The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a1fbc6750e212c5675a4e48d7f51d44607eb8756 Mon Sep 17 00:00:00 2001
From: "Matthew Wilcox (Oracle)" willy@infradead.org Date: Sun, 4 Oct 2020 19:04:26 +0100 Subject: [PATCH] btrfs: fix potential overflow in cluster_pages_for_defrag on 32bit arch
On 32-bit systems, this shift will overflow for files larger than 4GB as start_index is unsigned long while the calls to btrfs_delalloc_*_space expect u64.
CC: stable@vger.kernel.org # 4.4+ Fixes: df480633b891 ("btrfs: extent-tree: Switch to new delalloc space reserve and release") Reviewed-by: Josef Bacik josef@toxicpanda.com Signed-off-by: Matthew Wilcox (Oracle) willy@infradead.org Reviewed-by: David Sterba dsterba@suse.com [ define the variable instead of repeating the shift ] Signed-off-by: David Sterba dsterba@suse.com
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index ab408a23ba32..69a384145dc6 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1274,6 +1274,7 @@ static int cluster_pages_for_defrag(struct inode *inode, u64 page_start; u64 page_end; u64 page_cnt; + u64 start = (u64)start_index << PAGE_SHIFT; int ret; int i; int i_done; @@ -1290,8 +1291,7 @@ static int cluster_pages_for_defrag(struct inode *inode, page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
ret = btrfs_delalloc_reserve_space(BTRFS_I(inode), &data_reserved, - start_index << PAGE_SHIFT, - page_cnt << PAGE_SHIFT); + start, page_cnt << PAGE_SHIFT); if (ret) return ret; i_done = 0; @@ -1380,8 +1380,7 @@ again: btrfs_mod_outstanding_extents(BTRFS_I(inode), 1); spin_unlock(&BTRFS_I(inode)->lock); btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved, - start_index << PAGE_SHIFT, - (page_cnt - i_done) << PAGE_SHIFT, true); + start, (page_cnt - i_done) << PAGE_SHIFT, true); }
@@ -1408,8 +1407,7 @@ out: put_page(pages[i]); } btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved, - start_index << PAGE_SHIFT, - page_cnt << PAGE_SHIFT, true); + start, page_cnt << PAGE_SHIFT, true); btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT); extent_changeset_free(data_reserved); return ret;