linux-brain/fs
Willy Tarreau adc143b97d proc: do not access cmdline nor environ from file-backed areas
commit 7f7ccc2ccc upstream.

proc_pid_cmdline_read() and environ_read() directly access the target
process' VM to retrieve the command line and environment. If this
process remaps these areas onto a file via mmap(), the requesting
process may experience various issues such as extra delays if the
underlying device is slow to respond.

Let's simply refuse to access file-backed areas in these functions.
For this we add a new FOLL_ANON gup flag that is passed to all calls
to access_remote_vm(). The code already takes care of such failures
(including unmapped areas). Accesses via /proc/pid/mem were not
changed though.

This was assigned CVE-2018-1120.

Note for stable backports: the patch may apply to kernels prior to 4.11
but silently miss one location; it must be checked that no call to
access_remote_vm() keeps zero as the last argument.

Reported-by: Qualys Security Advisory <qsa@qualys.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.4:
 - Update the extra call to access_remote_vm() from proc_pid_cmdline_read()
 - Adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17 21:55:17 +01:00
..
9p v9fs_dir_readdir: fix double-free on p9stat_read error 2018-12-01 09:46:33 +01:00
adfs fs/adfs: remove unneeded cast 2015-06-30 19:44:57 -07:00
affs affs_lookup(): close a race with affs_remove_link() 2018-05-30 07:48:51 +02:00
afs afs: Fix afs_kill_pages() 2017-12-20 10:04:56 +01:00
autofs4 autofs: fix autofs_sbi() does not check super block type 2018-09-19 22:49:00 +02:00
befs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-07-04 19:36:06 -07:00
bfs bfs: add sanity check at bfs_fill_super() 2018-12-01 09:46:33 +01:00
btrfs Btrfs: send, fix infinite loop due to directory rename dependencies 2018-12-17 21:55:10 +01:00
cachefiles fscache, cachefiles: remove redundant variable 'cache' 2018-12-17 21:55:12 +01:00
ceph ceph: drop negative child dentries before try pruning inode's alias 2017-12-20 10:04:52 +01:00
cifs cifs: Fix separator when building path from dentry 2018-12-13 09:21:36 +01:00
coda coda: fix 'kernel memory exposure attempt' in fsync 2017-11-24 08:32:25 +01:00
configfs configfs: replace strncpy with memcpy 2018-11-21 09:27:44 +01:00
cramfs Cramfs: fix abad comparison when wrap-arounds occur 2018-11-21 09:27:37 +01:00
debugfs dentry name snapshots 2017-08-06 19:19:42 -07:00
devpts devpts: clean up interface to pty drivers 2016-08-16 09:30:49 +02:00
dlm dlm: avoid double-free on error path in dlm_device_{register,unregister} 2017-09-13 14:09:45 -07:00
ecryptfs do d_instantiate/unlock_new_inode combinations safely 2018-05-30 07:48:52 +02:00
efivarfs efi: Make efivarfs entries immutable by default 2016-03-03 15:07:09 -08:00
efs fs/efs: femove unneeded cast 2015-06-25 17:00:42 -07:00
exofs fs/exofs: fix potential memory leak in mount option parsing 2018-11-27 16:08:00 +01:00
exportfs exportfs: do not read dentry after free 2018-12-17 21:55:10 +01:00
ext2 ext2: fix potential use after free 2018-12-13 09:21:27 +01:00
ext4 ext4: fix buffer leak in __ext4_read_dirblock() on error path 2018-11-21 09:27:44 +01:00
f2fs f2fs: fix to do sanity check with {sit,nat}_ver_bitmap_bytesize 2018-09-19 22:48:59 +02:00
fat fs/fat/fatent.c: add cond_resched() to fat_count_free_clusters() 2018-11-10 07:41:40 -08:00
freevxfs freevxfs: Grammar s/an negative/a negative/ 2015-08-07 13:59:24 +02:00
fscache fscache: fix race between enablement and dropping of object 2018-12-17 21:55:11 +01:00
fuse fuse: fix leaked notify reply 2018-11-21 09:27:44 +01:00
gfs2 gfs2: Don't leave s_fs_info pointing to freed memory in init_sbd 2018-12-01 09:46:33 +01:00
hfs hfs: do not free node before using 2018-12-17 21:55:12 +01:00
hfsplus hfsplus: do not free node before using 2018-12-17 21:55:12 +01:00
