From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 14 Sep 2015 10:31:44 +0000 (+0200)
Subject: linux-user: assert that target_mprotect cannot fail
X-Git-Tag: v2.5.0-rc0~91^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=86abac06c142d20772b3f2e04c9bf02b7936a0b3;p=thirdparty%2Fqemu.git

linux-user: assert that target_mprotect cannot fail

All error conditions that target_mprotect checks are also checked
by target_mmap.  EACCESS cannot happen because we are just removing
PROT_WRITE.  ENOMEM should not happen because we are modifying a
whole VMA (and we have bigger problems anyway if it happens).

Fixes a Coverity false positive, where Coverity complains about
target_mprotect's return value being passed to tb_invalidate_phys_range.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
---

diff --git a/linux-user/mmap.c b/linux-user/mmap.c
index b2126c76fab..5606bcd1645 100644
--- a/linux-user/mmap.c
+++ b/linux-user/mmap.c
@@ -514,10 +514,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
                 goto fail;
             if (!(prot & PROT_WRITE)) {
                 ret = target_mprotect(start, len, prot);
-                if (ret != 0) {
-                    start = ret;
-                    goto the_end;
-                }
+                assert(ret == 0);
             }
             goto the_end;
         }