diff options
Diffstat (limited to 'linux-user/syscall.c')
| -rw-r--r-- | linux-user/syscall.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 29bac79b61..d6605b8b50 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -9716,8 +9716,15 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, arg4 = arg5; arg5 = arg6; } - if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0))) - return -TARGET_EFAULT; + if (arg2 == 0 && arg3 == 0) { + /* Special-case NULL buffer and zero length, which should succeed */ + p = 0; + } else { + p = lock_user(VERIFY_WRITE, arg2, arg3, 0); + if (!p) { + return -TARGET_EFAULT; + } + } ret = get_errno(pread64(arg1, p, arg3, target_offset64(arg4, arg5))); unlock_user(p, arg2, ret); return ret; @@ -9726,8 +9733,15 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, arg4 = arg5; arg5 = arg6; } - if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1))) - return -TARGET_EFAULT; + if (arg2 == 0 && arg3 == 0) { + /* Special-case NULL buffer and zero length, which should succeed */ + p = 0; + } else { + p = lock_user(VERIFY_READ, arg2, arg3, 1); + if (!p) { + return -TARGET_EFAULT; + } + } ret = get_errno(pwrite64(arg1, p, arg3, target_offset64(arg4, arg5))); unlock_user(p, arg2, 0); return ret; |