[Qemu-devel] linux-user: fix getcwd syscall

[Qemu-devel] linux-user: fix getcwd syscall

[Arnaud Patard]

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The patch called "prefer glibc over direct syscalls" (commit 7118) has
replaced the getcwd syscall with a call to the glibc. With this change,
the syscall is returning -1 in error case and 0 otherwise.
This is problematic as the sys_getcwd syscall should return the number
of bytes written to the buffer including the '\0'.

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
---

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diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 74b41a8..f5875aa 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -293,7 +293,7 @@ static int sys_getcwd1(char *buf, size_t size)
       /* getcwd() sets errno */
       return (-1);
   }
-  return (0);
+  return strlen(buf)+1;
 }
 
 #ifdef CONFIG_ATFILE

Re: [Qemu-devel] linux-user: fix getcwd syscall

[Riku Voipio]

Hi,

You are right. This is what I get for only checking the manpage.

Acked-By: Riku Voipio <riku.voipio@iki.fi>

On Thu, Apr 16, 2009 at 03:04:23PM +0200, Arnaud Patard wrote:
> 
> The patch called "prefer glibc over direct syscalls" (commit 7118) has
> replaced the getcwd syscall with a call to the glibc. With this change,
> the syscall is returning -1 in error case and 0 otherwise.
> This is problematic as the sys_getcwd syscall should return the number
> of bytes written to the buffer including the '\0'.
> 
> Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
> ---

> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 74b41a8..f5875aa 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -293,7 +293,7 @@ static int sys_getcwd1(char *buf, size_t size)
>        /* getcwd() sets errno */
>        return (-1);
>    }
> -  return (0);
> +  return strlen(buf)+1;
>  }
>  
>  #ifdef CONFIG_ATFILE


-- 
"rm -rf" only sounds scary if you don't have backups

Re: [Qemu-devel] linux-user: fix getcwd syscall

[Aurelien Jarno]

On Thu, Apr 16, 2009 at 03:04:23PM +0200, Arnaud Patard wrote:
> 
> The patch called "prefer glibc over direct syscalls" (commit 7118) has
> replaced the getcwd syscall with a call to the glibc. With this change,
> the syscall is returning -1 in error case and 0 otherwise.
> This is problematic as the sys_getcwd syscall should return the number
> of bytes written to the buffer including the '\0'.
> 
> Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
> ---

Thanks, applied.

> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 74b41a8..f5875aa 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -293,7 +293,7 @@ static int sys_getcwd1(char *buf, size_t size)
>        /* getcwd() sets errno */
>        return (-1);
>    }
> -  return (0);
> +  return strlen(buf)+1;
>  }
>  
>  #ifdef CONFIG_ATFILE


-- 
Aurelien Jarno	                        GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net