[PATCH] pru: Fix memory corruption on syscall return

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[PATCH] pru: Fix memory corruption on syscall return

Dimitar Dimitrov
In the initial code I missed one level of pointer indirection. Instead
of storing errno in impure_data, _impure_ptr was corrupted.

Only simulator is impacted. Real targets have no OS and no syscalls.

This resolves a bunch of stdio cases from the GCC testsuite:
  FAIL->PASS: gcc.c-torture/execute/printf-2.c   -O0  execution test

Signed-off-by: Dimitar Dimitrov <[hidden email]>
---
 libgloss/pru/syscalls.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libgloss/pru/syscalls.S b/libgloss/pru/syscalls.S
index 8ed7601a4..3ad0d9215 100644
--- a/libgloss/pru/syscalls.S
+++ b/libgloss/pru/syscalls.S
@@ -42,6 +42,7 @@ __SC_ret:
  /* Invert return code and store to errno (first int in _impure_ptr).  */
  rsb r14, r14, 0
  ldi32 r1, _impure_ptr
+ lbbo r1, r1, 0, 4
  sbbo r14, r1, 0, 4
  /* Return -1 (for both int32_t or int64_t).  */
  fill r14, 8
--
2.20.1

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Re: [PATCH] pru: Fix memory corruption on syscall return

Dimitar Dimitrov
On сряда, 3 юни 2020 г. 19:14:22 EEST Dimitar Dimitrov wrote:

> In the initial code I missed one level of pointer indirection. Instead
> of storing errno in impure_data, _impure_ptr was corrupted.
>
> Only simulator is impacted. Real targets have no OS and no syscalls.
>
> This resolves a bunch of stdio cases from the GCC testsuite:
>   FAIL->PASS: gcc.c-torture/execute/printf-2.c   -O0  execution test
>
> Signed-off-by: Dimitar Dimitrov <[hidden email]>
> ---
>  libgloss/pru/syscalls.S | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/libgloss/pru/syscalls.S b/libgloss/pru/syscalls.S
> index 8ed7601a4..3ad0d9215 100644
> --- a/libgloss/pru/syscalls.S
> +++ b/libgloss/pru/syscalls.S
> @@ -42,6 +42,7 @@ __SC_ret:
>   /* Invert return code and store to errno (first int in _impure_ptr).  */
>   rsb r14, r14, 0
>   ldi32 r1, _impure_ptr
> + lbbo r1, r1, 0, 4
>   sbbo r14, r1, 0, 4
>   /* Return -1 (for both int32_t or int64_t).  */
>   fill r14, 8

Gentle ping



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Re: [PATCH] pru: Fix memory corruption on syscall return

Sourceware - newlib list mailing list
In reply to this post by Dimitar Dimitrov
On Jun  3 19:14, Dimitar Dimitrov wrote:

> In the initial code I missed one level of pointer indirection. Instead
> of storing errno in impure_data, _impure_ptr was corrupted.
>
> Only simulator is impacted. Real targets have no OS and no syscalls.
>
> This resolves a bunch of stdio cases from the GCC testsuite:
>   FAIL->PASS: gcc.c-torture/execute/printf-2.c   -O0  execution test
>
> Signed-off-by: Dimitar Dimitrov <[hidden email]>
> ---
>  libgloss/pru/syscalls.S | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/libgloss/pru/syscalls.S b/libgloss/pru/syscalls.S
> index 8ed7601a4..3ad0d9215 100644
> --- a/libgloss/pru/syscalls.S
> +++ b/libgloss/pru/syscalls.S
> @@ -42,6 +42,7 @@ __SC_ret:
>   /* Invert return code and store to errno (first int in _impure_ptr).  */
>   rsb r14, r14, 0
>   ldi32 r1, _impure_ptr
> + lbbo r1, r1, 0, 4
>   sbbo r14, r1, 0, 4
>   /* Return -1 (for both int32_t or int64_t).  */
>   fill r14, 8
> --
> 2.20.1

Pushed.


Thanks,
Corinna

--
Corinna Vinschen
Cygwin Maintainer
Red Hat