linux/lib
James Bottomley c7ae10ceba klist: fix starting point removed bug in klist iterators
[ Upstream commit 00cd29b799 ]

The starting node for a klist iteration is often passed in from
somewhere way above the klist infrastructure, meaning there's no
guarantee the node is still on the list.  We've seen this in SCSI where
we use bus_find_device() to iterate through a list of devices.  In the
face of heavy hotplug activity, the last device returned by
bus_find_device() can be removed before the next call.  This leads to

Dec  3 13:22:02 localhost kernel: WARNING: CPU: 2 PID: 28073 at include/linux/kref.h:47 klist_iter_init_node+0x3d/0x50()
Dec  3 13:22:02 localhost kernel: Modules linked in: scsi_debug x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel joydev iTCO_wdt dcdbas ipmi_devintf acpi_power_meter iTCO_vendor_support ipmi_si imsghandler pcspkr wmi acpi_cpufreq tpm_tis tpm shpchp lpc_ich mfd_core nfsd nfs_acl lockd grace sunrpc tg3 ptp pps_core
Dec  3 13:22:02 localhost kernel: CPU: 2 PID: 28073 Comm: cat Not tainted 4.4.0-rc1+ #2
Dec  3 13:22:02 localhost kernel: Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013
Dec  3 13:22:02 localhost kernel: ffffffff81a20e77 ffff880613acfd18 ffffffff81321eef 0000000000000000
Dec  3 13:22:02 localhost kernel: ffff880613acfd50 ffffffff8107ca52 ffff88061176b198 0000000000000000
Dec  3 13:22:02 localhost kernel: ffffffff814542b0 ffff880610cfb100 ffff88061176b198 ffff880613acfd60
Dec  3 13:22:02 localhost kernel: Call Trace:
Dec  3 13:22:02 localhost kernel: [<ffffffff81321eef>] dump_stack+0x44/0x55
Dec  3 13:22:02 localhost kernel: [<ffffffff8107ca52>] warn_slowpath_common+0x82/0xc0
Dec  3 13:22:02 localhost kernel: [<ffffffff814542b0>] ? proc_scsi_show+0x20/0x20
Dec  3 13:22:02 localhost kernel: [<ffffffff8107cb4a>] warn_slowpath_null+0x1a/0x20
Dec  3 13:22:02 localhost kernel: [<ffffffff8167225d>] klist_iter_init_node+0x3d/0x50
Dec  3 13:22:02 localhost kernel: [<ffffffff81421d41>] bus_find_device+0x51/0xb0
Dec  3 13:22:02 localhost kernel: [<ffffffff814545ad>] scsi_seq_next+0x2d/0x40
[...]

And an eventual crash. It can actually occur in any hotplug system
which has a device finder and a starting device.

We can fix this globally by making sure the starting node for
klist_iter_init_node() is actually a member of the list before using it
(and by starting from the beginning if it isn't).

Reported-by: Ewan D. Milne <emilne@redhat.com>
Tested-by: Ewan D. Milne <emilne@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
History 2016-03-02 15:19:17 -05:00
..
