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Aurelien Aptel ccd48ec3d4 smb2: fix use-after-free in smb2_ioctl_query_info()
* rqst[1,2,3] is allocated in vars
* each rqst->rq_iov is also allocated in vars or using pooled memory

SMB2_open_free, SMB2_ioctl_free, SMB2_query_info_free are iterating on
each rqst after vars has been freed (use-after-free), and they are
freeing the kvec a second time (double-free).

How to trigger:

* compile with KASAN
* mount a share

$ smbinfo quota /mnt/foo
Segmentation fault
$ dmesg

 ==================================================================
 BUG: KASAN: use-after-free in SMB2_open_free+0x1c/0xa0
 Read of size 8 at addr ffff888007b10c00 by task python3/1200

 CPU: 2 PID: 1200 Comm: python3 Not tainted 5.12.0-rc6+ #107
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
 Call Trace:
  dump_stack+0x93/0xc2
  print_address_description.constprop.0+0x18/0x130
  ? SMB2_open_free+0x1c/0xa0
  ? SMB2_open_free+0x1c/0xa0
  kasan_report.cold+0x7f/0x111
  ? smb2_ioctl_query_info+0x240/0x990
  ? SMB2_open_free+0x1c/0xa0
  SMB2_open_free+0x1c/0xa0
  smb2_ioctl_query_info+0x2bf/0x990
  ? smb2_query_reparse_tag+0x600/0x600
  ? cifs_mapchar+0x250/0x250
  ? rcu_read_lock_sched_held+0x3f/0x70
  ? cifs_strndup_to_utf16+0x12c/0x1c0
  ? rwlock_bug.part.0+0x60/0x60
  ? rcu_read_lock_sched_held+0x3f/0x70
  ? cifs_convert_path_to_utf16+0xf8/0x140
  ? smb2_check_message+0x6f0/0x6f0
  cifs_ioctl+0xf18/0x16b0
  ? smb2_query_reparse_tag+0x600/0x600
  ? cifs_readdir+0x1800/0x1800
  ? selinux_bprm_creds_for_exec+0x4d0/0x4d0
  ? do_user_addr_fault+0x30b/0x950
  ? __x64_sys_openat+0xce/0x140
  __x64_sys_ioctl+0xb9/0xf0
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7fdcf1f4ba87
 Code: b3 66 90 48 8b 05 11 14 2c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 13 2c 00 f7 d8 64 89 01 48
 RSP: 002b:00007ffef1ce7748 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
 RAX: ffffffffffffffda RBX: 00000000c018cf07 RCX: 00007fdcf1f4ba87
 RDX: 0000564c467c5590 RSI: 00000000c018cf07 RDI: 0000000000000003
 RBP: 00007ffef1ce7770 R08: 00007ffef1ce7420 R09: 00007fdcf0e0562b
 R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000004018
 R13: 0000000000000001 R14: 0000000000000003 R15: 0000564c467c5590

 Allocated by task 1200:
  kasan_save_stack+0x1b/0x40
  __kasan_kmalloc+0x7a/0x90
  smb2_ioctl_query_info+0x10e/0x990
  cifs_ioctl+0xf18/0x16b0
  __x64_sys_ioctl+0xb9/0xf0
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae

 Freed by task 1200:
  kasan_save_stack+0x1b/0x40
  kasan_set_track+0x1c/0x30
  kasan_set_free_info+0x20/0x30
  __kasan_slab_free+0xe5/0x110
  slab_free_freelist_hook+0x53/0x130
  kfree+0xcc/0x320
  smb2_ioctl_query_info+0x2ad/0x990
  cifs_ioctl+0xf18/0x16b0
  __x64_sys_ioctl+0xb9/0xf0
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae

 The buggy address belongs to the object at ffff888007b10c00
  which belongs to the cache kmalloc-512 of size 512
 The buggy address is located 0 bytes inside of
  512-byte region [ffff888007b10c00, ffff888007b10e00)
 The buggy address belongs to the page:
 page:0000000044e14b75 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7b10
 head:0000000044e14b75 order:2 compound_mapcount:0 compound_pincount:0
 flags: 0x100000000010200(slab|head)
 raw: 0100000000010200 ffffea000015f500 0000000400000004 ffff888001042c80
 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff888007b10b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff888007b10b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 >ffff888007b10c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                    ^
  ffff888007b10c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff888007b10d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ==================================================================

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-04-25 16:28:24 -05:00
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block block: return -EBUSY when there are open partitions in blkdev_reread_part 2021-04-21 10:49:37 -06:00
certs certs: Replace K{U,G}IDT_INIT() with GLOBAL_ROOT_{U,G}ID 2021-01-21 16:16:10 +00:00
crypto crypto: mips/poly1305 - enable for all MIPS processors 2021-03-08 11:52:17 +01:00
Documentation Documentation/admin-guide/cifs: document open_files and dfscache 2021-04-25 16:28:22 -05:00
drivers Late pin control fixes for v5.12: 2021-04-23 17:11:10 -07:00
fs smb2: fix use-after-free in smb2_ioctl_query_info() 2021-04-25 16:28:24 -05:00
include gpio fixes for v5.12 2021-04-23 10:19:19 -07:00
init Merge branch 'akpm' (patches from Andrew) 2021-03-14 12:23:34 -07:00
ipc fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
kernel - Fix ordering in the queued writer lock's slowpath. 2021-04-25 09:10:10 -07:00
lib lib: remove "expecting prototype" kernel-doc warnings 2021-04-16 16:10:37 -07:00
LICENSES LICENSES: Add the CC-BY-4.0 license 2020-12-08 10:33:27 -07:00
mm mm/filemap: fix mapping_seek_hole_data on THP & 32-bit 2021-04-23 14:42:39 -07:00
net Revert "net/rds: Avoid potential use after free in rds_send_remove_from_sock" 2021-04-24 09:32:35 -07:00
samples Merge git://git.kernel.org:/pub/scm/linux/kernel/git/netdev/net 2021-03-09 17:15:56 -08:00
scripts kasan: remove redundant config option 2021-04-16 16:10:36 -07:00
security KEYS: trusted: Fix TPM reservation for seal/unseal 2021-04-21 16:28:20 -07:00
sound sound fixes for 5.12-rc7 2021-04-08 09:01:30 -07:00
tools perf tools fixes for v5.12: 4th batch 2021-04-25 09:48:46 -07:00
usr Kbuild updates for v5.12 2021-02-25 10:17:31 -08:00
virt KVM: x86/mmu: Consider the hva in mmu_notifier retry 2021-02-22 13:16:53 -05:00
.clang-format cxl for 5.12 2021-02-24 09:38:36 -08:00
.cocciconfig
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.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore clang-lto series for v5.12-rc1 2021-02-23 09:28:51 -08:00
.mailmap .mailmap: fix old email addresses 2021-04-09 14:54:23 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS treewide: Miguel has moved 2021-02-26 09:41:03 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS ARM SoC fixes for v5.12, part 2 2021-04-18 13:23:26 -07:00
Makefile Linux 5.12 2021-04-25 13:49:08 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.