From: Stacey Son <sson@FreeBSD.org>

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Karim Taha <kariem.taha2.7@gmail.com>
---
 bsd-user/bsd-mem.h            | 23 +++++++++++++++++++++++
 bsd-user/freebsd/os-syscall.c |  4 ++++
 2 files changed, 27 insertions(+)

diff --git a/bsd-user/bsd-mem.h b/bsd-user/bsd-mem.h
index f76881519c..edbccd3111 100644
--- a/bsd-user/bsd-mem.h
+++ b/bsd-user/bsd-mem.h
@@ -144,4 +144,27 @@ static inline abi_long do_bsd_minherit(abi_long addr, abi_long len,
     return get_errno(minherit(g2h_untagged(addr), len, inherit));
 }
 
+/* mincore(2) */
+static inline abi_long do_bsd_mincore(abi_ulong target_addr, abi_ulong len,
+        abi_ulong target_vec)
+{
+    abi_long ret;
+    void *p, *a;
+
+    a = lock_user(VERIFY_WRITE, target_addr, len, 0);
+    if (a == NULL) {
+        return -TARGET_EFAULT;
+    }
+    p = lock_user_string(target_vec);
+    if (p == NULL) {
+        unlock_user(a, target_addr, 0);
+        return -TARGET_EFAULT;
+    }
+    ret = get_errno(mincore(a, len, p));
+    unlock_user(p, target_vec, ret);
+    unlock_user(a, target_addr, 0);
+
+    return ret;
+}
+
 #endif /* BSD_USER_BSD_MEM_H */
diff --git a/bsd-user/freebsd/os-syscall.c b/bsd-user/freebsd/os-syscall.c
index 96469f6a63..1db0907504 100644
--- a/bsd-user/freebsd/os-syscall.c
+++ b/bsd-user/freebsd/os-syscall.c
@@ -527,6 +527,10 @@ static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1,
         ret = do_bsd_minherit(arg1, arg2, arg3);
         break;
 
+    case TARGET_FREEBSD_NR_mincore: /* mincore(2) */
+        ret = do_bsd_mincore(arg1, arg2, arg3);
+        break;
+
 #if defined(__FreeBSD_version) && __FreeBSD_version >= 1300048
     case TARGET_FREEBSD_NR_shm_open2: /* shm_open2(2) */
         ret = do_freebsd_shm_open2(arg1, arg2, arg3, arg4, arg5);
-- 
2.40.0

On 8/19/23 02:48, Karim Taha wrote:
> +/* mincore(2) */
> +static inline abi_long do_bsd_mincore(abi_ulong target_addr, abi_ulong len,
> +        abi_ulong target_vec)
> +{
> +    abi_long ret;
> +    void *p, *a;
> +
> +    a = lock_user(VERIFY_WRITE, target_addr, len, 0);
> +    if (a == NULL) {
> +        return -TARGET_EFAULT;
> +    }
> +    p = lock_user_string(target_vec);
> +    if (p == NULL) {
> +        unlock_user(a, target_addr, 0);
> +        return -TARGET_EFAULT;
> +    }
> +    ret = get_errno(mincore(a, len, p));
> +    unlock_user(p, target_vec, ret);
> +    unlock_user(a, target_addr, 0);
> +
> +    return ret;

This is wrong.

(1) VERIFY_WRITE is incorrect.  Here you need a combination of guest_range_valid_untagged 
and page_check_range(addr, len, PAGE_VALID).

(2) vec is not a string, it is an array of size DIV_ROUND_UP(len, TARGET_PAGE_SIZE).  For 
that, you do want lock_user(VERIFY_WRITE).


r~

On Sat, Aug 19, 2023 at 3:49 AM Karim Taha <kariem.taha2.7@gmail.com> wrote:

> From: Stacey Son <sson@FreeBSD.org>
>
> Signed-off-by: Stacey Son <sson@FreeBSD.org>
> Signed-off-by: Karim Taha <kariem.taha2.7@gmail.com>
> ---
>  bsd-user/bsd-mem.h            | 23 +++++++++++++++++++++++
>  bsd-user/freebsd/os-syscall.c |  4 ++++
>  2 files changed, 27 insertions(+)
>

Reviewed-by: Warner Losh <imp@bsdimp.com>