From: Warner Losh <imp@bsdimp.com>
Date: Fri, 17 Sep 2021 15:16:54 +0000 (-0600)
Subject: bsd-user/mmap.c: assert that target_mprotect cannot fail
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=91a5adda1583fa8a3166bc16d79c67f3c87e958b;p=qemu.git

bsd-user/mmap.c: assert that target_mprotect cannot fail

Similar to the equivalent linux-user change 86abac06c14. 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: Mikaël Urankar <mikael.urankar@gmail.com>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Kyle Evans <kevans@FreeBSD.org>
---

diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c
index 5b6ed5eed1..13cb32dba1 100644
--- a/bsd-user/mmap.c
+++ b/bsd-user/mmap.c
@@ -604,10 +604,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
             }
             if (!(prot & PROT_WRITE)) {
                 ret = target_mprotect(start, len, prot);
-                if (ret != 0) {
-                    start = ret;
-                    goto the_end;
-                }
+                assert(ret == 0);
             }
             goto the_end;
         }