Zero-length arrays are deprecated[1]. Replace struct ethtool_rxnfc's
"rule_locs" 0-length array with a flexible array. Detected with GCC 13,
using -fstrict-flex-arrays=3:
In file included from include/asm-generic/memory_model.h:5,
from arch/x86/include/asm/page.h:86,
from arch/x86/include/asm/thread_info.h:12,
from include/linux/thread_info.h:60,
from arch/x86/include/asm/preempt.h:9,
from include/linux/preempt.h:78,
from include/linux/spinlock.h:56,
from include/linux/mmzone.h:8,
from include/linux/gfp.h:7,
from include/linux/mm.h:7,
from mm/sparse-vmemmap.c:21:
In function 'reuse_compound_section',
inlined from 'vmemmap_populate_compound_pages' at mm/sparse-vmemmap.c:407:6,
inlined from '__populate_section_memmap' at mm/sparse-vmemmap.c:463:7:
mm/sparse-vmemmap.c:376:39: warning: array subscript <unknown> is outside array bounds of 'struct range[0]' [-Warray-bounds=]
376 | PHYS_PFN(pgmap->ranges[pgmap->nr_range].start);
| ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
include/linux/pfn.h:22:43: note: in definition of macro 'PHYS_PFN'
22 | #define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT))
| ^
In file included from include/linux/mm.h:31:
include/linux/memremap.h: In function '__populate_section_memmap':
include/linux/memremap.h:138:30: note: while referencing 'ranges'
138 | struct range ranges[0];
| ^~~~~~
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays
Cc: Andrew Morton <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Alex Sierra <[email protected]>
Cc: Felix Kuehling <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: Shiyang Ruan <[email protected]>
Cc: "Gustavo A. R. Silva" <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
include/linux/memremap.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index 7fcaf3180a5b..1314d9c5f05b 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -135,7 +135,7 @@ struct dev_pagemap {
int nr_range;
union {
struct range range;
- struct range ranges[0];
+ DECLARE_FLEX_ARRAY(struct range, ranges);
};
};
--
2.34.1
I think this is the same patch:
https://lore.kernel.org/linux-hardening/YxKO%2FjY1x0xTpl4r@work/
It's actually in linux-next.
--
Gustavo
On Thu, Jan 05, 2023 at 02:01:53PM -0800, Kees Cook wrote:
> Zero-length arrays are deprecated[1]. Replace struct ethtool_rxnfc's
> "rule_locs" 0-length array with a flexible array. Detected with GCC 13,
> using -fstrict-flex-arrays=3:
>
> In file included from include/asm-generic/memory_model.h:5,
> from arch/x86/include/asm/page.h:86,
> from arch/x86/include/asm/thread_info.h:12,
> from include/linux/thread_info.h:60,
> from arch/x86/include/asm/preempt.h:9,
> from include/linux/preempt.h:78,
> from include/linux/spinlock.h:56,
> from include/linux/mmzone.h:8,
> from include/linux/gfp.h:7,
> from include/linux/mm.h:7,
> from mm/sparse-vmemmap.c:21:
> In function 'reuse_compound_section',
> inlined from 'vmemmap_populate_compound_pages' at mm/sparse-vmemmap.c:407:6,
> inlined from '__populate_section_memmap' at mm/sparse-vmemmap.c:463:7:
> mm/sparse-vmemmap.c:376:39: warning: array subscript <unknown> is outside array bounds of 'struct range[0]' [-Warray-bounds=]
> 376 | PHYS_PFN(pgmap->ranges[pgmap->nr_range].start);
> | ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
> include/linux/pfn.h:22:43: note: in definition of macro 'PHYS_PFN'
> 22 | #define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT))
> | ^
> In file included from include/linux/mm.h:31:
> include/linux/memremap.h: In function '__populate_section_memmap':
> include/linux/memremap.h:138:30: note: while referencing 'ranges'
> 138 | struct range ranges[0];
> | ^~~~~~
>
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays
>
> Cc: Andrew Morton <[email protected]>
> Cc: Dan Williams <[email protected]>
> Cc: Alex Sierra <[email protected]>
> Cc: Felix Kuehling <[email protected]>
> Cc: "Matthew Wilcox (Oracle)" <[email protected]>
> Cc: Shiyang Ruan <[email protected]>
> Cc: "Gustavo A. R. Silva" <[email protected]>
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> ---
> include/linux/memremap.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/memremap.h b/include/linux/memremap.h
> index 7fcaf3180a5b..1314d9c5f05b 100644
> --- a/include/linux/memremap.h
> +++ b/include/linux/memremap.h
> @@ -135,7 +135,7 @@ struct dev_pagemap {
> int nr_range;
> union {
> struct range range;
> - struct range ranges[0];
> + DECLARE_FLEX_ARRAY(struct range, ranges);
> };
> };
>
> --
> 2.34.1
>
Kees Cook wrote:
> Zero-length arrays are deprecated[1]. Replace struct ethtool_rxnfc's
> "rule_locs" 0-length array with a flexible array. Detected with GCC 13,
> using -fstrict-flex-arrays=3:
>
> In file included from include/asm-generic/memory_model.h:5,
> from arch/x86/include/asm/page.h:86,
> from arch/x86/include/asm/thread_info.h:12,
> from include/linux/thread_info.h:60,
> from arch/x86/include/asm/preempt.h:9,
