linux/fs
Chris Kennelly ce81bb256a fs/binfmt_elf: use PT_LOAD p_align values for suitable start address
Patch series "Selecting Load Addresses According to p_align", v3.

The current ELF loading mechancism provides page-aligned mappings.  This
can lead to the program being loaded in a way unsuitable for file-backed,
transparent huge pages when handling PIE executables.

While specifying -z,max-page-size=0x200000 to the linker will generate
suitably aligned segments for huge pages on x86_64, the executable needs
to be loaded at a suitably aligned address as well.  This alignment
requires the binary's cooperation, as distinct segments need to be
appropriately paddded to be eligible for THP.

For binaries built with increased alignment, this limits the number of
bits usable for ASLR, but provides some randomization over using fixed
load addresses/non-PIE binaries.

This patch (of 2):

The current ELF loading mechancism provides page-aligned mappings.  This
can lead to the program being loaded in a way unsuitable for file-backed,
transparent huge pages when handling PIE executables.

For binaries built with increased alignment, this limits the number of
bits usable for ASLR, but provides some randomization over using fixed
load addresses/non-PIE binaries.

Tested by verifying program with -Wl,-z,max-page-size=0x200000 loading.

[akpm@linux-foundation.org: fix max() warning]
[ckennelly@google.com: augment comment]
  Link: https://lkml.kernel.org/r/20200821233848.3904680-2-ckennelly@google.com

