Kees Cook f6f8285132 pstore: pass allocated memory region back to caller ... The buf_lock cannot be held while populating the inodes, so make the backend pass forward an allocated and filled buffer instead. This solves the following backtrace. The effect is that "buf" is only ever used to notify the backends that something was written to it, and shouldn't be used in the read path. To replace the buf_lock during the read path, isolate the open/read/close loop with a separate mutex to maintain serialized access to the backend. Note that is is up to the pstore backend to cope if the (*write)() path is called in the middle of the read path. [ 59.691019] BUG: sleeping function called from invalid context at .../mm/slub.c:847 [ 59.691019] in_atomic(): 0, irqs_disabled(): 1, pid: 1819, name: mount [ 59.691019] Pid: 1819, comm: mount Not tainted 3.0.8 #1 [ 59.691019] Call Trace: [ 59.691019] [<810252d5>] __might_sleep+0xc3/0xca [ 59.691019] [<810a26e6>] kmem_cache_alloc+0x32/0xf3 [ 59.691019] [<810b53ac>] ? __d_lookup_rcu+0x6f/0xf4 [ 59.691019] [<810b68b1>] alloc_inode+0x2a/0x64 [ 59.691019] [<810b6903>] new_inode+0x18/0x43 [ 59.691019] [<81142447>] pstore_get_inode.isra.1+0x11/0x98 [ 59.691019] [<81142623>] pstore_mkfile+0xae/0x26f [ 59.691019] [<810a2a66>] ? kmem_cache_free+0x19/0xb1 [ 59.691019] [<8116c821>] ? ida_get_new_above+0x140/0x158 [ 59.691019] [<811708ea>] ? __init_rwsem+0x1e/0x2c [ 59.691019] [<810b67e8>] ? inode_init_always+0x111/0x1b0 [ 59.691019] [<8102127e>] ? should_resched+0xd/0x27 [ 59.691019] [<8137977f>] ? _cond_resched+0xd/0x21 [ 59.691019] [<81142abf>] pstore_get_records+0x52/0xa7 [ 59.691019] [<8114254b>] pstore_fill_super+0x7d/0x91 [ 59.691019] [<810a7ff5>] mount_single+0x46/0x82 [ 59.691019] [<8114231a>] pstore_mount+0x15/0x17 [ 59.691019] [<811424ce>] ? pstore_get_inode.isra.1+0x98/0x98 [ 59.691019] [<810a8199>] mount_fs+0x5a/0x12d [ 59.691019] [<810b9174>] ? alloc_vfsmnt+0xa4/0x14a [ 59.691019] [<810b9474>] vfs_kern_mount+0x4f/0x7d [ 59.691019] [<810b9d7e>] do_kern_mount+0x34/0xb2 [ 59.691019] [<810bb15f>] do_mount+0x5fc/0x64a [ 59.691019] [<810912fb>] ? strndup_user+0x2e/0x3f [ 59.691019] [<810bb3cb>] sys_mount+0x66/0x99 [ 59.691019] [<8137b537>] sysenter_do_call+0x12/0x26 Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Luck <tony.luck@intel.com>		2011-11-17 12:58:07 -08:00
..
