linux/fs/btrfs
Su Yue e79a33270d btrfs: Check name_len with boundary in verify dir_item
Originally, verify_dir_item verifies name_len of dir_item with fixed
values but not item boundary.
If corrupted name_len was not bigger than the fixed value, for example
255, the function will think the dir_item is fine. And then reading
beyond boundary will cause crash.

Example:
	1. Corrupt one dir_item name_len to be 255.
        2. Run 'ls -lar /mnt/test/ > /dev/null'
dmesg:
[   48.451449] BTRFS info (device vdb1): disk space caching is enabled
[   48.451453] BTRFS info (device vdb1): has skinny extents
[   48.489420] general protection fault: 0000 [#1] SMP
[   48.489571] Modules linked in: ext4 jbd2 mbcache btrfs xor raid6_pq
[   48.489716] CPU: 1 PID: 2710 Comm: ls Not tainted 4.10.0-rc1 #5
[   48.489853] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
[   48.490008] task: ffff880035df1bc0 task.stack: ffffc90004800000
[   48.490008] RIP: 0010:read_extent_buffer+0xd2/0x190 [btrfs]
[   48.490008] RSP: 0018:ffffc90004803d98 EFLAGS: 00010202
[   48.490008] RAX: 000000000000001b RBX: 000000000000001b RCX: 0000000000000000
[   48.490008] RDX: ffff880079dbf36c RSI: 0005080000000000 RDI: ffff880079dbf368
[   48.490008] RBP: ffffc90004803dc8 R08: ffff880078e8cc48 R09: ffff880000000000
[   48.490008] R10: 0000160000000000 R11: 0000000000001000 R12: ffff880079dbf288
[   48.490008] R13: ffff880078e8ca88 R14: 0000000000000003 R15: ffffc90004803e20
[   48.490008] FS:  00007fef50c60800(0000) GS:ffff88007d400000(0000) knlGS:0000000000000000
[   48.490008] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   48.490008] CR2: 000055f335ac2ff8 CR3: 000000007356d000 CR4: 00000000001406e0
[   48.490008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   48.490008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   48.490008] Call Trace:
[   48.490008]  btrfs_real_readdir+0x3b7/0x4a0 [btrfs]
[   48.490008]  iterate_dir+0x181/0x1b0
[   48.490008]  SyS_getdents+0xa7/0x150
[   48.490008]  ? fillonedir+0x150/0x150
[   48.490008]  entry_SYSCALL_64_fastpath+0x18/0xad
[   48.490008] RIP: 0033:0x7fef5032546b
[   48.490008] RSP: 002b:00007ffeafcdb830 EFLAGS: 00000206 ORIG_RAX: 000000000000004e
[   48.490008] RAX: ffffffffffffffda RBX: 00007fef5061db38 RCX: 00007fef5032546b
[   48.490008] RDX: 0000000000008000 RSI: 000055f335abaff0 RDI: 0000000000000003
[   48.490008] RBP: 00007fef5061dae0 R08: 00007fef5061db48 R09: 0000000000000000
[   48.490008] R10: 000055f335abafc0 R11: 0000000000000206 R12: 00007fef5061db38
[   48.490008] R13: 0000000000008040 R14: 00007fef5061db38 R15: 000000000000270e
[   48.490008] RIP: read_extent_buffer+0xd2/0x190 [btrfs] RSP: ffffc90004803d98
[   48.499455] ---[ end trace 321920d8e8339505 ]---

Fix it by adding a parameter @slot and check name_len with item boundary
by calling btrfs_is_name_len_valid.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
rev
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
..
tests Btrfs: replace tree->mapping with tree->private_data 2017-06-19 18:25:58 +02:00
acl.c posix_acl: Clear SGID bit when setting file permissions 2016-09-22 10:55:32 +02:00
async-thread.c btrfs: fix crash when tracepoint arguments are freed by wq callbacks 2017-01-09 11:24:50 +01:00
async-thread.h btrfs: limit async_work allocation and worker func duration 2016-12-13 11:01:30 -08:00
backref.c btrfs: use GFP_KERNEL in init_ipath 2017-06-19 18:26:02 +02:00
backref.h
btrfs_inode.h Btrfs: fix reported number of inode blocks 2017-04-26 16:27:26 +01:00
check-integrity.c btrfs: sink gfp parameter to btrfs_io_bio_alloc 2017-06-19 18:26:04 +02:00
check-integrity.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
compression.c btrfs: pass bytes to btrfs_bio_alloc 2017-06-19 18:26:03 +02:00
compression.h btrfs: reduce arguments for decompress_bio ops 2017-06-19 18:26:00 +02:00
ctree.c btrfs: adjust includes after vmalloc removal 2017-06-19 18:26:02 +02:00
ctree.h btrfs: Check name_len with boundary in verify dir_item 2017-06-21 19:16:04 +02:00
dedupe.h btrfs: expand cow_file_range() to support in-band dedup and subpage-blocksize 2016-07-26 13:52:25 +02:00
delayed-inode.c btrfs: convert btrfs_delayed_item.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
delayed-inode.h btrfs: convert btrfs_delayed_item.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
delayed-ref.c btrfs: convert btrfs_delayed_ref_node.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
delayed-ref.h btrfs: convert btrfs_delayed_ref_node.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
dev-replace.c Btrfs: switch to div64_u64 if with a u64 divisor 2017-04-18 14:07:26 +02:00
dev-replace.h btrfs: constify device path passed to relevant helpers 2017-02-28 14:26:07 +01:00
