kernel-ark/fs
James Bottomley d1cabd6326 [PATCH] fix process crash caused by randomisation and 64k pages
This bug was seen on ppc64, but it could have occurred on any
architecture with a page size of 64k or above.  The problem is that in
fs/binfmt_elf.c:randomize_stack_top() randomizes the stack to within
0x7ff pages.  On 4k page machines, this is 8MB; on 64k page boxes, this
is 128MB.

The problem is that the new binary layout (selected in
arch_pick_mmap_layout) places the mapping segment 128MB or the stack
rlimit away from the top of the process memory, whichever is larger.  If
you chose an rlimit of less than 128MB (most defaults are in the 8Mb
range) then you can end up having your entire stack randomized away.

The fix is to make randomize_stack_top() only steal at most 8MB, which this
patch does.  However, I have to point out that even with this, your stack
rlimit might not be exactly what you get if it's > 128MB, because you're
still losing the random offset of up to 8MB.

The true fix should be to leave an explicit gap for the randomization plus
a buffer when determining mmap_base, but that would involve fixing all the
architectures.

Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-16 19:25:06 -07:00
..
9p 9p: implement optional loose read cache 2007-02-18 10:16:10 -06:00
adfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
affs [PATCH] affs: implement ->drop_inode 2007-02-20 17:10:15 -08:00
afs [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
autofs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
autofs4 [PATCH] autofs4: check for directory re-create in lookup 2007-02-20 17:10:15 -08:00
befs [PATCH] mark struct inode_operations const 1 2007-02-12 09:48:46 -08:00
bfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
cifs [PATCH] cifs endianness annotations 2007-03-14 15:27:50 -07:00
coda [PATCH] sysctl: remove insert_at_head from register_sysctl 2007-02-14 08:09:59 -08:00
configfs configfs: add missing mutex_unlock() 2007-03-14 14:37:21 -07:00
cramfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
debugfs debugfs: Remove misleading comments. 2007-02-16 15:19:17 -08:00
devpts [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
dlm [DLM] fs/dlm/user.c should #include "user.h" 2007-03-07 13:58:21 -05:00
ecryptfs [PATCH] eCryptfs: fix possible NULL ptr deref in ecryptfs_d_release() 2007-03-16 19:25:05 -07:00
efs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
exportfs
ext2 [PATCH] ext[234]: update documentation 2007-02-20 17:10:14 -08:00
ext3 [PATCH] ext[34]: EA block reference count racing fix 2007-03-01 14:53:38 -08:00
ext4 [PATCH] ext[34]: EA block reference count racing fix 2007-03-01 14:53:38 -08:00
fat [PATCH] FAT: DIO-write fallback to normal buffered 2007-02-20 17:10:14 -08:00
freevxfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
fuse [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
gfs2 [GFS2] Fix bz 229873, alternate test: assertion "!ip->i_inode.i_mapping->nrpages" failed 2007-03-07 14:03:53 -05:00
hfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
hfsplus [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
hostfs [PATCH] uml: hostfs: make hostfs= option work as a jail, as intended. 2007-03-08 07:38:21 -08:00
hpfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
hppfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
hugetlbfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
isofs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
jbd [PATCH] jbd: wait for already submitted t_sync_datalist buffer to complete 2006-12-22 08:55:51 -08:00
jbd2 [PATCH] jbd2: wait for already submitted t_sync_datalist buffer to complete 2006-12-07 08:39:42 -08:00
jffs2 [JFFS2] print a message when marking bad block 2007-03-09 12:29:39 +00:00
jfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy/jfs-2.6 2007-02-26 11:44:51 -08:00
lockd Replace remaining references to "driverfs" with "sysfs". 2007-02-17 19:13:42 +01:00
minix [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
msdos [PATCH] mark struct inode_operations const 2 2007-02-12 09:48:46 -08:00
ncpfs ncpfs: make sure server connection survives a kill 2007-03-06 13:26:27 +01:00
nfs [PATCH] nfs: nfs_getattr() can't call nfs_sync_mapping_range() for non-regular files 2007-03-16 19:25:06 -07:00
nfs_common
nfsd [PATCH] include of asm/pgtable.h in nfsfh is bogus 2007-03-14 15:27:49 -07:00
nls [PATCH] fs: make nls_cp936.c handle some U00XY characters and U20AC correctly 2006-12-07 08:39:46 -08:00
ntfs [PATCH] sysctl: remove the proc_dir_entry member for the sysctl tables 2007-02-14 08:10:00 -08:00
ocfs2 ocfs2_dlm: Add missing locks in dlm_empty_lockres 2007-03-14 14:37:35 -07:00
openpromfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
partitions [PATCH] change misleading EFI partition support description 2007-03-16 19:25:06 -07:00
proc [PATCH] sanitize security_getprocattr() API 2007-03-14 15:27:48 -07:00
qnx4 [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
ramfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
reiserfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
romfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
smbfs [PATCH] smbfs: double free memory corruption 2007-03-16 19:25:05 -07:00
sysfs [PATCH] sysfs: reinstate exclusion between method calls and attribute unregistration 2007-03-15 15:29:26 -07:00
sysv [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
udf [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
ufs [PATCH] ufs2: tindirect truncate fix 2007-03-16 19:25:03 -07:00
vfat [PATCH] mark struct inode_operations const 3 2007-02-12 09:48:46 -08:00
xfs [PATCH] xfs warning fix 2007-02-20 17:10:13 -08:00
aio.c [PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc(). 2007-02-11 10:51:27 -08:00
attr.c
bad_inode.c [PATCH] mark struct inode_operations const 1 2007-02-12 09:48:46 -08:00
binfmt_aout.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_elf_fdpic.c [PATCH] Remove final references to deprecated "MAP_ANON" page protection flag 2007-02-11 10:51:17 -08:00
binfmt_elf.c [PATCH] fix process crash caused by randomisation and 64k pages 2007-03-16 19:25:06 -07:00
binfmt_em86.c
binfmt_flat.c [PATCH] uclinux: correctly remap bin_fmtflat exe allocated mem regions 2007-02-09 10:45:33 -08:00
binfmt_misc.c [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
binfmt_script.c
binfmt_som.c
bio.c [PATCH] optimize o_direct on block devices 2006-12-13 09:05:50 -08:00
block_dev.c [PATCH] lockdep: annotate BLKPG_DEL_PARTITION 2007-02-20 17:10:16 -08:00
buffer.c [PATCH] fs: nobh_truncate_page() fix 2007-03-06 09:30:25 -08:00
char_dev.c [PATCH] rework reserved major handling 2007-02-20 17:10:13 -08:00
compat_ioctl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
compat.c [PATCH] Add epoll compat_ code to fs/compat.c 2007-03-08 07:38:22 -08:00
dcache.c Revert "[PATCH] Fix d_path for lazy unmounts" 2007-02-13 12:08:18 -08:00
dcookies.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
direct-io.c [PATCH] dio: lock refcount operations 2006-12-10 09:57:21 -08:00
dnotify.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
dquot.c [PATCH] sysctl: remove insert_at_head from register_sysctl 2007-02-14 08:09:59 -08:00
drop_caches.c [PATCH] remove invalidate_inode_pages() 2007-02-11 10:51:31 -08:00
eventpoll.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
exec.c [PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc(). 2007-02-11 10:51:27 -08:00
fcntl.c [PATCH] fdtable: Make fdarray and fdsets equal in size 2006-12-10 09:57:22 -08:00
fifo.c
file_table.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
file.c [PATCH] fdtable: Provide free_fdtable() wrapper 2006-12-22 08:55:50 -08:00
filesystems.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
fs-writeback.c Write back inode data pages even when the inode itself is locked 2007-01-26 12:53:20 -08:00
generic_acl.c
inode.c [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
inotify_user.c [PATCH] inotify: read return val fix 2007-02-12 09:48:28 -08:00
inotify.c
internal.h
ioctl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
ioprio.c [PATCH] pid: replace do/while_each_task_pid with do/while_each_pid_task 2007-02-12 09:48:32 -08:00
Kconfig Remove JFFS (version 1), as scheduled. 2007-02-17 16:10:59 -05:00
Kconfig.binfmt
libfs.c [PATCH] shmem and simple const super_operations 2007-03-05 07:57:51 -08:00
locks.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
Makefile Remove JFFS (version 1), as scheduled. 2007-02-17 16:10:59 -05:00
mbcache.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
mpage.c
namei.c [PATCH] __page_symlink retry loop error code fix 2007-02-16 08:13:56 -08:00
namespace.c [PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc(). 2007-02-11 10:51:27 -08:00
nfsctl.c
no-block.c
open.c [PATCH] fdtable: Make fdarray and fdsets equal in size 2006-12-10 09:57:22 -08:00
pipe.c [PATCH] AUDIT_FD_PAIR 2007-02-17 21:30:15 -05:00
pnode.c [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
pnode.h [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
posix_acl.c
quota_v1.c
quota_v2.c
quota.c
read_write.c [PATCH] FS: speed up rw_verify_area() 2007-02-12 09:48:29 -08:00
read_write.h
readdir.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
select.c [PATCH] fdtable: Make fdarray and fdsets equal in size 2006-12-10 09:57:22 -08:00
seq_file.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
splice.c [PATCH] constify pipe_buf_operations 2006-12-13 09:05:47 -08:00
stack.c [PATCH] fs/stack.c: Copy i_nlink after all other attributes are copied 2007-02-19 14:21:50 -08:00
stat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
super.c [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
sync.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
utimes.c
xattr_acl.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
xattr.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00