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-rw-r--r--kernel/auditsc.c6
-rw-r--r--kernel/capability.c104
-rw-r--r--kernel/umh.c41
3 files changed, 64 insertions, 87 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 93d0b87f3283..addeed3df15d 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1295,15 +1295,11 @@ out:
static void audit_log_cap(struct audit_buffer *ab, char *prefix,
kernel_cap_t *cap)
{
- int i;
-
if (cap_isclear(*cap)) {
audit_log_format(ab, " %s=0", prefix);
return;
}
- audit_log_format(ab, " %s=", prefix);
- CAP_FOR_EACH_U32(i)
- audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]);
+ audit_log_format(ab, " %s=%016llx", prefix, cap->val);
}
static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
diff --git a/kernel/capability.c b/kernel/capability.c
index 339a44dfe2f4..3e058f41df32 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -20,13 +20,6 @@
#include <linux/user_namespace.h>
#include <linux/uaccess.h>
-/*
- * Leveraged for setting/resetting capabilities
- */
-
-const kernel_cap_t __cap_empty_set = CAP_EMPTY_SET;
-EXPORT_SYMBOL(__cap_empty_set);
-
int file_caps_enabled = 1;
static int __init file_caps_disable(char *str)
@@ -151,6 +144,7 @@ SYSCALL_DEFINE2(capget, cap_user_header_t, header, cap_user_data_t, dataptr)
pid_t pid;
unsigned tocopy;
kernel_cap_t pE, pI, pP;
+ struct __user_cap_data_struct kdata[2];
ret = cap_validate_magic(header, &tocopy);
if ((dataptr == NULL) || (ret != 0))
@@ -163,42 +157,46 @@ SYSCALL_DEFINE2(capget, cap_user_header_t, header, cap_user_data_t, dataptr)
return -EINVAL;
ret = cap_get_target_pid(pid, &pE, &pI, &pP);
- if (!ret) {
- struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
- unsigned i;
-
- for (i = 0; i < tocopy; i++) {
- kdata[i].effective = pE.cap[i];
- kdata[i].permitted = pP.cap[i];
- kdata[i].inheritable = pI.cap[i];
- }
-
- /*
- * Note, in the case, tocopy < _KERNEL_CAPABILITY_U32S,
- * we silently drop the upper capabilities here. This
- * has the effect of making older libcap
- * implementations implicitly drop upper capability
- * bits when they perform a: capget/modify/capset
- * sequence.
- *
- * This behavior is considered fail-safe
- * behavior. Upgrading the application to a newer
- * version of libcap will enable access to the newer
- * capabilities.
- *
- * An alternative would be to return an error here
- * (-ERANGE), but that causes legacy applications to
- * unexpectedly fail; the capget/modify/capset aborts
- * before modification is attempted and the application
- * fails.
- */
- if (copy_to_user(dataptr, kdata, tocopy
- * sizeof(struct __user_cap_data_struct))) {
- return -EFAULT;
- }
- }
+ if (ret)
+ return ret;
- return ret;
+ /*
+ * Annoying legacy format with 64-bit capabilities exposed
+ * as two sets of 32-bit fields, so we need to split the
+ * capability values up.
+ */
+ kdata[0].effective = pE.val; kdata[1].effective = pE.val >> 32;
+ kdata[0].permitted = pP.val; kdata[1].permitted = pP.val >> 32;
+ kdata[0].inheritable = pI.val; kdata[1].inheritable = pI.val >> 32;
+
+ /*
+ * Note, in the case, tocopy < _KERNEL_CAPABILITY_U32S,
+ * we silently drop the upper capabilities here. This
+ * has the effect of making older libcap
+ * implementations implicitly drop upper capability
+ * bits when they perform a: capget/modify/capset
+ * sequence.
+ *
+ * This behavior is considered fail-safe
+ * behavior. Upgrading the application to a newer
+ * version of libcap will enable access to the newer
+ * capabilities.
+ *
+ * An alternative would be to return an error here
+ * (-ERANGE), but that causes legacy applications to
+ * unexpectedly fail; the capget/modify/capset aborts
+ * before modification is attempted and the application
+ * fails.
