Re: [PATCH 5.15] jfs: Fix shift-out-of-bounds in dbDiscardAG

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Dec 13, 2024 at 01:43:50PM +0800, guocai.he.cn@windriver.com wrote:
> From: Pei Li <peili.dev@gmail.com>
> 
> [ Upstream commit 7063b80268e2593e58bee8a8d709c2f3ff93e2f2 ]
> 
> When searching for the next smaller log2 block, BLKSTOL2() returned 0,
> causing shift exponent -1 to be negative.
> 
> This patch fixes the issue by exiting the loop directly when negative
> shift is found.
> 
> Reported-by: syzbot+61be3359d2ee3467e7e4@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=61be3359d2ee3467e7e4
> Signed-off-by: Pei Li <peili.dev@gmail.com>
> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
> Signed-off-by: Guocai He <guocai.he.cn@windriver.com>
> ---
>  fs/jfs/jfs_dmap.c | 2 ++
>  1 file changed, 2 insertions(+)


Now deleted, please see:
        https://lore.kernel.org/r/2024121322-conjuror-gap-b542@gregkh
for what you all need to do, TOGETHER, to get this fixed and so that I
can accept patches from your company in the future.

thanks,

greg k-h