Signed-off-by: Chris Kennelly <ckennelly@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Hugh Dickens <hughd@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: Fangrui Song <maskray@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Link: https://lkml.kernel.org/r/20200820170541.1132271-1-ckennelly@google.com
Link: https://lkml.kernel.org/r/20200820170541.1132271-2-ckennelly@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16 11:11:21 -07:00
..
9p bdi: replace BDI_CAP_NO_{WRITEBACK,ACCT_DIRTY} with a single flag 2020-09-24 13:43:39 -06:00
adfs treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
affs affs: fix basic permission bits to actually work 2020-08-31 12:20:31 +02:00
afs block-5.10-2020-10-12 2020-10-13 12:12:44 -07:00
autofs autofs: use __kernel_write() for the autofs pipe writing 2020-09-29 17:18:34 -07:00
befs block: move struct block_device to blk_types.h 2020-06-24 09:16:02 -06:00
bfs
btrfs block-5.10-2020-10-12 2020-10-13 12:12:44 -07:00
cachefiles cachefiles: switch to kernel_write 2020-07-08 08:27:56 +02:00
ceph We have an inode number handling change, prompted by s390x which is 2020-08-28 10:33:04 -07:00
cifs cifs: Fix incomplete memory allocation on setxattr path 2020-10-10 15:52:54 -07:00
coda
configfs fs: configfs: delete repeated words in comments 2020-10-16 11:11:19 -07:00
cramfs
crypto fscrypt: export fscrypt_d_revalidate() 2020-09-28 14:44:51 -07:00
debugfs debugfs: Fix module state check condition 2020-09-04 18:12:52 +02:00
devpts
dlm dlm for 5.10 2020-10-13 08:59:39 -07:00
ecryptfs mm, treewide: rename kzfree() to kfree_sensitive() 2020-08-07 11:33:22 -07:00
efivarfs efivarfs: Replace invalid slashes with exclamation marks in dentries. 2020-09-25 23:29:04 +02:00
efs block: move struct block_device to blk_types.h 2020-06-24 09:16:02 -06:00
erofs erofs: remove unnecessary enum entries 2020-10-09 10:37:42 +08:00
exfat exfat: fix use of uninitialized spinlock on error path 2020-10-07 14:27:13 +09:00
exportfs
ext2 \n 2020-10-15 14:56:15 -07:00
ext4 mm/readahead: make page_cache_ra_unbounded take a readahead_control 2020-10-16 11:11:16 -07:00
f2fs mm/readahead: make page_cache_ra_unbounded take a readahead_control 2020-10-16 11:11:16 -07:00
fat fat: fix fat_ra_init() for data clusters == 0 2020-08-12 10:58:01 -07:00
freevxfs
fscache Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-06-03 16:27:18 -07:00
fuse block-5.10-2020-10-12 2020-10-13 12:12:44 -07:00
gfs2 Fix memory leak on filesystem withdraw 2020-08-28 10:41:00 -07:00
hfs block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
hfsplus treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
hostfs
hpfs hpfs: fix warning due to superfluous semicolon 2020-06-06 10:08:17 -07:00
hugetlbfs hugetlbfs: prevent filesystem stacking of hugetlbfs 2020-08-12 10:57:56 -07:00
iomap iomap: Call inode_dio_end() before generic_write_sync() 2020-09-28 08:51:08 -07:00
isofs Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
jbd2 jbd2: clean up checksum verification in do_one_pass() 2020-08-19 12:04:35 -04:00
jffs2 treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
jfs fs: Introduce i_blocks_per_page 2020-09-21 08:59:26 -07:00
kernfs fsnotify: pass dir and inode arguments to fsnotify() 2020-07-27 23:15:48 +02:00
lockd
minix fs/minix: remove expected error message in block_to_path() 2020-08-12 10:58:00 -07:00
nfs block-5.10-2020-10-12 2020-10-13 12:12:44 -07:00
nfs_common treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
nfsd block: add a bdev_is_partition helper 2020-09-25 08:18:57 -06:00
nilfs2 treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
nls treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
notify treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
ntfs ntfs: add check for mft record size in superblock 2020-10-13 18:38:27 -07:00
ocfs2 ocfs2: fix potential soft lockup during fstrim 2020-10-13 18:38:27 -07:00
omfs treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
openpromfs
orangefs orangefs: remove unnecessary assignment to variable ret 2020-08-04 15:01:58 -04:00
overlayfs Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
proc mm, oom_adj: don't loop through tasks in __set_oom_adj when not necessary 2020-10-13 18:38:35 -07:00
pstore treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
qnx4
qnx6 fs: convert mpage_readpages to mpage_readahead 2020-06-02 10:59:07 -07:00
quota \n 2020-10-15 14:56:15 -07:00
ramfs
reiserfs reiserfs: Fix oops during mount 2020-10-01 11:15:31 +02:00
romfs romfs: fix uninitialized memory leak in romfs_dev_read() 2020-08-21 09:52:53 -07:00
squashfs squashfs: avoid bio_alloc() failure with 1Mbyte blocks 2020-08-21 09:52:53 -07:00
sysfs sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output 2020-10-02 12:02:30 +02:00
sysv
tracefs
ubifs block-5.10-2020-10-12 2020-10-13 12:12:44 -07:00
udf udf: Limit sparing table size 2020-09-29 17:21:54 +02:00
ufs treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
unicode
vboxsf Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2020-10-15 15:11:56 -07:00
verity fs-verity: use smp_load_acquire() for ->i_verity_info 2020-07-21 16:02:41 -07:00
