@@ -7930,18 +7930,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
ret = 0; /* avoid warning */
break;
case TARGET_NR_read:
- if (arg3 == 0)
- ret = 0;
- else {
- if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
- goto efault;
- ret = get_errno(safe_read(arg1, p, arg3));
- if (ret >= 0 &&
- fd_trans_host_to_target_data(arg1)) {
- ret = fd_trans_host_to_target_data(arg1)(p, ret);
- }
- unlock_user(p, arg2, ret);
+ if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
+ goto efault;
+ ret = get_errno(safe_read(arg1, p, arg3));
+ if (ret >= 0 &&
+ fd_trans_host_to_target_data(arg1)) {
+ ret = fd_trans_host_to_target_data(arg1)(p, ret);
}
+ unlock_user(p, arg2, ret);
break;
case TARGET_NR_write:
if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
A zero-length read still needs to do the usual checks, thus it may return errors like EBADF. Signed-off-by: Andreas Schwab <schwab@suse.de> --- linux-user/syscall.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-)