From: Greg Kroah-Hartman Date: Mon, 21 May 2018 06:50:54 +0000 (+0200) Subject: drop btrfs patch from 3.18 X-Git-Tag: v4.9.102~15 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=927403fcda1be913d3b43b94a107ade079041efb;p=thirdparty%2Fkernel%2Fstable-queue.git drop btrfs patch from 3.18 --- diff --git a/queue-3.18/btrfs-send-fix-invalid-access-to-commit-roots-due-to-concurrent-snapshotting.patch b/queue-3.18/btrfs-send-fix-invalid-access-to-commit-roots-due-to-concurrent-snapshotting.patch deleted file mode 100644 index 8c320dab031..00000000000 --- a/queue-3.18/btrfs-send-fix-invalid-access-to-commit-roots-due-to-concurrent-snapshotting.patch +++ /dev/null @@ -1,136 +0,0 @@ -From 6f2f0b394b54e2b159ef969a0b5274e9bbf82ff2 Mon Sep 17 00:00:00 2001 -From: Robbie Ko -Date: Mon, 14 May 2018 10:51:34 +0800 -Subject: Btrfs: send, fix invalid access to commit roots due to concurrent snapshotting - -From: Robbie Ko - -commit 6f2f0b394b54e2b159ef969a0b5274e9bbf82ff2 upstream. - -[BUG] -btrfs incremental send BUG happens when creating a snapshot of snapshot -that is being used by send. - -[REASON] -The problem can happen if while we are doing a send one of the snapshots -used (parent or send) is snapshotted, because snapshoting implies COWing -the root of the source subvolume/snapshot. - -1. When doing an incremental send, the send process will get the commit - roots from the parent and send snapshots, and add references to them - through extent_buffer_get(). - -2. When a snapshot/subvolume is snapshotted, its root node is COWed - (transaction.c:create_pending_snapshot()). - -3. COWing releases the space used by the node immediately, through: - - __btrfs_cow_block() - --btrfs_free_tree_block() - ----btrfs_add_free_space(bytenr of node) - -4. Because send doesn't hold a transaction open, it's possible that - the transaction used to create the snapshot commits, switches the - commit root and the old space used by the previous root node gets - assigned to some other node allocation. Allocation of a new node will - use the existing extent buffer found in memory, which we previously - got a reference through extent_buffer_get(), and allow the extent - buffer's content (pages) to be modified: - - btrfs_alloc_tree_block - --btrfs_reserve_extent - ----find_free_extent (get bytenr of old node) - --btrfs_init_new_buffer (use bytenr of old node) - ----btrfs_find_create_tree_block - ------alloc_extent_buffer - --------find_extent_buffer (get old node) - -5. So send can access invalid memory content and have unpredictable - behaviour. - -[FIX] -So we fix the problem by copying the commit roots of the send and -parent snapshots and use those copies. - -CallTrace looks like this: - ------------[ cut here ]------------ - kernel BUG at fs/btrfs/ctree.c:1861! - invalid opcode: 0000 [#1] SMP - CPU: 6 PID: 24235 Comm: btrfs Tainted: P O 3.10.105 #23721 - ffff88046652d680 ti: ffff88041b720000 task.ti: ffff88041b720000 - RIP: 0010:[] read_node_slot+0x108/0x110 [btrfs] - RSP: 0018:ffff88041b723b68 EFLAGS: 00010246 - RAX: ffff88043ca6b000 RBX: ffff88041b723c50 RCX: ffff880000000000 - RDX: 000000000000004c RSI: ffff880314b133f8 RDI: ffff880458b24000 - RBP: 0000000000000000 R08: 0000000000000001 R09: