From: Su Yue Date: Sun, 3 Jan 2021 09:28:03 +0000 (+0800) Subject: btrfs: prevent NULL pointer dereference in extent_io_tree_panic X-Git-Tag: v5.4.91~74 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=82d1a5f6f2e5cc95b80a0e9cff9ee3654b61fe29;p=thirdparty%2Fkernel%2Fstable.git btrfs: prevent NULL pointer dereference in extent_io_tree_panic commit 29b665cc51e8b602bf2a275734349494776e3dbc upstream. Some extent io trees are initialized with NULL private member (e.g. btrfs_device::alloc_state and btrfs_fs_info::excluded_extents). Dereference of a NULL tree->private as inode pointer will cause panic. Pass tree->fs_info as it's known to be valid in all cases. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=208929 Fixes: 05912a3c04eb ("btrfs: drop extent_io_ops::tree_fs_info callback") CC: stable@vger.kernel.org # 4.19+ Reviewed-by: Anand Jain Signed-off-by: Su Yue Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 60c21cfb19480..95205bde240f7 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -647,9 +647,7 @@ alloc_extent_state_atomic(struct extent_state *prealloc) static void extent_io_tree_panic(struct extent_io_tree *tree, int err) { - struct inode *inode = tree->private_data; - - btrfs_panic(btrfs_sb(inode->i_sb), err, + btrfs_panic(tree->fs_info, err, "locking error: extent tree was modified by another thread while locked"); }