hostfs hostfs: Freeing an ERR_PTR in hostfs_fill_sb_common() 2016-09-30 10:18:39 +02:00
hpfs hpfs: implement the show_options method 2016-06-01 12:15:54 -07:00
hugetlbfs hugetlbfs: fix bug in pgoff overflow checking 2018-12-17 21:55:15 +01:00
isofs isofs: fix timestamps beyond 2027 2017-11-30 08:37:20 +00:00
jbd2 jbd2: fix use after free in jbd2_log_do_checkpoint() 2018-11-21 09:27:34 +01:00
jffs2 jffs2: free jffs2_sb_info through jffs2_kill_sb() 2018-11-21 09:27:30 +01:00
jfs jfs: Fix inconsistency between memory allocation and ea_buf->max_size 2018-08-09 12:19:28 +02:00
kernfs kernfs: Replace strncpy with memcpy 2018-12-13 09:21:29 +01:00
lockd lockd: fix access beyond unterminated strings in prints 2018-11-21 09:27:36 +01:00
logfs mm, fs: introduce mapping_gfp_constraint() 2015-11-06 17:50:42 -08:00
minix Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-07-04 19:36:06 -07:00
ncpfs staging: ncpfs: memory corruption in ncp_read_kernel() 2018-03-28 18:40:15 +02:00
nfs NFSv4.1: Fix the r/wsize checking 2018-11-21 09:27:35 +01:00
nfs_common lockd: fix "list_add double add" caused by legacy signal interface 2018-02-03 17:04:28 +01:00
nfsd nfsd: fix corrupted reply to badly ordered compound 2018-10-10 08:52:07 +02:00
nilfs2 do d_instantiate/unlock_new_inode combinations safely 2018-05-30 07:48:52 +02:00
nls
notify fanotify: fix logic of events on child 2018-04-24 09:32:11 +02:00
ntfs mm, fs: introduce mapping_gfp_constraint() 2015-11-06 17:50:42 -08:00
ocfs2 ocfs2: fix potential use after free 2018-12-17 21:55:12 +01:00
omfs omfs: fix potential integer overflow in allocator 2015-05-28 18:25:19 -07:00
openpromfs
overlayfs ovl: proper cleanup of workdir 2018-09-15 09:40:41 +02:00
proc proc: do not access cmdline nor environ from file-backed areas 2018-12-17 21:55:17 +01:00
pstore pstore: Convert console write to use ->write_buf 2018-12-17 21:55:12 +01:00
qnx4
qnx6 pagemap.h: move dir_pages() over there 2015-06-23 18:02:00 -04:00
quota fs/quota: Fix spectre gadget in do_quotactl 2018-09-09 20:04:36 +02:00
ramfs mm, fs: obey gfp_mapping for add_to_page_cache() 2015-10-16 11:42:28 -07:00
reiserfs reiserfs: propagate errors from fill_with_dentries() properly 2018-11-27 16:08:00 +01:00
romfs romfs: use different way to generate fsid for BLOCK or MTD 2017-06-17 06:39:38 +02:00
squashfs squashfs: more metadata hardenings 2018-08-06 16:24:42 +02:00
sysfs scsi: sysfs: Introduce sysfs_{un,}break_active_protection() 2018-09-05 09:18:40 +02:00
sysv sysv: return 'err' instead of 0 in __sysv_write_inode 2018-12-17 21:55:09 +01:00
tracefs tracefs: Fix refcount imbalance in start_creating() 2015-11-04 22:13:45 -05:00
ubifs ubifs: Check for name being NULL while mounting 2018-10-13 09:11:34 +02:00
udf udf: Detect incorrect directory size 2018-07-03 11:21:34 +02:00
ufs do d_instantiate/unlock_new_inode combinations safely 2018-05-30 07:48:52 +02:00
xfs xfs: fix incorrect log_flushed on fsync 2018-06-13 16:15:27 +02:00
Kconfig dax: disable pmd mappings 2015-11-16 23:54:45 -08:00
Kconfig.binfmt
Makefile ext4: promote ext4 over ext2 in the default probe order 2015-10-15 10:33:21 -04:00
aio.c fix io_destroy()/aio_complete() race 2018-06-06 16:46:23 +02:00
anon_inodes.c
attr.c vfs: move permission checking into notify_change() for utimes(NULL) 2016-10-22 12:26:56 +02:00
bad_inode.c
binfmt_aout.c
binfmt_elf.c fs, elf: make sure to page align bss in load_elf_library 2018-11-21 09:27:41 +01:00
binfmt_elf_fdpic.c libnvdimm for 4.4: 2015-11-10 12:07:22 -08:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c fs/binfmt_misc.c: do not allow offset overflow 2018-07-03 11:21:26 +02:00
binfmt_script.c
block_dev.c fs/block_dev: always invalidate cleancache in invalidate_bdev() 2017-05-20 14:27:01 +02:00
buffer.c fs: add i_blocksize() 2017-06-14 13:16:24 +02:00
char_dev.c fs/char_dev.c: fix incorrect documentation for unregister_chrdev_region 2015-08-05 13:49:35 -07:00
