Hi all,

On Wed, 27 Oct 2021 21:09:24 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> 
> [I am not sure why this error only popped up after I merged Andrew's
> patch set ...]
> 
> After merging the btrfs tree, today's linux-next build (x86_64
> allmodconfig) failed like this:
> 
> In file included from include/linux/string.h:253,
>                  from include/linux/bitmap.h:11,
>                  from include/linux/cpumask.h:12,
>                  from arch/x86/include/asm/cpumask.h:5,
>                  from arch/x86/include/asm/msr.h:11,
>                  from arch/x86/include/asm/processor.h:22,
>                  from arch/x86/include/asm/cpufeature.h:5,
>                  from arch/x86/include/asm/thread_info.h:53,
>                  from include/linux/thread_info.h:60,
>                  from arch/x86/include/asm/preempt.h:7,
>                  from include/linux/preempt.h:78,
>                  from include/linux/spinlock.h:55,
>                  from include/linux/wait.h:9,
>                  from include/linux/mempool.h:8,
>                  from include/linux/bio.h:8,
>                  from fs/btrfs/ioctl.c:7:
> In function 'memcpy',
>     inlined from '_btrfs_ioctl_send' at fs/btrfs/ioctl.c:4846:3:
> include/linux/fortify-string.h:219:4: error: call to '__write_overflow' declared with attribute error: detected write beyond size of object (1st parameter)
>   219 |    __write_overflow();
>       |    ^~~~~~~~~~~~~~~~~~
> 
> Caused by commit
> 
>   c8d9cdfc766d ("btrfs: send: prepare for v2 protocol")
> 
> This changes the "reserved" field of struct btrfs_ioctl_send_args from 4 u64's to 3, but the above memcpy is copying the "reserved" filed from a struct btrfs_ioctl_send_args_32 (4 u64s) into it.
> 
> All I could really do at this point was mark BTRFS_FS as BROKEN
> (TEST_KMOD selects BTRFS_FS):
> 
> From: Stephen Rothwell <sfr@canb.auug.org.au>
> Date: Wed, 27 Oct 2021 20:53:24 +1100
> Subject: [PATCH] make btrfs as BROKEN due to an inconsistent API change
> 
> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
> ---
>  fs/btrfs/Kconfig  | 1 +
>  lib/Kconfig.debug | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/fs/btrfs/Kconfig b/fs/btrfs/Kconfig
> index 520a0f6a7d9e..f7dd994a88af 100644
> --- a/fs/btrfs/Kconfig
> +++ b/fs/btrfs/Kconfig
> @@ -20,6 +20,7 @@ config BTRFS_FS
>  	select SRCU
>  	depends on !PPC_256K_PAGES	# powerpc
>  	depends on !PAGE_SIZE_256KB	# hexagon
> +	depends on BROKEN
>  
>  	help
>  	  Btrfs is a general purpose copy-on-write filesystem with extents,
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 0104cafd403f..44a6df361016 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2491,6 +2491,7 @@ config TEST_KMOD
>  	depends on m
>  	depends on NETDEVICES && NET_CORE && INET # for TUN
>  	depends on BLOCK
> +	depends on BROKEN
>  	select TEST_LKM
>  	select XFS_FS
>  	select TUN
> -- 
> 2.33.0

Ping?

-- 
Cheers,
Stephen Rothwell