linux-user/flatload.c: Fix setting of image_info::end_code

[PATCH for-7.1] linux-user/flatload.c: Fix setting of image_info::end_code

Posted by Peter Maydell 1 year, 9 months ago

The flatload loader sets the end_code field in the image_info struct
incorrectly, due to a typo.

This is a very long-standing bug (dating all the way back to when
the bFLT loader was added in 2006), but has gone unnoticed because
(a) most people don't use bFLT binaries
(b) we don't actually do anything with the end_code field, except
    print it in debugging traces and pass it to TCG plugins

Fix the typo.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1119
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 linux-user/flatload.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/linux-user/flatload.c b/linux-user/flatload.c
index e4c2f89a226..e99570ca182 100644
--- a/linux-user/flatload.c
+++ b/linux-user/flatload.c
@@ -808,7 +808,7 @@ int load_flt_binary(struct linux_binprm *bprm, struct image_info *info)
 
     /* Stash our initial stack pointer into the mm structure */
     info->start_code = libinfo[0].start_code;
-    info->end_code = libinfo[0].start_code = libinfo[0].text_len;
+    info->end_code = libinfo[0].start_code + libinfo[0].text_len;
     info->start_data = libinfo[0].start_data;
     info->end_data = libinfo[0].end_data;
     info->start_brk = libinfo[0].start_brk;
-- 
2.25.1

Re: [PATCH for-7.1] linux-user/flatload.c: Fix setting of image_info::end_code

Posted by Laurent Vivier 1 year, 9 months ago

Le 28/07/2022 à 17:14, Peter Maydell a écrit :
> The flatload loader sets the end_code field in the image_info struct
> incorrectly, due to a typo.
> 
> This is a very long-standing bug (dating all the way back to when
> the bFLT loader was added in 2006), but has gone unnoticed because
> (a) most people don't use bFLT binaries
> (b) we don't actually do anything with the end_code field, except
>      print it in debugging traces and pass it to TCG plugins
> 
> Fix the typo.
> 
> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1119
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>   linux-user/flatload.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/linux-user/flatload.c b/linux-user/flatload.c
> index e4c2f89a226..e99570ca182 100644
> --- a/linux-user/flatload.c
> +++ b/linux-user/flatload.c
> @@ -808,7 +808,7 @@ int load_flt_binary(struct linux_binprm *bprm, struct image_info *info)
>   
>       /* Stash our initial stack pointer into the mm structure */
>       info->start_code = libinfo[0].start_code;
> -    info->end_code = libinfo[0].start_code = libinfo[0].text_len;
> +    info->end_code = libinfo[0].start_code + libinfo[0].text_len;
>       info->start_data = libinfo[0].start_data;
>       info->end_data = libinfo[0].end_data;
>       info->start_brk = libinfo[0].start_brk;

Applied to my linux-user-for-7.1 branch.

Thanks,
Laurent

Re: [PATCH for-7.1] linux-user/flatload.c: Fix setting of image_info::end_code

Posted by Richard Henderson 1 year, 9 months ago

On 7/28/22 08:14, Peter Maydell wrote:
> The flatload loader sets the end_code field in the image_info struct
> incorrectly, due to a typo.
> 
> This is a very long-standing bug (dating all the way back to when
> the bFLT loader was added in 2006), but has gone unnoticed because
> (a) most people don't use bFLT binaries
> (b) we don't actually do anything with the end_code field, except
>      print it in debugging traces and pass it to TCG plugins
> 
> Fix the typo.
> 
> Resolves:https://gitlab.com/qemu-project/qemu/-/issues/1119
> Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
> ---
>   linux-user/flatload.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~