fonts fonts: Add 6x10 font 2014-10-09 11:35:48 +03:00
lz4 LZ4 : fix the data abort issue 2015-03-28 09:33:25 -04:00
lzo lzo: check for length overrun in variable length encoding. 2014-09-28 11:08:01 +02:00
mpi MPILIB: add module description and license 2013-09-25 17:17:01 +01:00
raid6 lib/raid6: Add log level to printks 2014-10-14 13:08:29 +11:00
reed_solomon lib: Remove unnecessary inclusions of asm/semaphore.h 2008-04-18 22:17:17 -04:00
xz lib/xz: enable all filters by default in Kconfig 2014-06-04 16:54:18 -07:00
zlib_deflate zlib: clean up some dead code 2014-08-06 18:01:24 -07:00
zlib_inflate zlib: clean up some dead code 2014-08-06 18:01:24 -07:00
.gitignore X.509: Implement simple static OID registry 2012-10-08 13:50:18 +10:30
argv_split.c argv_split(): teach it to handle mutable strings 2013-04-29 18:28:19 -07:00
asn1_decoder.c lib/asn1_decoder.c: kernel-doc warning fix 2014-06-04 16:54:19 -07:00
assoc_array.c KEYS: Fix termination condition in assoc array garbage collection 2014-09-12 22:34:31 +10:00
atomic64.c locking,arch: Rewrite generic atomic support 2014-08-14 12:48:14 +02:00
atomic64_test.c lib/atomic64_test.c: convert printk(KERN_INFO to pr_info 2014-06-04 16:54:19 -07:00
audit.c audit: Add generic compat syscall support 2014-03-20 10:11:35 -04:00
average.c lib: Ensure EWMA does not store wrong intermediate values 2014-01-16 23:46:06 -08:00
bcd.c usb/core: use bin2bcd() for bcdDevice in RH 2012-09-10 11:13:16 -07:00
bch.c lib: add shared BCH ECC library 2011-03-11 14:25:50 +00:00
bitmap.c __bitmap_parselist: fix bug in empty string handling 2015-08-04 14:36:14 -04:00
bitrev.c lib: export bitrev16 2008-06-06 11:29:10 -07:00
bsearch.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
btree.c lib/btree.c: fix leak of whole btree nodes 2014-06-04 16:54:18 -07:00
bug.c lib/bug.c: convert printk to pr_foo() 2014-06-04 16:54:19 -07:00
build_OID_registry X.509: do not emit any informational output 2013-06-19 17:54:06 +02:00
bust_spinlocks.c printk: Provide a wake_up_klogd() off-case 2013-03-22 16:41:20 -07:00
check_signature.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
checksum.c lib/checksum.c: fix build for generic csum_tcpudp_nofold 2015-02-11 15:00:55 +08:00
clz_ctz.c lib/clz_ctz.c: add prototype declarations in lib/clz_ctz.c 2014-04-03 16:21:12 -07:00
clz_tab.c lib: Fix multiple definitions of clz_tab 2012-02-02 10:34:23 +11:00
cmdline.c lib: Add a generic cmdline parse function parse_option_str 2014-10-03 18:40:58 +01:00
compat_audit.c audit: Add generic compat syscall support 2014-03-20 10:11:35 -04:00
cordic.c Docs: wording: functions -> algorithm 2011-10-29 21:20:22 +02:00
cpu-notifier-error-inject.c cpu: rewrite cpu-notifier-error-inject module 2012-07-30 17:25:22 -07:00
cpu_rmap.c Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
cpumask.c lib/cpumask: cpumask_set_cpu_local_first to use all cores when numa node is not defined 2014-07-02 18:29:23 -07:00
crc-ccitt.c [PATCH] kernel-doc for lib/crc*.c 2006-06-25 10:01:20 -07:00
crc-itu-t.c CRC ITU-T V.41 2007-05-10 18:24:13 +02:00
crc-t10dif.c crypto: crct10dif - Add fallback for broken initrds 2013-09-12 15:31:34 +10:00
crc7.c lib/crc7: Shift crc7() output left 1 bit 2014-05-16 14:26:52 -04:00
crc8.c lib: crc8: add new library module providing crc8 algorithm 2011-06-03 15:01:06 -04:00
crc16.c [PATCH] kernel-doc for lib/crc*.c 2006-06-25 10:01:20 -07:00
crc32.c lib: crc32: Add some additional __pure annotations 2014-06-25 16:04:00 -07:00
crc32defs.h crc32: select an algorithm via Kconfig 2012-03-23 16:58:38 -07:00
ctype.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
debug_locks.c mutex: Add support for wound/wait style locks 2013-06-26 12:10:56 +02:00
debugobjects.c lib/debugobjects.c: convert printk(KERN_DEBUG to pr_debug 2014-06-04 16:53:53 -07:00
