From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Xu Wen <wen.xu@gatech.edu>,
Qu Wenruo <wqu@suse.com>, Gu Jinxiang <gujx@cn.fujitsu.com>,
Nikolay Borisov <nborisov@suse.com>,
David Sterba <dsterba@suse.com>,
Ben Hutchings <ben.hutchings@codethink.co.uk>
Subject: [PATCH 4.9 078/101] btrfs: tree-checker: Verify block_group_item
Date: Thu, 6 Dec 2018 15:39:17 +0100 [thread overview]
Message-ID: <20181206143016.658840881@linuxfoundation.org> (raw)
In-Reply-To: <20181206143011.174892052@linuxfoundation.org>
4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Qu Wenruo <wqu@suse.com>
commit fce466eab7ac6baa9d2dcd88abcf945be3d4a089 upstream.
A crafted image with invalid block group items could make free space cache
code to cause panic.
We could detect such invalid block group item by checking:
1) Item size
Known fixed value.
2) Block group size (key.offset)
We have an upper limit on block group item (10G)
3) Chunk objectid
Known fixed value.
4) Type
Only 4 valid type values, DATA, METADATA, SYSTEM and DATA|METADATA.
No more than 1 bit set for profile type.
5) Used space
No more than the block group size.
This should allow btrfs to detect and refuse to mount the crafted image.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=199849
Reported-by: Xu Wen <wen.xu@gatech.edu>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[bwh: Backported to 4.9:
- In check_leaf_item(), pass root->fs_info to check_block_group_item()
- Adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/btrfs/tree-checker.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++
fs/btrfs/volumes.c | 2
fs/btrfs/volumes.h | 2
3 files changed, 103 insertions(+), 1 deletion(-)
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -31,6 +31,7 @@
#include "disk-io.h"
#include "compression.h"
#include "hash.h"
+#include "volumes.h"
#define CORRUPT(reason, eb, root, slot) \
btrfs_crit(root->fs_info, \
@@ -312,6 +313,102 @@ static int check_dir_item(struct btrfs_r
return 0;
}
+__printf(4, 5)
+__cold
+static void block_group_err(const struct btrfs_fs_info *fs_info,
+ const struct extent_buffer *eb, int slot,
+ const char *fmt, ...)
+{
+ struct btrfs_key key;
+ struct va_format vaf;
+ va_list args;
+
+ btrfs_item_key_to_cpu(eb, &key, slot);
+ va_start(args, fmt);
+
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ btrfs_crit(fs_info,
+ "corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
+ btrfs_header_level(eb) == 0 ? "leaf" : "node",
+ btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
+ key.objectid, key.offset, &vaf);
+ va_end(args);
+}
+
+static int check_block_group_item(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *leaf,
+ struct btrfs_key *key, int slot)
+{
+ struct btrfs_block_group_item bgi;
+ u32 item_size = btrfs_item_size_nr(leaf, slot);
+ u64 flags;
+ u64 type;
+
+ /*
+ * Here we don't really care about alignment since extent allocator can
+ * handle it. We care more about the size, as if one block group is
+ * larger than maximum size, it's must be some obvious corruption.
+ */
+ if (key->offset > BTRFS_MAX_DATA_CHUNK_SIZE || key->offset == 0) {
+ block_group_err(fs_info, leaf, slot,
+ "invalid block group size, have %llu expect (0, %llu]",
+ key->offset, BTRFS_MAX_DATA_CHUNK_SIZE);
+ return -EUCLEAN;
+ }
+
+ if (item_size != sizeof(bgi)) {
+ block_group_err(fs_info, leaf, slot,
+ "invalid item size, have %u expect %zu",
+ item_size, sizeof(bgi));
+ return -EUCLEAN;
+ }
+
+ read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
+ sizeof(bgi));
+ if (btrfs_block_group_chunk_objectid(&bgi) !=
+ BTRFS_FIRST_CHUNK_TREE_OBJECTID) {
+ block_group_err(fs_info, leaf, slot,
+ "invalid block group chunk objectid, have %llu expect %llu",
+ btrfs_block_group_chunk_objectid(&bgi),
+ BTRFS_FIRST_CHUNK_TREE_OBJECTID);
+ return -EUCLEAN;
+ }
+
+ if (btrfs_block_group_used(&bgi) > key->offset) {
+ block_group_err(fs_info, leaf, slot,
+ "invalid block group used, have %llu expect [0, %llu)",
+ btrfs_block_group_used(&bgi), key->offset);
+ return -EUCLEAN;
+ }
+
+ flags = btrfs_block_group_flags(&bgi);
+ if (hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1) {
+ block_group_err(fs_info, leaf, slot,
+"invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
+ flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
+ hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
+ return -EUCLEAN;
+ }
+
+ type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
+ if (type != BTRFS_BLOCK_GROUP_DATA &&
+ type != BTRFS_BLOCK_GROUP_METADATA &&
+ type != BTRFS_BLOCK_GROUP_SYSTEM &&
+ type != (BTRFS_BLOCK_GROUP_METADATA |
+ BTRFS_BLOCK_GROUP_DATA)) {
+ block_group_err(fs_info, leaf, slot,
+"invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llu or 0x%llx",
+ type, hweight64(type),
+ BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
+ BTRFS_BLOCK_GROUP_SYSTEM,
+ BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
+ return -EUCLEAN;
+ }
+ return 0;
+}
+
/*
* Common point to switch the item-specific validation.
