Nick Piggin 124d3b7041 fix writev regression: pan hanging unkillable and un-straceable ... Frederik Himpe reported an unkillable and un-straceable pan process. Zero length iovecs can go into an infinite loop in writev, because the iovec iterator does not always advance over them. The sequence required to trigger this is not trivial. I think it requires that a zero-length iovec be followed by a non-zero-length iovec which causes a pagefault in the atomic usercopy. This causes the writev code to drop back into single-segment copy mode, which then tries to copy the 0 bytes of the zero-length iovec; a zero length copy looks like a failure though, so it loops. Put a test into iov_iter_advance to catch zero-length iovecs. We could just put the test in the fallback path, but I feel it is more robust to skip over zero-length iovecs throughout the code (iovec iterator may be used in filesystems too, so it should be robust). Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2008-02-03 07:55:39 +11:00
..
allocpercpu.c	Slab allocators: Replace explicit zeroing with __GFP_ZERO	2007-07-17 10:23:02 -07:00
backing-dev.c	mm/backing-dev.c: fix percpu_counter_destroy call bug in bdi_init	2007-12-05 09:21:18 -08:00
bootmem.c
bounce.c	block: Initial support for data-less (or empty) barrier support	2007-10-16 11:03:56 +02:00
fadvise.c
filemap_xip.c	xip: fix get_zeroed_page with __GFP_HIGHMEM	2008-01-08 16:10:36 -08:00
filemap.c	fix writev regression: pan hanging unkillable and un-straceable	2008-02-03 07:55:39 +11:00
fremap.c	remap_file_pages: kernel-doc corrections	2007-10-17 08:43:07 -07:00
highmem.c	Create the ZONE_MOVABLE zone	2007-07-17 10:22:59 -07:00
hugetlb.c	fix hugepages leak due to pagetable page sharing	2008-01-24 08:07:27 -08:00
internal.h	Breakout page_order() to internal.h to avoid special knowledge of the buddy allocator	2007-10-16 09:43:01 -07:00
Kconfig	sh: Bump number of quicklists for SH-5.	2008-01-28 13:18:55 +09:00
madvise.c	speed up madvise_need_mmap_write() usage	2007-07-16 09:05:36 -07:00
Makefile	memory unplug: page isolation	2007-10-16 09:43:02 -07:00
memory_hotplug.c	Add IORESOUCE_BUSY flag for System RAM	2007-11-14 18:45:39 -08:00
memory.c	x86: print which shared library/executable faulted in segfault etc. messages v3	2008-01-30 13:33:18 +01:00
mempolicy.c	Migration: find correct vma in new_vma_page()	2007-11-14 18:45:38 -08:00
mempool.c	spelling fixes: mm/	2007-10-20 01:27:18 +02:00
migrate.c	Typo fixes retrun -> return	2007-10-20 02:13:26 +02:00
mincore.c
mlock.c	do not limit locked memory when RLIMIT_MEMLOCK is RLIM_INFINITY	2007-07-16 09:05:37 -07:00
mmap.c	x86: randomize brk	2008-01-30 13:30:40 +01:00
mmzone.c
mprotect.c	fix mprotect vma_wants_writenotify prot	2007-10-23 08:32:06 -07:00
mremap.c	sparse pointer use of zero as null	2007-10-18 14:37:31 -07:00
msync.c
nommu.c	Security: round mmap hint address above mmap_min_addr	2007-12-06 00:25:10 +11:00
oom_kill.c	sched: sched_rt_entity	2008-01-25 21:08:27 +01:00
page_alloc.c	mm: fix section mismatch warning in page_alloc.c	2008-01-17 15:38:58 -08:00
page_io.c	Drop 'size' argument from bio_endio and bi_end_io	2007-10-10 09:25:57 +02:00
page_isolation.c	memory hotremove: unset migrate type "ISOLATE" after removal	2007-11-14 18:45:38 -08:00
page-writeback.c	Revert "writeback: introduce writeback_control.more_io to indicate more io"	2008-01-14 21:21:29 -08:00
pdflush.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
prio_tree.c	spelling fixes: mm/	2007-10-20 01:27:18 +02:00
quicklist.c	quicklists: Only consider memory that can be used with GFP_KERNEL	2008-01-14 08:52:22 -08:00
readahead.c	mm: bdi init hooks	2007-10-17 08:42:45 -07:00
rmap.c	[S390] Optimize storage key handling for anonymous pages	2007-11-20 11:13:46 +01:00
shmem_acl.c
shmem.c	tmpfs: restore missing clear_highpage	2007-11-28 11:04:28 -08:00
slab.c	cpu-hotplug: replace per-subsystem mutexes with get_online_cpus()	2008-01-25 21:08:02 +01:00
slob.c	Avoid double memclear() in SLOB/SLUB	2007-12-09 10:17:52 -08:00
slub.c	Kobject: convert mm/slub.c to use kobject_init/add_ng()	2008-01-24 20:40:31 -08:00
sparse-vmemmap.c	memory hotplug fix: fix section mismatch in vmammap_allock_block()	2007-11-29 09:24:54 -08:00
sparse.c	mm/sparse.c: improve the error handling for sparse_add_one_section()	2007-12-17 19:28:16 -08:00
swap_state.c	mm: clarify __add_to_swap_cache locking	2007-10-16 09:42:53 -07:00
swap.c	spelling fixes: mm/	2007-10-20 01:27:18 +02:00
swapfile.c	Replace CONFIG_SOFTWARE_SUSPEND with CONFIG_HIBERNATION	2007-07-29 16:45:38 -07:00
thrash.c
tiny-shmem.c	r/o bind mounts: filesystem helpers for custom 'struct file's	2007-10-17 08:43:04 -07:00
truncate.c	Drop some headers from mm.h	2007-10-17 08:42:55 -07:00
util.c	fix mm/util.c:krealloc()	2007-11-14 18:45:41 -08:00
vmalloc.c	spelling fixes: mm/	2007-10-20 01:27:18 +02:00
vmscan.c	spelling fixes: mm/	2007-10-20 01:27:18 +02:00
vmstat.c	vmstat: fix section mismatch warning	2007-11-14 18:45:42 -08:00