linux/lib
Pablo Neira Ayuso ff491a7334 netlink: change return-value logic of netlink_broadcast()
Currently, netlink_broadcast() reports errors to the caller if no
messages at all were delivered:

1) If, at least, one message has been delivered correctly, returns 0.
2) Otherwise, if no messages at all were delivered due to skb_clone()
   failure, return -ENOBUFS.
3) Otherwise, if there are no listeners, return -ESRCH.

With this patch, the caller knows if the delivery of any of the
messages to the listeners have failed:

1) If it fails to deliver any message (for whatever reason), return
   -ENOBUFS.
2) Otherwise, if all messages were delivered OK, returns 0.
3) Otherwise, if no listeners, return -ESRCH.

In the current ctnetlink code and in Netfilter in general, we can add
reliable logging and connection tracking event delivery by dropping the
packets whose events were not successfully delivered over Netlink. Of
course, this option would be settable via /proc as this approach reduces
performance (in terms of filtered connections per seconds by a stateful
firewall) but providing reliable logging and event delivery (for
conntrackd) in return.

This patch also changes some clients of netlink_broadcast() that
may report ENOBUFS errors via printk. This error handling is not
of any help. Instead, the userspace daemons that are listening to
those netlink messages should resync themselves with the kernel-side
if they hit ENOBUFS.

BTW, netlink_broadcast() clients include those that call
cn_netlink_send(), nlmsg_multicast() and genlmsg_multicast() since they
internally call netlink_broadcast() and return its error value.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-05 23:56:36 -08:00
..
lzo lzo: use get/put_unaligned_* helpers 2008-07-25 10:53:26 -07:00
reed_solomon
zlib_deflate
zlib_inflate
.gitignore
argv_split.c
audit.c
bcd.c rtc: BCD codeshrink 2008-07-24 10:47:33 -07:00
bitmap.c Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/dvrabel/uwb 2008-10-23 08:20:34 -07:00
bitrev.c
bug.c allow bug table entries to use relative pointers (and use it on x86-64) 2008-12-16 18:40:32 +01:00
bust_spinlocks.c oops handling: ensure that any oops is flushed to the mtdoops console 2009-01-06 15:59:11 -08:00
check_signature.c
cmdline.c generic, memparse(): constify argument 2008-07-28 15:05:23 +02:00
cpumask.c cpumask: zero extra bits in alloc_cpumask_var_node 2009-01-01 10:12:30 +10:30
crc7.c
crc16.c
crc32.c
crc32defs.h
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c [SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC 2008-07-12 08:22:32 -05:00
ctype.c
debug_locks.c debug_locks: set oops_in_progress if we will log messages. 2008-08-01 10:46:43 +02:00
debugobjects.c debugobjects: add boot parameter default value 2008-11-26 10:07:06 +01:00
dec_and_lock.c
devres.c
div64.c
dump_stack.c
dynamic_printk.c dynamic_printk: reduce one level of indentation 2009-01-06 10:44:32 -08:00
extable.c
fault-inject.c Remove remaining unwinder code 2009-01-06 15:59:11 -08:00
find_last_bit.c bitmap: find_last_bit() 2009-01-01 10:12:19 +10:30
find_next_bit.c
gen_crc32table.c
genalloc.c
halfmd4.c
hexdump.c
hweight.c
idr.c lib/idr.c: use kmem_cache_zalloc() for the idr_layer cache 2009-01-15 16:39:40 -08:00
inflate.c inflate: refactor inflate malloc code 2008-07-25 10:53:28 -07:00
int_sqrt.c
iomap_copy.c
iomap.c Use WARN() in lib/ 2008-07-26 12:00:07 -07:00
iommu-helper.c introduce generic iommu_num_pages function 2008-10-16 11:21:33 -07:00
ioremap.c
irq_regs.c
is_single_threaded.c CRED: Rename is_single_threaded() to is_wq_single_threaded() 2008-11-14 10:39:21 +11:00
kasprintf.c
Kconfig Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-02 11:44:09 -08:00
Kconfig.debug Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-26 09:47:56 -08:00
Kconfig.kgdb kgdb: remove the requirement for CONFIG_FRAME_POINTER 2008-08-01 08:39:34 -05:00
kernel_lock.c
klist.c driver core: Remove completion from struct klist_node 2009-01-06 10:44:30 -08:00
kobject_uevent.c netlink: change return-value logic of netlink_broadcast() 2009-02-05 23:56:36 -08:00
kobject.c kobject: Cleanup kobject_rename and !CONFIG_SYSFS 2008-10-16 09:24:52 -07:00
kref.c
libcrc32c.c libcrc32c: Fix "crc32c undefined" compilation error 2008-12-25 11:01:42 +11:00
list_debug.c list debugging: use WARN() instead of BUG() 2008-07-25 10:53:29 -07:00
lmb.c lmb: Fix reserved region handling in lmb_enforce_memory_limit(). 2008-08-15 19:57:57 -07:00
locking-selftest-hardirq.h
locking-selftest-mutex.h
locking-selftest-rlock-hardirq.h
locking-selftest-rlock-softirq.h
locking-selftest-rlock.h
locking-selftest-rsem.h
locking-selftest-softirq.h
locking-selftest-spin-hardirq.h
locking-selftest-spin-softirq.h
locking-selftest-spin.h
locking-selftest-wlock-hardirq.h
locking-selftest-wlock-softirq.h
locking-selftest-wlock.h
locking-selftest-wsem.h
locking-selftest.c
Makefile bitmap: find_last_bit() 2009-01-01 10:12:19 +10:30
parser.c vfs: Use const for kernel parser table 2008-10-13 10:10:37 -07:00
percpu_counter.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-06 17:10:04 -08:00
plist.c Use WARN() in lib/ 2008-07-26 12:00:07 -07:00
prio_heap.c lib: fix sparse shadowed variable warning 2009-01-06 15:59:11 -08:00
prio_tree.c
proportions.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-06 17:10:04 -08:00
radix-tree.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2009-01-07 11:31:52 -08:00
random32.c random32: seeding improvement 2008-07-30 16:29:19 -07:00
ratelimit.c __ratelimit() cpu flags can't be static 2008-07-28 16:30:20 -07:00
rbtree.c rbtree: add const qualifier to some functions 2009-01-10 06:04:33 -08:00
reciprocal_div.c
rwsem-spinlock.c
rwsem.c
scatterlist.c lib/scatterlist.c: fix kunmap() argument in sg_miter_stop() 2008-11-19 18:49:58 -08:00
sha1.c
show_mem.c lib: generic show_mem() 2008-07-26 12:00:10 -07:00
smp_processor_id.c cpumask: convert lib/smp_processor_id to new cpumask ops 2009-01-30 15:47:34 +01:00
sort.c generic swap(): lib/sort.c: rename swap to swap_func 2009-01-08 08:31:14 -08:00
spinlock_debug.c
string_helpers.c [SCSI] lib: string_get_size(): don't hang on zero; no decimals on exact 2008-10-23 11:42:20 -05:00
string.c
swiotlb.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-06 17:10:04 -08:00
syscall.c task_current_syscall 2008-07-26 12:00:10 -07:00
textsearch.c remove CONFIG_KMOD from lib 2008-07-22 19:24:31 +10:00
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
vsprintf.c strict_strto* is not strict enough 2009-01-06 15:59:12 -08:00