diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 17:55:21 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 17:55:21 -0700 |
| commit | bbb20089a3275a19e475dbc21320c3742e3ca423 (patch) | |
| tree | 216fdc1cbef450ca688135c5b8969169482d9a48 /security/commoncap.c | |
| parent | 3e48e656903e9fd8bc805c6a2c4264d7808d315b (diff) | |
| parent | 657a77fa7284d8ae28dfa48f1dc5d919bf5b2843 (diff) | |
Merge branch 'dmaengine' into async-tx-next
Conflicts:
crypto/async_tx/async_xor.c
drivers/dma/ioat/dma_v2.h
drivers/dma/ioat/pci.c
drivers/md/raid5.c
Diffstat (limited to 'security/commoncap.c')
| -rw-r--r-- | security/commoncap.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/security/commoncap.c b/security/commoncap.c index beac0258c2a..48b7e0228fa 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -28,6 +28,28 @@ #include <linux/prctl.h> #include <linux/securebits.h> +/* + * If a non-root user executes a setuid-root binary in + * !secure(SECURE_NOROOT) mode, then we raise capabilities. + * However if fE is also set, then the intent is for only + * the file capabilities to be applied, and the setuid-root + * bit is left on either to change the uid (plausible) or + * to get full privilege on a kernel without file capabilities + * support. So in that case we do not raise capabilities. + * + * Warn if that happens, once per boot. + */ +static void warn_setuid_and_fcaps_mixed(char *fname) +{ + static int warned; + if (!warned) { + printk(KERN_INFO "warning: `%s' has both setuid-root and" + " effective capabilities. Therefore not raising all" + " capabilities.\n", fname); + warned = 1; + } +} + int cap_netlink_send(struct sock *sk, struct sk_buff *skb) { NETLINK_CB(skb).eff_cap = current_cap(); @@ -464,6 +486,15 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) if (!issecure(SECURE_NOROOT)) { /* + * If the legacy file capability is set, then don't set privs + * for a setuid root binary run by a non-root user. Do set it + * for a root user just to cause least surprise to an admin. + */ + if (effective && new->uid != 0 && new->euid == 0) { + warn_setuid_and_fcaps_mixed(bprm->filename); + goto skip; + } + /* * To support inheritance of root-permissions and suid-root * executables under compatibility mode, we override the * capability sets for the file. @@ -478,6 +509,7 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) if (new->euid == 0) effective = true; } +skip: /* Don't let someone trace a set[ug]id/setpcap binary with the revised * credentials unless they have the appropriate permit |