compat.c
compat_binfmt_elf.c binfmt_elf: compat: avoid unused function warning 2018-02-25 11:03:51 +01:00
compat_ioctl.c fs: compat: Remove warning from COMPATIBLE_IOCTL 2018-04-08 11:51:57 +02:00
coredump.c coredump: Ensure proper size of sparse core files 2017-07-05 14:37:20 +02:00
dax.c dax: disable pmd mappings 2015-11-16 23:54:45 -08:00
dcache.c fs/dcache.c: fix kmemcheck splat at take_dentry_name_snapshot() 2018-09-15 09:40:38 +02:00
dcookies.c
direct-io.c direct-io: Prevent NULL pointer access in submit_page_section 2017-10-18 09:20:42 +02:00
drop_caches.c inode: convert inode_sb_list_lock to per-sb 2015-08-17 18:39:46 -04:00
eventfd.c
eventpoll.c epoll: fix race between ep_poll_callback(POLLFREE) and ep_free()/ep_remove() 2017-09-07 08:34:10 +02:00
exec.c mm: replace get_user_pages() write/force parameters with gup_flags 2018-12-17 21:55:16 +01:00
fcntl.c fs/fcntl: f_setown, avoid undefined behaviour 2018-01-31 12:06:11 +01:00
fhandle.c fs/coredump: prevent fsuid=0 dumps into user-controlled directories 2016-04-12 09:08:58 -07:00
file.c vfs: clear remainder of 'full_fds_bits' in dup_fd() 2015-11-05 23:05:32 -08:00
file_table.c fs, file table: reinit files_stat.max_files after deferred memory initialisation 2015-08-07 04:39:40 +03:00
filesystems.c
fs-writeback.c bdi: Fix oops in wb_workfn() 2018-05-16 10:06:51 +02:00
fs_pin.c
fs_struct.c
inode.c Fix up non-directory creation in SGID directories 2018-07-17 11:31:43 +02:00
internal.h inode: rename i_wb_list to i_io_list 2015-08-17 23:38:10 -04:00
ioctl.c
libfs.c fs: Set the size of empty dirs to 0. 2015-08-12 15:28:45 -05:00
locks.c locks: don't check for race with close when setting OFD lock 2018-01-17 09:35:27 +01:00
mbcache.c
mount.h mnt: In propgate_umount handle visiting mounts in any order 2017-07-21 07:44:57 +02:00
mpage.c fs: add i_blocksize() 2017-06-14 13:16:24 +02:00
namei.c namei: allow restricted O_CREAT of FIFOs and regular files 2018-12-01 09:46:41 +01:00
namespace.c mount: Prevent MNT_DETACH from disconnecting locked mounts 2018-11-21 09:27:44 +01:00
no-block.c
nsfs.c nsfs: mark dentry with DCACHE_RCUACCESS 2018-02-16 20:09:43 +01:00
open.c fs: completely ignore unknown open flags 2017-07-15 11:57:44 +02:00
pipe.c pipe: cap initial pipe capacity according to pipe-max-size limit 2018-05-26 08:48:51 +02:00
pnode.c mnt: Make propagate_umount less slow for overlapping mount propagation trees 2017-07-21 07:44:58 +02:00
pnode.h mnt: Add a per mount namespace limit on the number of mounts 2017-04-30 05:49:28 +02:00
posix_acl.c tmpfs: clear S_ISGID when setting posix ACLs 2017-01-26 08:23:47 +01:00
proc_namespace.c vfs: show_vfsstat: do not ignore errors from show_devname method 2016-04-12 09:08:55 -07:00
read_write.c vfs: Return -ENXIO for negative SEEK_HOLE / SEEK_DATA offsets 2017-10-05 09:41:45 +02:00
readdir.c
select.c fs/select: add vmalloc fallback for select(2) 2018-01-31 12:06:09 +01:00
seq_file.c Make file credentials available to the seqfile interfaces 2017-08-06 19:19:42 -07:00
signalfd.c signalfd: fix information leak in signalfd_copyinfo 2015-08-07 04:39:40 +03:00
splice.c vfs: fix uninitialized flags in splice_to_pipe() 2017-02-23 17:43:09 +01:00
stack.c
stat.c ufs: restore maintaining ->i_blocks 2017-06-14 13:16:24 +02:00
statfs.c
super.c sget(): handle failures of register_shrinker() 2018-03-03 10:19:41 +01:00
sync.c fs/sync.c: make sync_file_range(2) use WB_SYNC_NONE writeback 2015-11-06 17:50:42 -08:00
timerfd.c timerfd: Protect the might cancel mechanism proper 2017-05-08 07:46:01 +02:00
userfaultfd.c userfaultfd: shmem: __do_fault requires VM_FAULT_NOPAGE 2017-12-20 10:04:53 +01:00
utimes.c vfs: move permission checking into notify_change() for utimes(NULL) 2016-10-22 12:26:56 +02:00
xattr.c getxattr: use correct xattr length 2018-09-09 20:04:36 +02:00