This is a note to let you know that I've just added the patch titled
btrfs: avoid overflow when sector_t is 32 bit
to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
btrfs-avoid-overflow-when-sector_t-is-32-bit.patch
and it can be found in the queue-4.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 2d8ce70a08fe033c904115d59276ad86adeaa337 Mon Sep 17 00:00:00 2001
From: Goffredo Baroncelli <kreijack@xxxxxxxxx>
Date: Tue, 3 Oct 2017 19:31:10 +0200
Subject: btrfs: avoid overflow when sector_t is 32 bit
From: Goffredo Baroncelli <kreijack@xxxxxxxxx>
commit 2d8ce70a08fe033c904115d59276ad86adeaa337 upstream.
Jean-Denis Girard noticed commit c821e7f3 "pass bytes to
btrfs_bio_alloc" (https://patchwork.kernel.org/patch/9763081/)
introduces a regression on 32 bit machines.
When CONFIG_LBDAF is _not_ defined (CONFIG_LBDAF == Support for large
(2TB+) block devices and files) sector_t is 32 bit on 32bit machines.
In the function submit_extent_page, 'sector' (which is sector_t type) is
multiplied by 512 to convert it from sectors to bytes, leading to an
overflow when the disk is bigger than 4GB (!).
I added a cast to u64 to avoid overflow.
Fixes: c821e7f3 ("btrfs: pass bytes to btrfs_bio_alloc")
Signed-off-by: Goffredo Baroncelli <kreijack@xxxxxxxxx>
Tested-by: Jean-Denis Girard <jd.girard@xxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/extent_io.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2799,7 +2799,7 @@ static int submit_extent_page(int op, in
}
}
- bio = btrfs_bio_alloc(bdev, sector << 9);
+ bio = btrfs_bio_alloc(bdev, (u64)sector << 9);
bio_add_page(bio, page, page_size, offset);
bio->bi_end_io = end_io_func;
bio->bi_private = tree;
Patches currently in stable-queue which might be from kreijack@xxxxxxxxx are
queue-4.13/btrfs-avoid-overflow-when-sector_t-is-32-bit.patch