ffff88041b723c66 - R10: 0000000000000001 R11: 0000000000001000 R12: ffff8803f3e48890 - R13: ffff8803f3e48880 R14: ffff880466351800 R15: 0000000000000001 - FS: 00007f8c321dc8c0(0000) GS:ffff88047fcc0000(0000) - CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 - R2: 00007efd1006d000 CR3: 0000000213a24000 CR4: 00000000003407e0 - DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 - DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 - Stack: - ffff88041b723c50 ffff8803f3e48880 ffff8803f3e48890 ffff8803f3e48880 - ffff880466351800 0000000000000001 ffffffffa08dd9d7 ffff88041b723c50 - ffff8803f3e48880 ffff88041b723c66 ffffffffa08dde85 a9ff88042d2c4400 - Call Trace: - [] ? tree_move_down.isra.33+0x27/0x50 [btrfs] - [] ? tree_advance+0xb5/0xc0 [btrfs] - [] ? btrfs_compare_trees+0x2d4/0x760 [btrfs] - [] ? finish_inode_if_needed+0x870/0x870 [btrfs] - [] ? btrfs_ioctl_send+0xeda/0x1050 [btrfs] - [] ? btrfs_ioctl+0x1e3d/0x33f0 [btrfs] - [] ? handle_pte_fault+0x373/0x990 - [] ? atomic_notifier_call_chain+0x16/0x20 - [] ? set_task_cpu+0xb6/0x1d0 - [] ? handle_mm_fault+0x143/0x2a0 - [] ? __do_page_fault+0x1d0/0x500 - [] ? check_preempt_curr+0x57/0x90 - [] ? do_vfs_ioctl+0x4aa/0x990 - [] ? do_fork+0x113/0x3b0 - [] ? trace_hardirqs_off_thunk+0x3a/0x6c - [] ? SyS_ioctl+0x88/0xa0 - [] ? system_call_fastpath+0x16/0x1b - ---[ end trace 29576629ee80b2e1 ]--- - -Fixes: 7069830a9e38 ("Btrfs: add btrfs_compare_trees function") -CC: stable@vger.kernel.org # 3.6+ -Signed-off-by: Robbie Ko -Reviewed-by: Filipe Manana -Signed-off-by: David Sterba -Signed-off-by: Greg Kroah-Hartman - ---- - fs/btrfs/ctree.c | 16 ++++++++++++++-- - 1 file changed, 14 insertions(+), 2 deletions(-) - ---- a/fs/btrfs/ctree.c -+++ b/fs/btrfs/ctree.c -@@ -5399,12 +5399,24 @@ int btrfs_compare_trees(struct btrfs_roo - down_read(&left_root->fs_info->commit_root_sem); - left_level = btrfs_header_level(left_root->commit_root); - left_root_level = left_level; -- left_path->nodes[left_level] = left_root->commit_root; -+ left_path->nodes[left_level] = -+ btrfs_clone_extent_buffer(left_root->commit_root); -+ if (!left_path->nodes[left_level]) { -+ up_read(&fs_info->commit_root_sem); -+ ret = -ENOMEM; -+ goto out; -+ } - extent_buffer_get(left_path->nodes[left_level]); - - right_level = btrfs_header_level(right_root->commit_root); - right_root_level = right_level; -- right_path->nodes[right_level] = right_root->commit_root; -+ right_path->nodes[right_level] = -+ btrfs_clone_extent_buffer(right_root->commit_root); -+ if (!right_path->nodes[right_level]) { -+ up_read(&fs_info->commit_root_sem); -+ ret = -ENOMEM; -+ goto out; -+ } - extent_buffer_get(right_path->nodes[right_level]); - up_read(&left_root->fs_info->commit_root_sem); - diff --git a/queue-3.18/series b/queue-3.18/series index 8edf511eebf..8e993f3b6cb 100644 --- a/queue-3.18/series +++ b/queue-3.18/series @@ -39,4 +39,3 @@ efi-avoid-potential-crashes-fix-the-struct-efi_pci_io_protocol_32-definition-for arm-8771-1-kprobes-prohibit-kprobes-on-do_undefinstr.patch tick-broadcast-use-for_each_cpu-specially-on-up-kernels.patch arm-8772-1-kprobes-prohibit-kprobes-on-get_user-functions.patch -btrfs-send-fix-invalid-access-to-commit-roots-due-to-concurrent-snapshotting.patch