[PATCH 0/2] tests/qtest: Avoid char arrays in more Arm tests

[PATCH 0/2] tests/qtest: Avoid char arrays in more Arm tests

[Peter Maydell]

This patchset fixes a couple more -Wformat-overflow=2 warnings with
gcc 7.5.0. Same issue as this other series I just posted, but two
different files:

https://lore.kernel.org/qemu-devel/20260310151507.2973843-1-peter.maydell@linaro.org/

Since there's no dependency between the two sets of patches I sent
this out as a separate series rather than a v2 with those others
folded in.

thanks
-- PMM

Peter Maydell (2):
  tests/qtest/ast2700-gpio-test: Use g_strdup_printf() instead of char
    arrays
  tests/qtest/aspeed_gpio-test: Use g_strdup_printf() instead of char
    arrays

 tests/qtest/aspeed_gpio-test.c  | 4 ++--
 tests/qtest/ast2700-gpio-test.c | 3 +--
 2 files changed, 3 insertions(+), 4 deletions(-)

-- 
2.43.0

[PATCH 1/2] tests/qtest/ast2700-gpio-test: Use g_strdup_printf() instead of char arrays

[Peter Maydell]

Older versions of gcc with -Wformat-overflow=2 don't like the usage of
fixed size char arrays in this test; gcc 7.5.0 (SUSE Linux) says:

../tests/qtest/ast2700-gpio-test.c: In function ‘test_input_pins’:
../tests/qtest/ast2700-gpio-test.c:54:36: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
             sprintf(name, "gpio%c%d", c, i);
                                    ^
../tests/qtest/ast2700-gpio-test.c:54:13: note: ‘sprintf’ output between 7 and 17 bytes into a destination of size 16
             sprintf(name, "gpio%c%d", c, i);
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This can't actually happen because of the limited size of the values
being substituted in.  However rather than require readers to check
whether the arrays really have been declared large enough, we prefer
to use g_strdup_printf() for this kind of string work.

Reported-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 tests/qtest/ast2700-gpio-test.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tests/qtest/ast2700-gpio-test.c b/tests/qtest/ast2700-gpio-test.c
index eeae9bf11f..533feea7da 100644
--- a/tests/qtest/ast2700-gpio-test.c
+++ b/tests/qtest/ast2700-gpio-test.c
@@ -44,14 +44,13 @@ static void test_output_pins(const char *machine, const uint32_t base)
 static void test_input_pins(const char *machine, const uint32_t base)
 {
     QTestState *s = qtest_init(machine);
-    char name[16];
     uint32_t offset = 0;
     uint32_t value = 0;
     uint32_t pin = 0;
 
     for (char c = 'A'; c <= 'D'; c++) {
         for (int i = 0; i < 8; i++) {
-            sprintf(name, "gpio%c%d", c, i);
+            g_autofree const char *name = g_strdup_printf("gpio%c%d", c, i);
             offset = base + (pin * 4);
             /* input direction */
             qtest_writel(s, offset, 0);
-- 
2.43.0

Re: [PATCH 1/2] tests/qtest/ast2700-gpio-test: Use g_strdup_printf() instead of char arrays

[Philippe Mathieu-Daudé]

On 10/3/26 16:33, Peter Maydell wrote:
> Older versions of gcc with -Wformat-overflow=2 don't like the usage of
> fixed size char arrays in this test; gcc 7.5.0 (SUSE Linux) says:
> 
> ../tests/qtest/ast2700-gpio-test.c: In function ‘test_input_pins’:
> ../tests/qtest/ast2700-gpio-test.c:54:36: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
>               sprintf(name, "gpio%c%d", c, i);
>                                      ^
> ../tests/qtest/ast2700-gpio-test.c:54:13: note: ‘sprintf’ output between 7 and 17 bytes into a destination of size 16
>               sprintf(name, "gpio%c%d", c, i);
>               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> This can't actually happen because of the limited size of the values
> being substituted in.  However rather than require readers to check
> whether the arrays really have been declared large enough, we prefer
> to use g_strdup_printf() for this kind of string work.
> 
> Reported-by: Fabiano Rosas <farosas@suse.de>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>   tests/qtest/ast2700-gpio-test.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

[PATCH 2/2] tests/qtest/aspeed_gpio-test: Use g_strdup_printf() instead of char arrays