9p	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
adfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
affs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
afs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
autofs4	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
befs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
bfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
btrfs	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs	2011-11-11 23:47:06 -02:00
cachefiles	kill useless checks for sb->s_op == NULL	2011-07-20 01:44:21 -04:00
ceph	ceph/super.c: quiet sparse noise	2011-11-05 21:10:12 -07:00
cifs	Merge git://git.samba.org/sfrench/cifs-2.6	2011-11-07 09:56:22 -08:00
coda	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
configfs	doc: fix broken references	2011-09-27 18:08:04 +02:00
cramfs	cramfs: get_cramfs_inode() returns ERR_PTR() on failure	2011-07-17 23:22:02 -04:00
debugfs	debugfs: Fix a comment mistake	2011-08-22 17:41:48 -07:00
devpts	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
dlm	Merge branch 'for-3.1' of git://linux-nfs.org/~bfields/linux	2011-07-25 22:49:19 -07:00
ecryptfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
efs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
exofs	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
exportfs
ext2	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue	2011-11-02 11:41:01 -07:00
ext3	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue	2011-11-02 11:41:01 -07:00
ext4	Merge branch 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux	2011-11-06 19:02:23 -08:00
fat	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
freevxfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
fscache	FS-Cache: Fix __fscache_uncache_all_inode_pages()'s outer loop	2011-07-21 10:59:16 -07:00
fuse	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
gfs2	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
hfs	hfs: add sanity check for file name length	2011-11-15 14:29:42 -02:00
hfsplus	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
hostfs	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue	2011-11-02 11:41:01 -07:00
hpfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
hppfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
hugetlbfs	filesystems: add missing nlink wrappers	2011-11-02 12:53:43 +01:00
isofs	Merge branch 'akpm' (Andrew's incoming - part two)	2011-11-02 16:07:27 -07:00
jbd	jbd/jbd2: validate sb->s_first in journal_get_superblock()	2011-11-01 19:04:59 -04:00
jbd2	jbd2: Unify log messages in jbd2 code	2011-11-01 19:09:18 -04:00
jffs2	Merge git://git.infradead.org/mtd-2.6	2011-11-07 09:11:16 -08:00
jfs	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
lockd	SUNRPC: Replace svc_addr_u by sockaddr_storage	2011-09-14 08:21:48 -04:00
logfs	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
minix	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
ncpfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
nfs	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
nfs_common
nfsd	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
nilfs2	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
nls
notify	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
ntfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
ocfs2	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
omfs	omfs: fix (mode & S_IFDIR) abuse	2011-07-26 13:05:28 -04:00
openpromfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
partitions	treewide: use __printf not __attribute__((format(printf,...)))	2011-10-31 17:30:54 -07:00
proc	Revert "proc: fix races against execve() of /proc/PID/fd**"	2011-11-09 18:16:00 -05:00
pstore	pstore: pass allocated memory region back to caller	2011-11-17 12:58:07 -08:00
qnx4	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
quota	Merge branch 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux	2011-11-06 19:02:23 -08:00
ramfs	ramfs: remove module leftovers	2011-11-02 16:06:58 -07:00
reiserfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
romfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
squashfs	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next	2011-11-04 16:48:37 -07:00