> from include/linux/preempt.h:78,
> from include/linux/spinlock.h:56,
> from include/linux/mmzone.h:8,
> from include/linux/gfp.h:7,
> from include/linux/mm.h:7,
> from mm/sparse-vmemmap.c:21:
> In function 'reuse_compound_section',
> inlined from 'vmemmap_populate_compound_pages' at mm/sparse-vmemmap.c:407:6,
> inlined from '__populate_section_memmap' at mm/sparse-vmemmap.c:463:7:
> mm/sparse-vmemmap.c:376:39: warning: array subscript <unknown> is outside array bounds of 'struct range[0]' [-Warray-bounds=]
> 376 | PHYS_PFN(pgmap->ranges[pgmap->nr_range].start);
> | ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
> include/linux/pfn.h:22:43: note: in definition of macro 'PHYS_PFN'
> 22 | #define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT))
> | ^
> In file included from include/linux/mm.h:31:
> include/linux/memremap.h: In function '__populate_section_memmap':
> include/linux/memremap.h:138:30: note: while referencing 'ranges'
> 138 | struct range ranges[0];
> | ^~~~~~
>
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays
>
> Cc: Andrew Morton <[email protected]>
> Cc: Dan Williams <[email protected]>
> Cc: Alex Sierra <[email protected]>
> Cc: Felix Kuehling <[email protected]>
> Cc: "Matthew Wilcox (Oracle)" <[email protected]>
> Cc: Shiyang Ruan <[email protected]>
> Cc: "Gustavo A. R. Silva" <[email protected]>
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
Looks good to me:
Reviewed-by: Dan Williams <[email protected]>
> ---
> include/linux/memremap.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/memremap.h b/include/linux/memremap.h
> index 7fcaf3180a5b..1314d9c5f05b 100644
> --- a/include/linux/memremap.h
> +++ b/include/linux/memremap.h
> @@ -135,7 +135,7 @@ struct dev_pagemap {
> int nr_range;
> union {
> struct range range;
> - struct range ranges[0];
> + DECLARE_FLEX_ARRAY(struct range, ranges);
> };
> };
>
> --
> 2.34.1
>
On Thu, Jan 05, 2023 at 04:14:05PM -0600, Gustavo A. R. Silva wrote:
> I think this is the same patch:
>
> https://lore.kernel.org/linux-hardening/YxKO%2FjY1x0xTpl4r@work/
>
> It's actually in linux-next.
Ah-ha! Thank you! I'll move to linux-next for build testing.
--
Kees Cook
On Thu, Jan 05, 2023 at 04:14:05PM -0600, Gustavo A. R. Silva wrote:
> I think this is the same patch:
>
> https://lore.kernel.org/linux-hardening/YxKO%2FjY1x0xTpl4r@work/
>
> It's actually in linux-next.
Hm, it's been in -next since September? Is this in a tree of yours that
didn't get pulled for v6.2?
--
Kees Cook
On Thu, Jan 05, 2023 at 05:14:23PM -0600, Gustavo A. R. Silva wrote:
>
>
> On 1/5/23 16:41, Kees Cook wrote:
> > On Thu, Jan 05, 2023 at 04:14:05PM -0600, Gustavo A. R. Silva wrote:
> > > I think this is the same patch:
> > >
> > > https://lore.kernel.org/linux-hardening/YxKO%2FjY1x0xTpl4r@work/
> > >
> > > It's actually in linux-next.
> >
> > Hm, it's been in -next since September? Is this in a tree of yours that
> > didn't get pulled for v6.2?
>
> No. I didn't send it. It's just one of the two patches I have in my -next
> tree. They didn't look like high priority at the time.
Cool. I'd like to get -fstrict-flex-arrays=3 finished this devel cycle,
if possible. Can you add this one too?
https://lore.kernel.org/lkml/YzIc8z+QaHvqPjLX@work
I don't see it in patchwork which I find confusing too. :P
--
Kees Cook
On Thu, Jan 05, 2023 at 03:37:03PM -0800, Kees Cook wrote:
> On Thu, Jan 05, 2023 at 05:14:23PM -0600, Gustavo A. R. Silva wrote:
> >
> >
> > On 1/5/23 16:41, Kees Cook wrote:
> > > On Thu, Jan 05, 2023 at 04:14:05PM -0600, Gustavo A. R. Silva wrote:
> > > > I think this is the same patch:
> > > >
> > > > https://lore.kernel.org/linux-hardening/YxKO%2FjY1x0xTpl4r@work/
> > > >
> > > > It's actually in linux-next.
> > >
> > > Hm, it's been in -next since September? Is this in a tree of yours that
> > > didn't get pulled for v6.2?
> >
> > No. I didn't send it. It's just one of the two patches I have in my -next
> > tree. They didn't look like high priority at the time.
>
> Cool. I'd like to get -fstrict-flex-arrays=3 finished this devel cycle,
> if possible. Can you add this one too?
>
> https://lore.kernel.org/lkml/YzIc8z+QaHvqPjLX@work
Done!
https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/log/?h=for-next/kspp
>
> I don't see it in patchwork which I find confusing too. :P
mmh... and I don't remember updating it in patchwork before.
(thinkingface)
--
Gustavo
On 1/5/23 16:41, Kees Cook wrote:
> On Thu, Jan 05, 2023 at 04:14:05PM -0600, Gustavo A. R. Silva wrote:
>> I think this is the same patch:
>>
>> https://lore.kernel.org/linux-hardening/YxKO%2FjY1x0xTpl4r@work/
>>
>> It's actually in linux-next.
>
> Hm, it's been in -next since September? Is this in a tree of yours that
> didn't get pulled for v6.2?
No. I didn't send it. It's just one of the two patches I have in my -next
tree. They didn't look like high priority at the time.
--
Gustavo