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Pratyush Anand 464920104b /proc/kcore: update physical address for kcore ram and text 
Currently all the p_paddr of PT_LOAD headers are assigned to 0, which is
not true and could be misleading, since 0 is a valid physical address.

User space tools like makedumpfile needs to know physical address for
PT_LOAD segments of direct mapped regions.  Therefore this patch updates
paddr for such regions.  It also sets an invalid paddr (-1) for other
regions, so that user space tool can know whether a physical address
provided in PT_LOAD is correct or not.

I do not know why it was 0, which is a valid physical address.  But
certainly, it might break some user space tools, and those need to be
fixed.  For example, see following code from kexec-tools

kexec/kexec-elf.c:build_mem_phdrs()

                    if ((phdr->p_paddr + phdr->p_memsz) < phdr->p_paddr) {
                            /* The memory address wraps */
                            if (probe_debug) {
                                    fprintf(stderr, "ELF address wrap around\n");
                            }
                            return -1;
                    }

We do not need to perform above check for an invalid physical address.

I think, kexec-tools and makedumpfile will need fixup.  I already have
those fixup which will be sent upstream once this patch makes through.
Pro with this approach is that, it will help to calculate variable like
page_offset, phys_base from PT_LOAD even when they are randomized and
therefore will reduce many variable and version specific values in user
space tools.

Having an ASLR offset information can help to translate an identity
mapped virtual address to a physical address.  But that would be an
additional field in PT_LOAD header structure and an arch dependent
value.

Moreover, sending a valid physical address like 0 does not seem right.
So, IMHO it is better to fix that and send valid physical address when
available (identity mapped).