+ */
+ if (copy_to_user(dataptr, kdata, tocopy * sizeof(kdata[0])))
+ return -EFAULT;
+
+ return 0;
+}
+
+static kernel_cap_t mk_kernel_cap(u32 low, u32 high)
+{
+ return (kernel_cap_t) { (low | ((u64)high << 32)) & CAP_VALID_MASK };
}
/**
@@ -221,8 +219,8 @@ SYSCALL_DEFINE2(capget, cap_user_header_t, header, cap_user_data_t, dataptr)
*/
SYSCALL_DEFINE2(capset, cap_user_header_t, header, const cap_user_data_t, data)
{
- struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
- unsigned i, tocopy, copybytes;
+ struct __user_cap_data_struct kdata[2] = { { 0, }, };
+ unsigned tocopy, copybytes;
kernel_cap_t inheritable, permitted, effective;
struct cred *new;
int ret;
@@ -246,21 +244,9 @@ SYSCALL_DEFINE2(capset, cap_user_header_t, header, const cap_user_data_t, data)
if (copy_from_user(&kdata, data, copybytes))
return -EFAULT;
- for (i = 0; i < tocopy; i++) {
- effective.cap[i] = kdata[i].effective;
- permitted.cap[i] = kdata[i].permitted;
- inheritable.cap[i] = kdata[i].inheritable;
- }
- while (i < _KERNEL_CAPABILITY_U32S) {
- effective.cap[i] = 0;
- permitted.cap[i] = 0;
- inheritable.cap[i] = 0;
- i++;
- }
-
- effective.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK;
- permitted.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK;
- inheritable.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK;
+ effective = mk_kernel_cap(kdata[0].effective, kdata[1].effective);
+ permitted = mk_kernel_cap(kdata[0].permitted, kdata[1].permitted);
+ inheritable = mk_kernel_cap(kdata[0].inheritable, kdata[1].inheritable);
new = prepare_creds();
if (!new)
diff --git a/kernel/umh.c b/kernel/umh.c
index fbf872c624cb..2a4708277335 100644
--- a/kernel/umh.c
+++ b/kernel/umh.c
@@ -501,9 +501,9 @@ static int proc_cap_handler(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
struct ctl_table t;
- unsigned long cap_array[_KERNEL_CAPABILITY_U32S];
- kernel_cap_t new_cap;
- int err, i;
+ unsigned long cap_array[2];
+ kernel_cap_t new_cap, *cap;
+ int err;
if (write && (!capable(CAP_SETPCAP) ||
!capable(CAP_SYS_MODULE)))
@@ -514,14 +514,16 @@ static int proc_cap_handler(struct ctl_table *table, int write,
* userspace if this is a read.
*/
spin_lock(&umh_sysctl_lock);
- for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++) {
- if (table->data == CAP_BSET)
- cap_array[i] = usermodehelper_bset.cap[i];
- else if (table->data == CAP_PI)
- cap_array[i] = usermodehelper_inheritable.cap[i];
- else
- BUG();
- }
+ if (table->data == CAP_BSET)
+ cap = &usermodehelper_bset;
+ else if (table->data == CAP_PI)
+ cap = &usermodehelper_inheritable;
+ else
+ BUG();
+
+ /* Legacy format: capabilities are exposed as two 32-bit values */
+ cap_array[0] = (u32) cap->val;
+ cap_array[1] = cap->val >> 32;
spin_unlock(&umh_sysctl_lock);
t = *table;
@@ -535,22 +537,15 @@ static int proc_cap_handler(struct ctl_table *table, int write,
if (err < 0)
return err;
- /*
- * convert from the sysctl array of ulongs to the kernel_cap_t
- * internal representation
- */
- for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++)
- new_cap.cap[i] = cap_array[i];
+ new_cap.val = (u32)cap_array[0];
+ new_cap.val += (u64)cap_array[1] << 32;
/*
* Drop everything not in the new_cap (but don't add things)
*/
if (write) {
spin_lock(&umh_sysctl_lock);
- if (table->data == CAP_BSET)
- usermodehelper_bset = cap_intersect(usermodehelper_bset, new_cap);
- if (table->data == CAP_PI)
- usermodehelper_inheritable = cap_intersect(usermodehelper_inheritable, new_cap);
+ *cap = cap_intersect(*cap, new_cap);
spin_unlock(&umh_sysctl_lock);
}
@@ -561,14 +556,14 @@ struct ctl_table usermodehelper_table[] = {
{
.procname = "bset",
.data = CAP_BSET,
- .maxlen = _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
+ .maxlen = 2 * sizeof(unsigned long),
.mode = 0600,
.proc_handler = proc_cap_handler,
},
{
.procname = "inheritable",
.data = CAP_PI,
- .maxlen = _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
+ .maxlen = 2 * sizeof(unsigned long),
.mode = 0600,
.proc_handler = proc_cap_handler,
},
generated by cgit (git 2.34.1) at 2024-06-28 19:03:24 +0000