*/
@@ -333,6 +430,9 @@ static int check_leaf_item(struct btrfs_
case BTRFS_XATTR_ITEM_KEY:
ret = check_dir_item(root, leaf, key, slot);
break;
+ case BTRFS_BLOCK_GROUP_ITEM_KEY:
+ ret = check_block_group_item(root->fs_info, leaf, key, slot);
+ break;
}
return ret;
}
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -4656,7 +4656,7 @@ static int __btrfs_alloc_chunk(struct bt
if (type & BTRFS_BLOCK_GROUP_DATA) {
max_stripe_size = SZ_1G;
- max_chunk_size = 10 * max_stripe_size;
+ max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE;
if (!devs_max)
devs_max = BTRFS_MAX_DEVS(info->chunk_root);
} else if (type & BTRFS_BLOCK_GROUP_METADATA) {
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -24,6 +24,8 @@
#include <linux/btrfs.h>
#include "async-thread.h"
+#define BTRFS_MAX_DATA_CHUNK_SIZE (10ULL * SZ_1G)
+
extern struct mutex uuid_mutex;
#define BTRFS_STRIPE_LEN SZ_64K
next prev parent reply other threads:[~2018-12-06 14:48 UTC|newest]
Thread overview: 115+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-06 14:37 [PATCH 4.9 000/101] 4.9.144-stable review Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 001/101] Kbuild: suppress packed-not-aligned warning for default setting only Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 002/101] disable stringop truncation warnings for now Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 003/101] test_hexdump: use memcpy instead of strncpy Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 004/101] kobject: Replace strncpy with memcpy Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 005/101] unifdef: use memcpy instead of strncpy Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 006/101] kernfs: Replace strncpy with memcpy Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 007/101] ip_tunnel: Fix name string concatenate in __ip_tunnel_create() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 008/101] drm: gma500: fix logic error Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 009/101] scsi: bfa: convert to strlcpy/strlcat Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 010/101] staging: rts5208: fix gcc-8 logic error warning Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 011/101] kdb: use memmove instead of overlapping memcpy Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 012/101] x86/power/64: Use char arrays for asm function names Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 013/101] iser: set sector for ambiguous mr status errors Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 014/101] uprobes: Fix handle_swbp() vs. unregister() + register() race once more Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 015/101] MIPS: ralink: Fix mt7620 nd_sd pinmux Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 016/101] mips: fix mips_get_syscall_arg o32 check Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 017/101] IB/mlx5: Avoid load failure due to unknown link width Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 018/101] drm/ast: Fix incorrect free on ioregs Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 019/101] drm: set is_master to 0 upon drm_new_set_master() failure Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 020/101] scsi: scsi_devinfo: cleanly zero-pad devinfo strings Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 021/101] ALSA: trident: Suppress gcc string warning Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 022/101] scsi: csiostor: Avoid content leaks and casts Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 023/101] kgdboc: Fix restrict error Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 024/101] kgdboc: Fix warning with module build Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 025/101] binder: fix proc->files use-after-free Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 026/101] svm: Add mutex_lock to protect apic_access_page_done on AMD systems Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 027/101] drm/mediatek: fix OF sibling-node lookup Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 028/101] Input: xpad - quirk all PDP Xbox One gamepads Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 029/101] Input: matrix_keypad - check for errors from of_get_named_gpio() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 030/101] Input: elan_i2c - add ELAN0620 to the ACPI table Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 031/101] Input: elan_i2c - add ACPI ID for Lenovo IdeaPad 330-15ARR Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 032/101] Input: elan_i2c - add support for ELAN0621 touchpad Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 033/101] btrfs: Always try all copies when reading extent buffers Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 034/101] Btrfs: fix use-after-free when dumping free space Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 035/101] ARC: change defconfig defaults to ARCv2 Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 036/101] arc: [devboards] Add support of NFSv3 ACL Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 037/101] udf: Allow mounting volumes with incorrect identification strings Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 038/101] reset: make optional functions really optional Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 039/101] reset: core: fix reset_control_put Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 040/101] reset: fix optional reset_control_get stubs to return NULL Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 041/101] reset: add exported __reset_control_get, return NULL if optional Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 042/101] reset: make device_reset_optional() really optional Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 043/101] reset: remove remaining WARN_ON() in <linux/reset.h> Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 044/101] mm: cleancache: fix corruption on missed inode invalidation Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 045/101] usb: gadget: dummy: fix nonsensical comparisons Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 046/101] net: qed: use correct strncpy() size Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 047/101] tipc: use destination length for copy string Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 048/101] libceph: drop len argument of *verify_authorizer_reply() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 049/101] libceph: no