dir-item.c btrfs: Check name_len with boundary in verify dir_item 2017-06-21 19:16:04 +02:00
disk-io.c btrfs: move dev stats accounting out of wait_dev_flush 2017-06-21 19:03:39 +02:00
disk-io.h btrfs: btrfs_wait_tree_block_writeback can be void return 2017-06-19 18:26:01 +02:00
export.c btrfs: Make btrfs_ino take a struct btrfs_inode 2017-02-14 15:50:51 +01:00
export.h
extent_io.c btrfs: sink gfp parameter to btrfs_io_bio_alloc 2017-06-19 18:26:04 +02:00
extent_io.h btrfs: sink gfp parameter to btrfs_io_bio_alloc 2017-06-19 18:26:04 +02:00
extent_map.c btrfs: convert extent_map.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
extent_map.h btrfs: convert extent_map.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
extent-tree.c btrfs: Use btrfs_space_info_used instead of opencoding it 2017-06-19 18:26:04 +02:00
file-item.c Btrfs: change how we iterate bios in endio 2017-06-19 18:25:59 +02:00
file.c Btrfs: fix invalid extent maps due to hole punching 2017-06-21 16:52:45 +02:00
free-space-cache.c btrfs: use clear_page where appropriate 2017-04-18 14:07:26 +02:00
free-space-cache.h btrfs: free-space-cache, clean up unnecessary root arguments 2017-02-17 12:03:56 +01:00
free-space-tree.c Btrfs: use memalloc_nofs and kvzalloc() for free space tree bitmaps 2017-06-19 18:26:01 +02:00
free-space-tree.h
hash.c crypto: Work around deallocated stack frame reference gcc bug on sparc. 2017-06-08 17:36:03 +08:00
hash.h btrfs: advertise which crc32c implementation is being used at module load 2016-06-06 14:08:28 +02:00
inode-item.c btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
inode-map.c btrfs: all btrfs_delalloc_release_metadata take btrfs_inode 2017-02-28 11:30:07 +01:00
inode-map.h
inode.c btrfs: Check name_len with boundary in verify dir_item 2017-06-21 19:16:04 +02:00
ioctl.c btrfs: use GFP_KERNEL in init_ipath 2017-06-19 18:26:02 +02:00
Kconfig
locking.c
locking.h
lzo.c btrfs: switch to kvmalloc and GFP_KERNEL in lzo/zlib alloc_workspace 2017-06-19 18:26:02 +02:00
Makefile
math.h
ordered-data.c btrfs: convert btrfs_ordered_extent.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
ordered-data.h btrfs: convert btrfs_ordered_extent.refs from atomic_t to refcount_t 2017-04-18 14:07:23 +02:00
orphan.c
print-tree.c Btrfs: let btrfs_print_leaf print more about block group 2017-06-19 18:26:00 +02:00
print-tree.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
props.c btrfs: Make btrfs_ino take a struct btrfs_inode 2017-02-14 15:50:51 +01:00
props.h
qgroup.c btrfs: add cond_resched to btrfs_qgroup_trace_leaf_items 2017-06-21 15:48:01 +02:00
qgroup.h btrfs: qgroup: Re-arrange tracepoint timing to co-operate with reserved space tracepoint 2017-04-18 14:07:26 +02:00
raid56.c btrfs: sink gfp parameter to btrfs_io_bio_alloc 2017-06-19 18:26:04 +02:00
raid56.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
rcu-string.h
reada.c btrfs: remove unused member err from reada_extent 2017-06-19 18:25:59 +02:00
relocation.c Btrfs: replace tree->mapping with tree->private_data 2017-06-19 18:25:58 +02:00
root-tree.c btrfs: Use ktime_get_real_ts for root ctime 2017-04-18 14:07:27 +02:00
scrub.c btrfs: sink gfp parameter to btrfs_io_bio_alloc 2017-06-19 18:26:04 +02:00
send.c Btrfs: incremental send, fix invalid path for unlink commands 2017-06-21 16:53:10 +02:00
send.h
struct-funcs.c btrfs: fix string and comment grammatical issues and typos 2016-05-25 22:35:14 +02:00
super.c btrfs: obsolete and remove mount option alloc_start 2017-06-20 14:22:48 +02:00
sysfs.c btrfs: Add quota_override knob into sysfs 2017-06-19 18:25:58 +02:00
sysfs.h
transaction.c btrfs: move fs_info::fs_frozen to the flags 2017-06-20 14:22:42 +02:00
transaction.h btrfs: remove unused qgroup members from btrfs_trans_handle 2017-04-18 14:07:25 +02:00
tree-defrag.c
tree-log.c btrfs: Check name_len with boundary in verify dir_item 2017-06-21 19:16:04 +02:00
tree-log.h btrfs: Make btrfs_del_inode_ref take btrfs_inode 2017-02-14 15:50:54 +01:00
ulist.c btrfs: ulist: rename ulist_fini to ulist_release 2017-02-17 12:03:50 +01:00
ulist.h btrfs: ulist: rename ulist_fini to ulist_release 2017-02-17 12:03:50 +01:00
uuid-tree.c btrfs: return the actual error value from from btrfs_uuid_tree_iterate 2016-12-19 18:08:15 +01:00
volumes.c btrfs: preallocate device flush bio 2017-06-21 19:03:38 +02:00
volumes.h btrfs: preallocate device flush bio 2017-06-21 19:03:38 +02:00
xattr.c btrfs: Check name_len with boundary in verify dir_item 2017-06-21 19:16:04 +02:00
xattr.h btrfs: Switch to generic xattr handlers 2016-05-17 19:17:09 -04:00
zlib.c btrfs: switch to kvmalloc and GFP_KERNEL in lzo/zlib alloc_workspace 2017-06-19 18:26:02 +02:00