On Sun 01-11-20 06:09:58, Rustam Kovhaev wrote: > when directory item has an invalid value set for ih_entry_count it might > trigger use-after-free or out-of-bounds read in bin_search_in_dir_item() > > ih_entry_count * IH_SIZE for directory item should not be larger than > ih_item_len > > Reported-and-tested-by: syzbot+83b6f7cf9922cae5c4d7@xxxxxxxxxxxxxxxxxxxxxxxxx > Link: https://syzkaller.appspot.com/bug?extid=83b6f7cf9922cae5c4d7 > Signed-off-by: Rustam Kovhaev <rkovhaev@xxxxxxxxx> Thanks! I've added the patch to my tree and will push it to Linus. Honza > --- > fs/reiserfs/stree.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c > index 8bf88d690729..476a7ff49482 100644 > --- a/fs/reiserfs/stree.c > +++ b/fs/reiserfs/stree.c > @@ -454,6 +454,12 @@ static int is_leaf(char *buf, int blocksize, struct buffer_head *bh) > "(second one): %h", ih); > return 0; > } > + if (is_direntry_le_ih(ih) && (ih_item_len(ih) < (ih_entry_count(ih) * IH_SIZE))) { > + reiserfs_warning(NULL, "reiserfs-5093", > + "item entry count seems wrong %h", > + ih); > + return 0; > + } > prev_location = ih_location(ih); > } > > -- > 2.28.0 > -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