Link: http://lkml.kernel.org/r/f951340d2917cdd2a329fae9837a83f2059dc3b2.1485318868.git.panand@redhat.com
Signed-off-by: Pratyush Anand <panand@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:45 -08:00
..
9p mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
adfs
affs
afs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
autofs4 autofs: take more care to not update last_used on path walk 2017-02-27 18:43:45 -08:00
befs befs: add NFS export support 2016-12-22 11:25:24 +00:00
bfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
btrfs Merge branch 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-02-25 14:53:58 -08:00
cachefiles
ceph mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
cifs mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
coda
configfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
cramfs
crypto fscrypt: properly declare on-stack completion 2017-02-06 23:45:28 -05:00
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
devpts
dlm ktime: Get rid of ktime_equal() 2016-12-25 17:21:23 +01:00
ecryptfs
efivarfs
efs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
exofs locking/atomic, kref: Add kref_read() 2017-01-14 11:37:18 +01:00
exportfs
ext2 mm: replace FAULT_FLAG_SIZE with parameter to huge_fault 2017-02-24 17:46:54 -08:00
ext4 mm: replace FAULT_FLAG_SIZE with parameter to huge_fault 2017-02-24 17:46:54 -08:00
f2fs mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
fat
freevxfs
fscache fscache: Fix dead object requeue 2017-01-31 13:23:09 -05:00
fuse mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
gfs2 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
hfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
hfsplus hfsplus: atomically read inode size 2017-02-27 18:43:45 -08:00
hostfs
hpfs
hugetlbfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
isofs
jbd2 For this cycle we add support for the shutdown ioctl, which is 2017-02-20 18:24:39 -08:00
jffs2
jfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
kernfs mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
lockd
minix
ncpfs mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
nfs mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
nfs_common
nfsd driver core patches for 4.11-rc1 2017-02-22 11:44:32 -08:00
nilfs2 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
nls
notify Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
ntfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
ocfs2 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
omfs
openpromfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
orangefs Linux 4.10 2017-02-25 11:12:48 -05:00
overlayfs ovl: fix possible use after free on redirect dir lookup 2017-01-18 15:19:54 +01:00
proc /proc/kcore: update physical address for kcore ram and text 2017-02-27 18:43:45 -08:00
pstore fs/pstore: fs/squashfs: change usage of LZ4 to work with new LZ4 version 2017-02-24 17:46:57 -08:00
qnx4
qnx6
quota Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2016-12-19 08:23:53 -08:00
ramfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
reiserfs fs/reiserfs: atomically read inode size 2017-02-27 18:43:45 -08:00
romfs romfs: use different way to generate fsid for BLOCK or MTD 2017-01-24 16:26:14 -08:00
squashfs fs/pstore: fs/squashfs: change usage of LZ4 to work with new LZ4 version 2017-02-24 17:46:57 -08:00
sysfs
sysv
tracefs
ubifs mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
udf udf: simplify udf_ioctl() 2017-02-03 16:24:18 +01:00
ufs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
xfs mm: replace FAULT_FLAG_SIZE with parameter to huge_fault 2017-02-24 17:46:54 -08:00
aio.c userfaultfd: non-cooperative: add event for memory unmaps 2017-02-24 17:46:55 -08:00
anon_inodes.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
attr.c
bad_inode.c
binfmt_aout.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
binfmt_elf.c powerpc: do not make the entire heap executable 2017-02-22 16:41:29 -08:00
binfmt_elf_fdpic.c fs/binfmt: Convert obsolete cputime type to nsecs 2017-02-01 09:13:51 +01:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c
binfmt_script.c
block_dev.c block: Revalidate i_bdev reference in bd_aquire() 2017-02-21 12:51:54 -07:00
buffer.c clean_bdev_aliases: Prevent cleaning blocks that are not in block range 2017-01-02 09:35:14 -07:00
char_dev.c
compat.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
compat_binfmt_elf.c fs/binfmt: Convert obsolete cputime type to nsecs 2017-02-01 09:13:51 +01:00
compat_ioctl.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
coredump.c coredump: Ensure proper size of sparse core files 2017-01-14 19:32:40 -05:00
dax.c mm,fs,dax: mark dax_iomap_pmd_fault as const 2017-02-27 18:43:45 -08:00
dcache.c mnt: Protect the mountpoint hashtable with mount_lock 2017-01-10 13:34:43 +13:00
dcookies.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
direct-io.c do_direct_IO: Use inode->i_blkbits to compute block count to be cleaned 2017-01-10 13:29:54 -07:00
drop_caches.c
eventfd.c
eventpoll.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
exec.c vfs: Use upper filesystem inode in bprm_fill_uid() 2017-02-14 20:51:12 +13:00
fcntl.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
fhandle.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
file.c
file_table.c
filesystems.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
fs-writeback.c
fs_pin.c
fs_struct.c
inode.c
internal.h iomap: constify struct iomap_ops 2017-01-30 16:32:25 -08:00
ioctl.c
iomap.c mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
Kconfig dax: fix build warnings with FS_DAX and !FS_IOMAP 2017-01-24 16:26:14 -08:00
Kconfig.binfmt
libfs.c libfs: Modify mount_pseudo_xattr to be clear it is not a userspace mount 2017-01-10 13:34:55 +13:00
locks.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
Makefile
mbcache.c
mount.h mnt: Tuck mounts under others instead of creating shadow/side mounts. 2017-02-04 00:01:06 +13:00
mpage.c
namei.c fs: Better permission checking for submounts 2017-02-02 04:36:12 +13:00
namespace.c mnt: Tuck mounts under others instead of creating shadow/side mounts. 2017-02-04 00:01:06 +13:00
no-block.c
nsfs.c nsfs: Add an ioctl() to return owner UID of a userns 2017-02-03 14:35:43 +13:00
open.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
pipe.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
pnode.c mnt: Tuck mounts under others instead of creating shadow/side mounts. 2017-02-04 00:01:06 +13:00
pnode.h mnt: Tuck mounts under others instead of creating shadow/side mounts. 2017-02-04 00:01:06 +13:00
posix_acl.c tmpfs: clear S_ISGID when setting posix ACLs 2017-01-10 01:29:48 -05:00
proc_namespace.c
read_write.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
readdir.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
select.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
seq_file.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
signalfd.c
splice.c vfs: fix uninitialized flags in splice_to_pipe() 2017-02-16 09:09:02 -08:00
stack.c
stat.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
statfs.c
super.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
sync.c
timerfd.c timerfd: Protect the might cancel mechanism proper 2017-02-10 11:15:09 +01:00
userfaultfd.c userfaultfd_copy: return -ENOSPC in case mm has gone 2017-02-24 17:46:55 -08:00
utimes.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
xattr.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00