dec_and_lock.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
decompress.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_bunzip2.c decompress_bunzip2: off by one in get_next_block() 2015-01-27 08:29:45 -08:00
decompress_inflate.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unlz4.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unlzma.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unlzo.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unxz.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
devres.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-08-05 17:46:42 -07:00
digsig.c lib/digsig.c: kernel-doc warning fixes 2014-06-04 16:54:19 -07:00
div64.c math64: New separate div64_u64_rem helper 2013-08-23 09:02:14 -04:00
dma-debug.c dma-debug: switch check from _text to _stext 2016-02-09 22:57:07 -05:00
dump_stack.c dump_stack: avoid potential deadlocks 2016-02-15 15:42:41 -05:00
dynamic_debug.c lib/dynamic_debug.c: use seq_open_private() instead of seq_open() 2014-10-14 02:18:14 +02:00
dynamic_queue_limits.c bql: Avoid possible inconsistent calculation. 2012-05-31 18:18:17 -04:00
earlycpio.c earlycpio.c: Fix the confusing comment of find_cpio_data(). 2013-08-14 23:24:01 +02:00
extable.c module: trim exception table on init free. 2009-06-12 21:47:04 +09:30
fault-inject.c debugfs: add get/set for atomic types 2013-06-03 13:55:01 -07:00
fdt.c of/lib: Allow scripts/dtc/libfdt to be used from kernel code 2012-07-23 13:54:52 +01:00
fdt_empty_tree.c lib: add fdt_empty_tree.c 2014-04-30 19:49:37 +01:00
fdt_ro.c of/lib: Allow scripts/dtc/libfdt to be used from kernel code 2012-07-23 13:54:52 +01:00
fdt_rw.c of/lib: Allow scripts/dtc/libfdt to be used from kernel code 2012-07-23 13:54:52 +01:00
fdt_strerror.c of/lib: Allow scripts/dtc/libfdt to be used from kernel code 2012-07-23 13:54:52 +01:00
fdt_sw.c of/lib: Allow scripts/dtc/libfdt to be used from kernel code 2012-07-23 13:54:52 +01:00
fdt_wip.c of/lib: Allow scripts/dtc/libfdt to be used from kernel code 2012-07-23 13:54:52 +01:00
find_last_bit.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
find_next_bit.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
flex_array.c reciprocal_divide: update/correction of the algorithm 2014-01-21 23:17:20 -08:00
flex_proportions.c proportions: add @gfp to init functions 2014-09-08 09:51:30 +09:00
gcd.c lib/gcd.c: prevent possible div by 0 2012-10-06 03:04:57 +09:00
gen_crc32table.c sections: fix const sections for crc32 table 2012-10-06 03:04:46 +09:00
genalloc.c lib/genalloc.c: export devm_gen_pool_create() for modules 2014-12-03 09:36:04 -08:00
glob.c lib/glob.c: add CONFIG_GLOB_SELFTEST 2014-08-06 18:01:25 -07:00
halfmd4.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
hash.c lib: hash: follow-up fixups for arch hash 2013-12-19 00:14:53 -05:00
hexdump.c Provide a binary to hex conversion function 2014-09-16 17:36:01 +01:00
hweight.c Make ARCH_HAS_FAST_MULTIPLIER a real config variable 2014-09-13 11:14:53 -07:00
idr.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2014-10-07 21:16:26 -04:00
inflate.c MN10300: Don't try and #include <linux/slab.h> in lib/inflate.c from bootloader 2010-08-12 09:51:35 -07:00
int_sqrt.c lib/int_sqrt.c: optimize square root algorithm 2013-04-29 18:28:19 -07:00
interval_tree.c lib: Export interval_tree 2014-05-05 09:09:14 +02:00
interval_tree_test.c lib: Export interval_tree 2014-05-05 09:09:14 +02:00
iomap.c Kconfig: rename HAS_IOPORT to HAS_IOPORT_MAP 2014-04-07 16:36:11 -07:00
iomap_copy.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
iommu-helper.c The following text was taken from the original review request: 2012-03-24 10:24:31 -07:00
ioremap.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