need to drop con->mutex for ->get_authorizer() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 050/101] libceph: store ceph_auth_handshake pointer in ceph_connection Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 051/101] libceph: factor out __prepare_write_connect() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 052/101] libceph: factor out __ceph_x_decrypt() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 053/101] libceph: factor out encrypt_authorizer() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 054/101] libceph: add authorizer challenge Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 055/101] libceph: implement CEPHX_V2 calculation mode Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 056/101] libceph: weaken sizeof check in ceph_x_verify_authorizer_reply() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 057/101] libceph: check authorizer reply/challenge length before reading Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 058/101] bpf/verifier: Add spi variable to check_stack_write() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 059/101] bpf/verifier: Pass instruction index to check_mem_access() and check_xadd() Greg Kroah-Hartman
2018-12-06 14:38 ` [PATCH 4.9 060/101] bpf: Prevent memory disambiguation attack Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 061/101] wil6210: missing length check in wmi_set_ie Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 062/101] mm/hugetlb.c: dont call region_abort if region_chg fails Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 063/101] hugetlbfs: fix offset overflow in hugetlbfs mmap Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 064/101] hugetlbfs: check for pgoff value overflow Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 065/101] btrfs: validate type when reading a chunk Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 066/101] btrfs: Verify that every chunk has corresponding block group at mount time Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 067/101] btrfs: Refactor check_leaf function for later expansion Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 068/101] btrfs: Check if item pointer overlaps with the item itself Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 069/101] btrfs: Add sanity check for EXTENT_DATA when reading out leaf Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 070/101] btrfs: Add checker for EXTENT_CSUM Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 071/101] btrfs: Move leaf and node validation checker to tree-checker.c Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 072/101] btrfs: struct-funcs, constify readers Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 073/101] btrfs: tree-checker: Enhance btrfs_check_node output Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 074/101] btrfs: tree-checker: Fix false panic for sanity test Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 075/101] btrfs: tree-checker: Add checker for dir item Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 076/101] btrfs: tree-checker: use %zu format string for size_t Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 077/101] btrfs: tree-check: reduce stack consumption in check_dir_item Greg Kroah-Hartman
2018-12-06 14:39 ` Greg Kroah-Hartman [this message]
2018-12-06 14:39 ` [PATCH 4.9 079/101] btrfs: tree-checker: Detect invalid and empty essential trees Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 080/101] btrfs: Check that each block group has corresponding chunk at mount time Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 081/101] btrfs: tree-checker: Check level for leaves and nodes Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 082/101] btrfs: tree-checker: Fix misleading group system information Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 083/101] f2fs: fix a panic caused by NULL flush_cmd_control Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 084/101] f2fs: fix race condition in between free nid allocator/initializer Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 085/101] f2fs: detect wrong layout Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 086/101] f2fs: return error during fill_super Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 087/101] f2fs: check blkaddr more accuratly before issue a bio Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 088/101] f2fs: sanity check on sit entry Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 089/101] f2fs: enhance sanity_check_raw_super() to avoid potential overflow Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 090/101] f2fs: clean up with is_valid_blkaddr() Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 091/101] f2fs: introduce and spread verify_blkaddr Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 092/101] f2fs: fix to do sanity check with secs_per_zone Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 093/101] f2fs: fix to do sanity check with user_block_count Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 094/101] f2fs: Add sanity_check_inode() function Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 095/101] f2fs: fix to do sanity check with node footer and iblocks Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 096/101] f2fs: fix to do sanity check with block address in main area Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 097/101] f2fs: fix missing up_read Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 098/101] f2fs: fix to do sanity check with block address in main area v2 Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 099/101] f2fs: free meta pages if sanity check for ckpt is failed Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 100/101] f2fs: fix to do sanity check with cp_pack_start_sum Greg Kroah-Hartman
2018-12-07 18:12 ` Ben Hutchings
2018-12-08 9:01 ` Greg Kroah-Hartman
2018-12-06 14:39 ` [PATCH 4.9 101/101] xfs: dont fail when converting shortform attr to long form during ATTR_REPLACE Greg Kroah-Hartman
2018-12-06 20:12 ` [PATCH 4.9 000/101] 4.9.144-stable review kernelci.org bot
2018-12-06 22:08 ` shuah
2018-12-07 9:03 ` Jon Hunter
2018-12-07 14:41 ` Greg Kroah-Hartman
2018-12-07 9:10 ` Naresh Kamboju
2018-12-07 14:41 ` Greg Kroah-Hartman
2018-12-07 15:34 ` Ben Hutchings
2018-12-07 15:51 ` Greg Kroah-Hartman
2018-12-07 17:53 ` Naresh Kamboju
2018-12-08 8:39 ` Greg Kroah-Hartman
2018-12-07 23:38 ` Guenter Roeck
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