On Tue, 14 Mar 2023 10:10:42 +0800 kernel test robot <yujie.liu@xxxxxxxxx> wrote: > Greeting, > > Previous report: > https://lore.kernel.org/oe-lkp/202303100947.9b421b1c-yujie.liu@xxxxxxxxx > > FYI, we noticed BUG:kernel_NULL_pointer_dereference,address due to commit (built with gcc-11): > > commit: 480c454ff64b734a35677ee4b239e32143a4235c ("mm: return an ERR_PTR from __filemap_get_folio") > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master > > [test failed on linux-next/master 24469a0e5052ba01a35a15f104717a82b7a4798b] > > in testcase: trinity > version: trinity-x86_64-e63e4843-1_20220913 > with following parameters: > > runtime: 300s > group: group-04 > > test-description: Trinity is a linux system call fuzz tester. > test-url: http://codemonkey.org.uk/projects/trinity/ > > on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G > > caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): > > > [ 29.300153][ T6430] BUG: kernel NULL pointer dereference, address: 0000000000000000 Thanks, I expect this is fixed by commit 151dff099e8e6d9c8efcc75ad0ad3b8eead58704 Author: Christoph Hellwig <hch@xxxxxx> Date: Fri Mar 10 08:00:23 2023 +0100 mm-return-an-err_ptr-from-__filemap_get_folio-fix fix null-pointer deref Link: https://lkml.kernel.org/r/20230310070023.GA13563@xxxxxx Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reported-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxxxx> Link: https://lkml.kernel.org/r/20230310043137.GA1624890@u2004 Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> diff --git a/mm/swap_state.c b/mm/swap_state.c index c7160070b9da..b76a65ac28b3 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -390,6 +390,8 @@ struct folio *filemap_get_incore_folio(struct address_space *mapping, struct swap_info_struct *si; struct folio *folio = filemap_get_entry(mapping, index); + if (!folio) + return ERR_PTR(-ENOENT); if (!xa_is_value(folio)) return folio; if (!shmem_mapping(mapping))