iovec.c iovec: make sure the caller actually wants anything in memcpy_fromiovecend 2014-08-02 15:25:21 -07:00
irq_regs.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
is_single_threaded.c kernel: is_current_single_threaded: don't use ->mmap_sem 2009-07-17 09:11:31 +10:00
jedec_ddr_data.c ddr: add LPDDR2 data from JESD209-2 2012-05-02 00:04:06 -07:00
kasprintf.c lib/kasprintf.c: use kmalloc_track_caller() to get accurate traces for kvasprintf 2012-10-11 08:50:15 +09:00
Kconfig Make ARCH_HAS_FAST_MULTIPLIER a real config variable 2014-09-13 11:14:53 -07:00
Kconfig.debug lib: rename TEST_MODULE to TEST_LKM 2014-10-14 02:18:14 +02:00
Kconfig.kgdb treewide: Fix typo in printk 2013-06-18 13:48:45 +02:00
Kconfig.kmemcheck kmemcheck: depend on HAVE_ARCH_KMEMCHECK 2009-07-01 22:28:44 +02:00
kfifo.c kfifo: use BUG_ON 2014-08-08 15:57:25 -07:00
klist.c klist: fix starting point removed bug in klist iterators 2016-03-02 15:19:17 -05:00
kobject.c sysfs, kobject: add sysfs wrapper for kernfs_enable_ns() 2014-02-07 16:08:57 -08:00
kobject_uevent.c kobject: Make support for uevent_helper optional. 2014-04-25 12:00:49 -07:00
kstrtox.c lib/kstrtox.c: remove redundant cleanup 2014-01-23 16:36:57 -08:00
kstrtox.h lib/kstrtox: common code between kstrto*() and simple_strto*() functions 2011-10-31 17:30:56 -07:00
lcm.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
libcrc32c.c crypto: crc32c - Fix crc32c soft dependency 2016-02-09 22:57:34 -05:00
list_debug.c rcu: Fix broken strings in RCU's source code. 2012-07-06 06:01:49 -07:00
list_sort.c lib/list_sort.c: convert to pr_foo 2014-08-06 18:01:25 -07:00
llist.c llists-move-llist_reverse_order-from-raid5-to-llistc-fix 2013-11-15 09:32:22 +09:00
locking-selftest-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-mutex.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rlock.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-rsem.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-spin.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock-hardirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock-softirq.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wlock.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest-wsem.h [PATCH] lockdep: locking API self tests 2006-07-03 15:27:03 -07:00
locking-selftest.c locking/lockdep: Revert qrwlock recusive stuff 2014-10-03 06:09:30 +02:00
lockref.c arch, locking: Ciao arch_mutex_cpu_relax() 2014-07-17 12:32:47 +02:00
lru_cache.c drbd: debugfs: add per volume oldest_requests 2014-07-10 18:35:19 +02:00
Makefile reciprocal_div: objects with exported symbols should be obj-y rather than lib-y 2014-11-16 14:18:53 -05:00
md5.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
memory-notifier-error-inject.c memory: memory notifier error injection module 2012-07-30 17:25:22 -07:00
memweight.c string: introduce memweight() 2012-07-30 17:25:16 -07:00
net_utils.c mac_pton: Use bool not int return 2014-06-25 17:45:43 -07:00
nlattr.c Merge branch 'next' (accumulated 3.16 merge window patches) into master 2014-06-08 11:31:16 -07:00
notifier-error-inject.c mode_t, whack-a-mole at 11... 2013-04-09 14:13:05 -04:00
notifier-error-inject.h fault-injection: notifier error injection 2012-07-30 17:25:22 -07:00
of-reconfig-notifier-error-inject.c powerpc+of: Rename and fix OF reconfig notifier error inject module 2012-12-14 10:32:52 +11:00
oid_registry.c Give the OID registry file module info to avoid kernel tainting 2013-05-05 14:38:00 -07:00
parser.c lib/parser.c: put EXPORT_SYMBOLs in the conventional place 2014-01-23 16:36:55 -08:00
pci_iomap.c lib: add NO_GENERIC_PCI_IOPORT_MAP 2012-01-31 23:19:47 +02:00
percpu-refcount.c percpu_ref: make INIT_ATOMIC and switch_to_atomic() sticky 2014-09-24 13:31:50 -04:00
