linux/drivers/acpi
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
..
acpica Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2011-11-07 10:13:52 -08:00
apei pstore: pass allocated memory region back to caller 2011-11-17 12:58:07 -08:00
ac.c treewide: fix potentially dangerous trailing ';' in #defined values/expressions 2011-07-21 14:10:00 +02:00
acpi_ipmi.c IPMI/ACPI: Add the IPMI opregion driver to enable ACPI to access BMC controller 2010-12-14 00:22:14 -05:00
acpi_memhotplug.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
acpi_pad.c ACPI: minor printk format change in acpi_pad 2011-03-23 01:36:45 -04:00
atomicio.c Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2011-11-07 10:13:52 -08:00
battery.c Merge branch 'battery' into release 2011-08-05 22:16:42 -04:00
blacklist.c acpi: delete module.h include from files explicitly not needing it 2011-10-31 19:30:33 -04:00
bus.c ACPI: Drop ACPI_NO_HARDWARE_INIT 2011-11-06 20:32:31 -05:00
button.c ACPI button: remove unused procfs I/F 2011-03-22 23:20:35 -04:00
cm_sbs.c
container.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
custom_method.c ACPI: Split out custom_method functionality into an own driver 2011-05-29 01:50:40 -04:00
debugfs.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
dock.c ACPI: constify ops structs 2011-07-16 18:36:17 -04:00
ec.c Merge branch 'ec-cleanup' into release 2011-05-29 04:40:39 -04:00
ec_sys.c acpi: add module.h to files implicitly using/relying on it. 2011-10-31 19:30:32 -04:00
event.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
fan.c ACPI: constify ops structs 2011-07-16 18:36:17 -04:00
glue.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
hed.c ACPI Hardware Error Device (PNP0C33) support 2010-05-19 22:40:24 -04:00
internal.h ACPI: Cleanup custom_method debug stuff 2011-05-29 01:50:04 -04:00
Kconfig Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-05-29 11:19:16 -07:00
Makefile Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-05-29 11:19:16 -07:00
numa.c x86-64, NUMA: Unify {acpi|amd}_{numa_init|scan_nodes}() arguments and return values 2011-02-16 12:13:06 +01:00
nvs.c ACPI / PM: Use existing ACPI iomaps for NVS save/restore (v2) 2011-02-24 19:58:42 +01:00
osl.c PCI hotplug: acpiphp: Prevent deadlock on PCI-to-PCI bridge remove 2011-10-14 09:05:31 -07:00
pci_bind.c PCI / ACPI / PM: Platform support for PCI PME wake-up 2010-02-22 16:21:02 -08:00
pci_irq.c ACPI: fix CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS 2011-07-16 18:24:17 -04:00
pci_link.c ACPI: Use syscore_ops instead of sysdev class and sysdev 2011-03-18 18:22:21 -04:00
pci_root.c ACPI: fix 80 char overflow 2011-07-14 00:14:05 -04:00
pci_slot.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
power.c ACPI / PM: Check status of power resources under mutexes 2011-01-12 05:05:39 -05:00
proc.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
processor_core.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
processor_driver.c cpuidle: Single/Global registration of idle states 2011-11-06 21:13:58 -05:00
processor_idle.c ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression) 2011-11-12 21:30:14 -02:00
processor_perflib.c [CPUFREQ] use dynamic debug instead of custom infrastructure 2011-05-04 11:50:57 -04:00
processor_thermal.c ACPI: constify ops structs 2011-07-16 18:36:17 -04:00
processor_throttling.c Merge branch 'x86/urgent' into x86-mm 2011-05-02 14:16:47 +02:00
reboot.c ACPI: Make sure the FADT is at least rev 2 before using the reset register 2011-03-22 23:52:49 -04:00
sbs.c Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-08-02 21:17:02 -10:00
sbshc.c acpi: add module.h to files implicitly using/relying on it. 2011-10-31 19:30:32 -04:00
sbshc.h
scan.c ACPI: use kstrdup() 2011-11-06 19:13:44 -05:00
sleep.c ACPI / PM: Add Sony VPCEB17FX to nonvs blacklist 2011-11-04 22:28:09 +01:00
sleep.h ACPI: static sleep_states[] and acpi_gts_bfs_check 2010-10-19 13:44:37 -04:00
sysfs.c ACPI: Export FADT pm_profile integer value to userspace 2011-11-06 20:48:42 -05:00
tables.c ACPI: delete the "acpi=ht" boot option 2010-03-14 20:58:38 -04:00
thermal.c ACPI: constify ops structs 2011-07-16 18:36:17 -04:00
utils.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
video.c Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-08-02 21:17:02 -10:00
video_detect.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
wakeup.c ACPI / Wakeup: Enable button GPEs unconditionally during initialization 2011-02-12 01:39:53 +01:00