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
acpi_ipmi.c
acpi_memhotplug.c
acpi_pad.c
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
cm_sbs.c
container.c
custom_method.c
debugfs.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
dock.c
ec.c
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
glue.c acpi: add export.h to files using THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:30:34 -04:00
hed.c
internal.h
Kconfig
Makefile
numa.c
nvs.c
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_irq.c
pci_link.c
pci_root.c
pci_slot.c
power.c
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
processor_thermal.c
processor_throttling.c
reboot.c
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
sysfs.c ACPI: Export FADT pm_profile integer value to userspace 2011-11-06 20:48:42 -05:00
tables.c
thermal.c
utils.c
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