percpu_counter.c percpu_counter: add @gfp to percpu_counter_init() 2014-09-08 09:51:29 +09:00
percpu_ida.c Merge branch 'for-linus' of git://git.kernel.dk/linux-block 2014-02-14 10:45:18 -08:00
percpu_test.c percpu: add test module for various percpu operations 2013-11-13 12:09:11 +09:00
plist.c lib/plist.c: replace pr_debug with printk in plist_test() 2014-06-04 16:54:18 -07:00
pm-notifier-error-inject.c PM: PM notifier error injection module 2012-07-30 17:25:22 -07:00
proportions.c proportions: add @gfp to init functions 2014-09-08 09:51:30 +09:00
radix-tree.c radix-tree: fix race in gang lookup 2016-02-15 15:42:38 -05:00
random32.c random32: improvements to prandom_bytes 2014-08-24 18:36:01 -07:00
ratelimit.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
rational.c lib: Change mail address of Oskar Schirmer 2012-05-17 15:18:37 +02:00
rbtree.c lib/rbtree.c: fix typo in comment of __rb_insert() 2014-08-08 15:57:24 -07:00
rbtree_test.c rbtree/test: test rbtree_postorder_for_each_entry_safe() 2014-01-23 16:37:03 -08:00
reciprocal_div.c reciprocal_divide: update/correction of the algorithm 2014-01-21 23:17:20 -08:00
rhashtable.c lib/rhashtable: fix race between rhashtable_lookup_compare and hashtable resize 2015-07-01 15:33:16 -04:00
scatterlist.c lib/scatterlist: fix memory leak with scsi-mq 2014-10-28 10:27:10 -06:00
sha1.c lib: reduce the use of module.h wherever possible 2012-03-07 15:04:04 -05:00
show_mem.c mm: do not overwrite reserved pages counter at show_mem() 2014-12-02 17:32:07 -08:00
smp_processor_id.c percpu: add preemption checks to __this_cpu ops 2014-04-07 16:36:14 -07:00
sort.c generic swap(): lib/sort.c: rename swap to swap_func 2009-01-08 08:31:14 -08:00
stmp_device.c lib: add support for stmp-style devices 2012-04-20 23:27:08 +02:00
string.c lib: memzero_explicit: use barrier instead of OPTIMIZER_HIDE_VAR 2015-05-17 19:12:27 -04:00
string_helpers.c lib / string_helpers: introduce string_escape_mem() 2014-10-14 02:18:26 +02:00
strncpy_from_user.c word-at-a-time: make the interfaces truly generic 2012-05-26 11:33:40 -07:00
strnlen_user.c lib: Fix strnlen_user() to not touch memory after specified maximum 2015-06-09 14:31:43 -04:00
swiotlb.c swiotlb: don't assume PA 0 is invalid 2014-06-20 16:04:32 -04:00
syscall.c lib/syscall.c: unexport task_current_syscall() 2014-04-03 16:21:06 -07:00
test-kstrtox.c lib/test-kstrtox.c: use ARRAY_SIZE instead of sizeof/sizeof[0] 2014-08-06 18:01:25 -07:00
test-string_helpers.c lib / string_helpers: introduce string_escape_mem() 2014-10-14 02:18:26 +02:00
test_bpf.c net: bpf: fix compiler warnings in test_bpf 2014-09-22 16:21:30 -04:00
test_firmware.c test: add firmware_class loader test 2014-07-17 18:44:19 -07:00
test_module.c test: add minimal module for verification testing 2014-01-23 16:36:57 -08:00
test_user_copy.c test: check copy_to/from_user boundary validation 2014-01-23 16:36:57 -08:00
textsearch.c lib/textsearch.c: remove textsearch_put reference from comments 2014-10-14 02:18:14 +02:00
timerqueue.c The following text was taken from the original review request: 2012-03-24 10:24:31 -07:00
ts_bm.c textsearch: ts_bm: support case insensitive searching in Boyer-Moore algorithm 2008-07-08 02:37:54 -07:00
ts_fsm.c textsearch: ts_fsm: return error on request for case insensitive search 2008-07-08 02:38:27 -07:00
ts_kmp.c textsearch: ts_kmp: support case insensitive searching in Knuth-Morris-Pratt algorithm 2008-07-08 02:38:09 -07:00
ucs2_string.c Move utf16 functions to kernel core and rename 2013-04-15 21:23:03 +01:00
usercopy.c Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 2013-04-30 17:04:09 -07:00
uuid.c uuid: use prandom_bytes() 2013-04-29 18:28:42 -07:00
vsprintf.c lib/vsprintf: add %*pE[achnops] format specifier 2014-10-14 02:18:26 +02:00