[Peter Maydell]

Older versions of gcc with -Wformat-overflow=2 don't like the usage of
fixed size char arrays in this test; gcc 7.5.0 (SUSE Linux) says:

../tests/qtest/aspeed_gpio-test.c: In function ‘test_set_input_pins’:
../tests/qtest/aspeed_gpio-test.c:149:36: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
             sprintf(name, "gpio%c%d", c, i);
                                    ^
../tests/qtest/aspeed_gpio-test.c:149:13: note: ‘sprintf’ output between 7 and 17 bytes into a destination of size 16
             sprintf(name, "gpio%c%d", c, i);
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This can't actually happen because of the limited size of the values
being substituted in.  However rather than require readers to check
whether the arrays really have been declared large enough, we prefer
to use g_strdup_printf() for this kind of string work.

Reported-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 tests/qtest/aspeed_gpio-test.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/qtest/aspeed_gpio-test.c b/tests/qtest/aspeed_gpio-test.c
index decbba23c8..029b3731d1 100644
--- a/tests/qtest/aspeed_gpio-test.c
+++ b/tests/qtest/aspeed_gpio-test.c
@@ -140,13 +140,13 @@ static void test_set_colocated_pins(const void *data)
 static void test_set_input_pins(const void *data)
 {
     QTestState *s = (QTestState *)data;
-    char name[16];
     uint32_t value;
 
     qtest_writel(s, AST2600_GPIO_BASE + GPIO_ABCD_DIRECTION, 0x00000000);
     for (char c = 'A'; c <= 'D'; c++) {
         for (int i = 0; i < 8; i++) {
-            sprintf(name, "gpio%c%d", c, i);
+            g_autofree const char *name = g_strdup_printf("gpio%c%d", c, i);
+
             qtest_qom_set_bool(s, "/machine/soc/gpio", name, true);
         }
     }
-- 
2.43.0

Re: [PATCH 2/2] tests/qtest/aspeed_gpio-test: Use g_strdup_printf() instead of char arrays

[Philippe Mathieu-Daudé]

On 10/3/26 16:33, Peter Maydell wrote:
> Older versions of gcc with -Wformat-overflow=2 don't like the usage of
> fixed size char arrays in this test; gcc 7.5.0 (SUSE Linux) says:
> 
> ../tests/qtest/aspeed_gpio-test.c: In function ‘test_set_input_pins’:
> ../tests/qtest/aspeed_gpio-test.c:149:36: error: ‘sprintf’ may write a terminating nul past the end of the destination [-Werror=format-overflow=]
>               sprintf(name, "gpio%c%d", c, i);
>                                      ^
> ../tests/qtest/aspeed_gpio-test.c:149:13: note: ‘sprintf’ output between 7 and 17 bytes into a destination of size 16
>               sprintf(name, "gpio%c%d", c, i);
>               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> This can't actually happen because of the limited size of the values
> being substituted in.  However rather than require readers to check
> whether the arrays really have been declared large enough, we prefer
> to use g_strdup_printf() for this kind of string work.
> 
> Reported-by: Fabiano Rosas <farosas@suse.de>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>   tests/qtest/aspeed_gpio-test.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

Re: [PATCH 0/2] tests/qtest: Avoid char arrays in more Arm tests

[Fabiano Rosas]

Peter Maydell <peter.maydell@linaro.org> writes:

> This patchset fixes a couple more -Wformat-overflow=2 warnings with
> gcc 7.5.0. Same issue as this other series I just posted, but two
> different files:
>
> https://lore.kernel.org/qemu-devel/20260310151507.2973843-1-peter.maydell@linaro.org/
>
> Since there's no dependency between the two sets of patches I sent
> this out as a separate series rather than a v2 with those others
> folded in.
>
> thanks
> -- PMM
>
> Peter Maydell (2):
>   tests/qtest/ast2700-gpio-test: Use g_strdup_printf() instead of char
>     arrays
>   tests/qtest/aspeed_gpio-test: Use g_strdup_printf() instead of char
>     arrays
>
>  tests/qtest/aspeed_gpio-test.c  | 4 ++--
>  tests/qtest/ast2700-gpio-test.c | 3 +--
>  2 files changed, 3 insertions(+), 4 deletions(-)

Series:

Tested-by: Fabiano Rosas <farosas@suse.de>