sysfs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
sysv	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
ubifs	Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6	2011-11-07 08:52:19 -08:00
udf	Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue	2011-11-02 11:41:01 -07:00
ufs	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
xfs	xfs: fix force shutdown handling in xfs_end_io	2011-11-08 10:48:23 -06:00
aio.c	aio: allocate kiocbs in batches	2011-11-02 16:07:03 -07:00
anon_inodes.c	vfs: dont chain pipe/anon/socket on superblock s_inodes list	2011-07-26 12:57:09 -04:00
attr.c	Merge branch 'next-evm' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/ima-2.6 into next	2011-08-09 10:31:03 +10:00
bad_inode.c	fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers	2011-07-20 20:47:59 -04:00
binfmt_aout.c
binfmt_elf_fdpic.c	consolidate BINPRM_FLAGS_ENFORCE_NONDUMP handling	2011-07-20 01:43:10 -04:00
binfmt_elf.c	binfmt_elf: fix PIE execution with randomization disabled	2011-11-02 16:06:58 -07:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c	filesystems: add missing nlink wrappers	2011-11-02 12:53:43 +01:00
binfmt_script.c
binfmt_som.c
bio-integrity.c	fs: add export.h to files using EXPORT_SYMBOL/THIS_MODULE macros	2011-10-31 19:30:31 -04:00
bio.c	block: Remove the control of complete cpu from bio.	2011-10-24 16:11:30 +02:00
block_dev.c	Merge branch 'for-3.2/drivers' of git://git.kernel.dk/linux-block	2011-11-04 17:22:14 -07:00
buffer.c	Merge branch 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux	2011-11-06 19:02:23 -08:00
char_dev.c
compat_binfmt_elf.c
compat_ioctl.c	compat_ioctl: add compat handler for PPPIOCGL2TPSTATS	2011-08-07 22:24:41 -07:00
compat.c	Cross Memory Attach	2011-10-31 17:30:44 -07:00
dcache.c	vfs: d_invalidate() should leave mountpoints alone	2011-11-07 10:54:10 -08:00
dcookies.c
direct-io.c	direct-io: merge direct_io_walker into __blockdev_direct_IO	2011-10-28 14:58:58 +02:00
drop_caches.c
eventfd.c
eventpoll.c	epoll: fix spurious lockdep warnings	2011-10-31 17:30:57 -07:00
exec.c	oom: remove oom_disable_count	2011-10-31 17:30:45 -07:00
fcntl.c
fhandle.c
fifo.c
file_table.c	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
file.c
filesystems.c
fs_struct.c
fs-writeback.c	writeback: Add a 'reason' to wb_writeback_work	2011-10-31 00:33:36 +08:00
generic_acl.c	switch posix_acl_equiv_mode() to umode_t *	2011-08-01 02:10:06 -04:00
inode.c	vfs: protect i_nlink	2011-11-02 12:53:43 +01:00
internal.h	superblock: move pin_sb_for_writeback() to fs/super.c	2011-07-20 01:44:38 -04:00
ioctl.c
ioprio.c	fs: add export.h to files using EXPORT_SYMBOL/THIS_MODULE macros	2011-10-31 19:30:31 -04:00
Kconfig	tmpfs: add "tmpfs" to the Kconfig prompt to make it obvious.	2011-10-31 17:30:45 -07:00
Kconfig.binfmt
libfs.c	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
locks.c	Merge branch 'for-3.2' of git://linux-nfs.org/~bfields/linux	2011-10-25 15:42:01 +02:00
Makefile	fs/Makefile: Stupid typo breakage of exofs inclusion	2011-10-27 08:36:51 +02:00
mbcache.c
mpage.c
namei.c	VFS: we need to set LOOKUP_JUMPED on mountpoint crossing	2011-11-07 14:58:06 -08:00
namespace.c	vfs: add "device" tag to /proc/self/mountstats	2011-10-28 13:55:08 +02:00
no-block.c
open.c	leases: fix write-open/read-lease race	2011-10-28 14:59:00 +02:00
pipe.c	fs/pipe.c: add ->statfs callback for pipefs	2011-10-31 17:30:51 -07:00
pnode.c
pnode.h
posix_acl.c	vfs: pass all mask flags check_acl and posix_acl_permission	2011-10-28 14:58:54 +02:00
read_write.c	Cross Memory Attach	2011-10-31 17:30:44 -07:00
read_write.h
readdir.c
select.c
seq_file.c
signalfd.c
splice.c	tmpfs: clone shmem_file_splice_read()	2011-07-25 20:57:11 -07:00
stack.c	filesystems: add set_nlink()	2011-11-02 12:53:43 +01:00
stat.c	readlinkat: ensure we return ENOENT for the empty pathname for normal lookups	2011-11-02 12:53:42 +01:00
statfs.c	VFS: fix statfs() automounter semantics regression	2011-11-04 18:15:59 -07:00
super.c	vfs: ignore error on forced remount	2011-11-02 12:53:42 +01:00
sync.c	writeback: Add a 'reason' to wb_writeback_work	2011-10-31 00:33:36 +08:00
timerfd.c
utimes.c
xattr_acl.c
xattr.c	evm: evm_inode_post_removexattr	2011-07-18 12:29:43 -04:00