = &sysctl_protected_fifos,
.maxlen = sizeof(int),
- .mode = 0600,
+ .mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = &two,
@@ -3250,7 +3250,7 @@ int proc_do_static_key(struct ctl_table *table, int write,
.procname = "protected_regular",
.data = &sysctl_protected_regular,
.maxlen = sizeof(int),
- .mode = 0600,
+ .mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = &two,
--
1.7.1
next reply other threads:[~2020-07-09 23:58 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-09 23:51 Julius Hemanth Pitti [this message]
2020-07-10 4:31 ` [PATCH] proc/sysctl: make protected_* world readable Kees Cook
2020-07-29 0:03 ` Luis Chamberlain
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