Patchwork linux-user: Fix unlock_user() call in return from poll()

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Submitter Peter Maydell
Date Feb. 25, 2011, 10:27 a.m.
Message ID <1298629660-23901-1-git-send-email-peter.maydell@linaro.org>
Download mbox | patch
Permalink /patch/84532/
State New
Headers show

Comments

Peter Maydell - Feb. 25, 2011, 10:27 a.m.
Correct the broken attempt to calculate the third argument
to unlock_user() in the code path which unlocked the pollfd
array on return from poll() and ppoll() emulation. (This
only caused a problem if unlock_user() wasn't a no-op, eg
if DEBUG_REMAP is defined.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 linux-user/syscall.c |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)
Aurelien Jarno - March 22, 2011, 6:50 a.m.
On Fri, Feb 25, 2011 at 10:27:40AM +0000, Peter Maydell wrote:
> Correct the broken attempt to calculate the third argument
> to unlock_user() in the code path which unlocked the pollfd
> array on return from poll() and ppoll() emulation. (This
> only caused a problem if unlock_user() wasn't a no-op, eg
> if DEBUG_REMAP is defined.)
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  linux-user/syscall.c |    4 +---
>  1 files changed, 1 insertions(+), 3 deletions(-)

Thanks, applied.

> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index cf8a4c3..822b863 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -6314,10 +6314,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
>                  for(i = 0; i < nfds; i++) {
>                      target_pfd[i].revents = tswap16(pfd[i].revents);
>                  }
> -                ret += nfds * (sizeof(struct target_pollfd)
> -                               - sizeof(struct pollfd));
>              }
> -            unlock_user(target_pfd, arg1, ret);
> +            unlock_user(target_pfd, arg1, sizeof(struct target_pollfd) * nfds);
>          }
>          break;
>  #endif
> -- 
> 1.7.1
> 
> 
>

Patch

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index cf8a4c3..822b863 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -6314,10 +6314,8 @@  abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
                 for(i = 0; i < nfds; i++) {
                     target_pfd[i].revents = tswap16(pfd[i].revents);
                 }
-                ret += nfds * (sizeof(struct target_pollfd)
-                               - sizeof(struct pollfd));
             }
-            unlock_user(target_pfd, arg1, ret);
+            unlock_user(target_pfd, arg1, sizeof(struct target_pollfd) * nfds);
         }
         break;
 #endif