xfs New code for 5.10: 2020-10-14 14:06:06 -07:00
zonefs zonefs: add zone-capacity support 2020-08-11 17:42:24 +09:00
aio.c Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-12 16:35:51 -07:00
anon_inodes.c
attr.c
bad_inode.c fs: move the fiemap definitions out of fs.h 2020-06-03 23:16:55 -04:00
binfmt_aout.c
binfmt_elf.c fs/binfmt_elf: use PT_LOAD p_align values for suitable start address 2020-10-16 11:11:21 -07:00
binfmt_elf_fdpic.c Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
binfmt_em86.c Merge branch 'akpm' (patches from Andrew) 2020-06-04 19:18:29 -07:00
binfmt_flat.c binfmt_flat: revert "binfmt_flat: don't offset the data start" 2020-08-24 08:49:13 +10:00
binfmt_misc.c Merge branch 'akpm' (patches from Andrew) 2020-06-04 19:18:29 -07:00
binfmt_script.c Merge branch 'akpm' (patches from Andrew) 2020-06-04 19:18:29 -07:00
block_dev.c block: add a bdget_part helper 2020-10-05 10:38:33 -06:00
buffer.c fs: Don't invalidate page buffers in block_write_full_page() 2020-09-07 10:23:07 -06:00
char_dev.c vfs: allow unprivileged whiteout creation 2020-05-14 16:44:23 +02:00
compat_binfmt_elf.c Split the old READ_IMPLIES_EXEC workaround from executable PT_GNU_STACK 2020-06-05 13:45:21 -07:00
coredump.c coredump: add %f for executable filename 2020-08-12 10:58:01 -07:00
d_path.c fs: fix NULL dereference due to data race in prepend_path() 2020-10-14 14:54:45 -07:00
dax.c iomap: Change calling convention for zeroing 2020-09-21 08:59:27 -07:00
dcache.c vfs: Use sequence counter with associated spinlock 2020-07-29 16:14:27 +02:00
dcookies.c
direct-io.c \n 2020-10-15 15:03:10 -07:00
drop_caches.c
eventfd.c
eventpoll.c ep_create_wakeup_source(): dentry name can change under you... 2020-09-24 19:41:58 -04:00
exec.c Char/Misc driver patches for 5.10-rc1 2020-10-15 10:01:51 -07:00
fcntl.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
fhandle.c
file.c io_uring: don't rely on weak ->files references 2020-09-30 20:32:32 -06:00
file_table.c Revert "fs: Do not check if there is a fsnotify watcher on pseudo inodes" 2020-06-29 09:40:55 -07:00
filesystems.c
fs-writeback.c block-5.10-2020-10-12 2020-10-13 12:12:44 -07:00
fs_context.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
fs_parser.c fs_parse: mark fs_param_bad_value() as static 2020-10-13 18:38:27 -07:00
fs_pin.c
fs_struct.c vfs: Use sequence counter with associated spinlock 2020-07-29 16:14:27 +02:00
fs_types.c
fsopen.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
init.c init: add an init_dup helper 2020-08-04 21:02:38 -04:00
inode.c fs: add a filesystem flag for THPs 2020-10-16 11:11:15 -07:00
internal.h fs: remove compat_sys_mount 2020-09-22 23:45:57 -04:00
io-wq.c io-wq: kill unused IO_WORKER_F_EXITING 2020-09-30 20:32:34 -06:00
io-wq.h io_uring: add blkcg accounting to offloaded operations 2020-09-30 20:32:34 -06:00
io_uring.c io_uring-5.10-2020-10-12 2020-10-13 12:36:21 -07:00
ioctl.c fs: remove ksys_ioctl 2020-07-31 08:16:01 +02:00
Kconfig tmpfs: support 64-bit inums per-sb 2020-08-07 11:33:24 -07:00
Kconfig.binfmt treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
kernel_read_file.c fs/kernel_file_read: Add "offset" arg for partial reads 2020-10-05 13:37:04 +02:00
libfs.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
locks.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
Makefile Char/Misc driver patches for 5.10-rc1 2020-10-15 10:01:51 -07:00
mbcache.c
mount.h proc/mounts: add cursor 2020-05-14 16:44:24 +02:00
mpage.c fs: convert mpage_readpages to mpage_readahead 2020-06-02 10:59:07 -07:00
namei.c fs: remove the unused SB_I_MULTIROOT flag 2020-09-24 13:43:38 -06:00
namespace.c Merge branch 'compat.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-12 16:44:57 -07:00
no-block.c
nsfs.c nsproxy: attach to namespaces via pidfds 2020-05-13 11:41:22 +02:00
open.c exec: move S_ISREG() check earlier 2020-08-12 10:58:01 -07:00
pipe.c Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-11 11:11:35 -07:00
pnode.c
pnode.h
posix_acl.c vfs: clean up posix_acl_permission() logic aroudn MAY_NOT_BLOCK 2020-06-08 11:04:19 -07:00
proc_namespace.c Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2020-06-04 13:54:34 -07:00
read_write.c Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-12 16:35:51 -07:00
readdir.c fs: remove ksys_getdents64 2020-07-31 08:16:00 +02:00
select.c pselect6() and friends: take handling the combined 6th/7th args into helper 2020-05-29 19:10:42 -04:00
seq_file.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
signalfd.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
splice.c Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-12 16:35:51 -07:00
stack.c
stat.c New code for 5.8: 2020-06-02 19:45:12 -07:00
statfs.c
super.c bdi: replace BDI_CAP_STABLE_WRITES with a queue and a sb flag 2020-09-24 13:43:39 -06:00
sync.c overlayfs update for 5.8 2020-06-09 15:40:50 -07:00
timerfd.c
userfaultfd.c A set of locking fixes and updates: 2020-08-10 19:07:44 -07:00
utimes.c fs: expose utimes_common 2020-07-31 08:16:01 +02:00
xattr.c fs/xattr.c: fix kernel-doc warnings for setxattr & removexattr 2020-10-13 18:38:27 -07:00