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-rw-r--r--kernel/sys.c53
1 files changed, 49 insertions, 4 deletions
diff --git a/kernel/sys.c b/kernel/sys.c
index a101ba36c444..18ee1d2f6474 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -37,6 +37,8 @@
#include <linux/fs_struct.h>
#include <linux/gfp.h>
#include <linux/syscore_ops.h>
+#include <linux/version.h>
+#include <linux/ctype.h>
#include <linux/compat.h>
#include <linux/syscalls.h>
@@ -44,6 +46,8 @@
#include <linux/user_namespace.h>
#include <linux/kmsg_dump.h>
+/* Move somewhere else to avoid recompiling? */
+#include <generated/utsrelease.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -621,11 +625,18 @@ static int set_user(struct cred *new)
if (!new_user)
return -EAGAIN;
+ /*
+ * We don't fail in case of NPROC limit excess here because too many
+ * poorly written programs don't check set*uid() return code, assuming
+ * it never fails if called by root. We may still enforce NPROC limit
+ * for programs doing set*uid()+execve() by harmlessly deferring the
+ * failure to the execve() stage.
+ */
if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
- new_user != INIT_USER) {
- free_uid(new_user);
- return -EAGAIN;
- }
+ new_user != INIT_USER)
+ current->flags |= PF_NPROC_EXCEEDED;
+ else
+ current->flags &= ~PF_NPROC_EXCEEDED;
free_uid(new->user);
new->user = new_user;
@@ -1154,6 +1165,34 @@ DECLARE_RWSEM(uts_sem);
#define override_architecture(name) 0
#endif
+/*
+ * Work around broken programs that cannot handle "Linux 3.0".
+ * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
+ */
+static int override_release(char __user *release, int len)
+{
+ int ret = 0;
+ char buf[len];
+
+ if (current->personality & UNAME26) {
+ char *rest = UTS_RELEASE;
+ int ndots = 0;
+ unsigned v;
+
+ while (*rest) {
+ if (*rest == '.' && ++ndots >= 3)
+ break;
+ if (!isdigit(*rest) && *rest != '.')
+ break;
+ rest++;
+ }
+ v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40;
+ snprintf(buf, len, "2.6.%u%s", v, rest);
+ ret = copy_to_user(release, buf, len);
+ }
+ return ret;
+}
+
SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
{
int errno = 0;
@@ -1163,6 +1202,8 @@ SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
errno = -EFAULT;
up_read(&uts_sem);
+ if (!errno && override_release(name->release, sizeof(name->release)))
+ errno = -EFAULT;
if (!errno && override_architecture(name))
errno = -EFAULT;
return errno;
@@ -1184,6 +1225,8 @@ SYSCALL_DEFINE1(uname, struct old_utsname __user *, name)
error = -EFAULT;
up_read(&uts_sem);
+ if (!error && override_release(name->release, sizeof(name->release)))
+ error = -EFAULT;
if (!error && override_architecture(name))
error = -EFAULT;
return error;
@@ -1218,6 +1261,8 @@ SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name)
if (!error && override_architecture(name))
error = -EFAULT;
+ if (!error && override_release(name->release, sizeof(name->release)))
+ error = -EFAULT;
return error ? -EFAULT : 0;
}
#endif
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