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2016-09-15all pools have their ipl set via pool_setipl, so fold it into pool_init.David Gwynne
the ioff argument to pool_init() is unused and has been for many years, so this replaces it with an ipl argument. because the ipl will be set on init we no longer need pool_setipl. most of these changes have been done with coccinelle using the spatch below. cocci sucks at formatting code though, so i fixed that by hand. the manpage and subr_pool.c bits i did myself. ok tedu@ jmatthew@ @ipl@ expression pp; expression ipl; expression s, a, o, f, m, p; @@ -pool_init(pp, s, a, o, f, m, p); -pool_setipl(pp, ipl); +pool_init(pp, s, a, ipl, f, m, p);
2016-09-03Only use uaddr_exe for address selection when PROT_EXEC is requestedStefan Kempf
Checking whether a memory range could be mprotect()'ed to PROT_EXEC attempts to put every mapping into the uaddr_exe range, if it exists. This would fill up the exe range on i386 quickly, once uaddr_exe gets used. So only use uaddr_exe if we know PROT_EXEC is needed for sure No change in current behavior, since uaddr_exe will only be used with uvm pivots. ok tedu@
2016-09-02Mask out lower bits of randomly selected addressStefan Kempf
Fixes uvm pivots bug that would create non-page aligned addresses. This fix is in code that's not yet enabled.
2016-08-31Simplify arguments to uaddr_*_create functionsStefan Kempf
min is already clamped before invoking these functions. ok kettenis@
2016-08-18uvm_wxcheck() should only abort the process if kern.wxabort is set.Theo de Raadt
The new semantics are W^X violations are reported to the application via ENOTSUP. Forgot to fix this during the last change. Spotted by kettenis
2016-08-12Include map entries that have an amap associated with them in the coredump.Mark Kettenis
This fixes coredumps of processes that use relro to make part of their writable address space read-only. ok guenther@
2016-08-11replace abuse of the static map entries RB_ENTRY pointers with an SLISTDavid Gwynne
free static entries are kept in a simple linked list, so use SLIST to make this obvious. the RB_PARENT manipulations are ugly and confusing. ok kettenis@
2016-08-08W^X violations are only permitted for binaries marked "wxneeded" onTheo de Raadt
"wxallowed" filesystems. mmap(2) & mprotect(2) now return ENOTSUP. (To diagnose buggy programs, consider using sysctl kern.wxabort=1 and looking at the coredumps) ok kettenis tedu naddy
2016-07-30Check for wraparound before the "commit" phase of uvm_map() and uvm_mapanon(),Mark Kettenis
to prevent hitting assertions and/or corrupting data structures during that phase. ok deraadt@, tedu@
2016-07-30Add a few checks for potential integer overflow and underflow related to theMark Kettenis
size of an address range. ok deraadt@, tedu@
2016-07-29add a check that the arguments to isavail don't overflow.Ted Unangst
callers should probably check too, but checking here won't hurt. possible panic reported by tim newsham. ok kettenis
2016-07-27check flags with mask instead of equality, in case we decide to mixTed Unangst
another flag in at some point. ok stefan
2016-07-14Make sure that amap slot calculation does not overflowStefan Kempf
This prevents from too small amaps being allocated by forcing the allocation of a large number of slots. Based on an analysis from Jesse Hertz and Tim Newsham. ok kettenis@
2016-07-13Since mappings established using __MAP_NOFAULT will be converted into anonymousMark Kettenis
memory if the file backing the mapping is truncated, we should check resource limits. This prevents callers from triggering a kernel panic and a potential integer overflow in the amap code by forcing the allocation of too many slots. Based on an analysis from Jesse Hertz and Tim Newsham. ok deraadt@
2016-07-13Revert previous; the __MAP_NOFAULT test is inverted and the commit message isMark Kettenis
wrong.
2016-07-13Since mappings established using __MAP_NOFAIL will be converted into anonymousMark Kettenis
memory if the file backing the mapping is truncated, we should check resource limits. This prevents callers from triggering a kernel panic and a potential integer overflow in the amap code by forcing the allocation of too many slots. Based on an analysis from Jesse Hertz and Tim Newsham. ok deraadt@
2016-07-11Make sure variables are used initialized in amap_wiperangeStefan Kempf
Uninitialized variables used in an if/else could cause a slower codepath to be taken, but the end effect of both paths is the same. Found by jsg@
2016-07-09Fix bugs introduced with the amap reworkStefan Kempf
- The number of slots must be initialized in the chunk of a small amap, otherwise unmapping() part of a mmap()'d range would delay freeing of vm_anons for small amaps - If the first chunk of a bucket is freed, check if the next chunk in the list has to become the new first chunk - Use a separate loop for each type of traversal (small amap, by bucket by list) in amap_wiperange(). This makes the code easier to follow and also fixes a bug where too many chunks were wiped out when traversing by list However, the last two bugs should happen only when turning a previously private mapping into a shared one, then forking, and then having both processes unmap a part of the mapping. snap and ports build tested by krw@, review by kettenis@
2016-06-17pool_setipl on all uvm pools.David Gwynne
ok kettenis@ visa@
2016-06-13In uvm_map(), call uvm_unmap_detach_intrsafe() if we have an interrupt-safeMark Kettenis
map, to avoid grabbing the kernel lock when pool_get() needs to allocate a new pool page. Hopefully this really is the last case where we might grab the kernel lock for interrupt-safe pools. ok mpi@
2016-06-08Dereference p_p once rather than 4 times.Theo de Raadt
2016-06-08hppa & mips64 now can do the full W^X check. (Make sure you haveTheo de Raadt
a new kernel before this change, and ld.so updated)
2016-06-05Add uvm_share() to share a memory range between two address spacesStefan Kempf
Its primary use is to make guest VM memory accessible to the host (e.g. vmd(8)). That will later allow us to remove the readpage and writepage ioctls from vmm(4), and use ordinary loads and stores instead. "looks good to me" kettenis@
2016-06-04If a process trips the W^X violation check, abort it unless it cameStuart Henderson
from a filesystem with the wxallowed flag set. ok deraadt Current status: Filesystem Binary Action ---------- ------ ------ wxallowed normal violation -> log but don't abort wxallowed wxneeded W^X silently allowed normal normal violation -> abort normal wxneeded process won't run at all See http://www.openbsd.org/faq/current.html#r20160527
2016-06-03We should never decrease uvm_maxkaddr. Currently this may happen ifMark Kettenis
uvm_map_kmem_grow() gets called for submaps of the kernel_map on architectures that don't implement pmap_growkernel(). When that happens we get the infamous "address selector returned unavailable address" panic. ok tedu@, mglocker@, beck@, stefan@
2016-06-02print the size when an unavailable address is returned. it is useful.Ted Unangst
ok millert stefan
2016-06-02Prevent vsize_t underflow when checking RLIMIT_DATA, which made theIngo Schwarze
check ineffective when you already had more memory than your limit allowed. I noticed after writing this diff that millert@ already committed a fix for this in rev. 1.74 (2009/06/01), but it got backed out with the giant pmemrange backout two weeks later and was never restored. OK tedu@ ("just fix it" and "go ahead with your version") stefan@ also agrees that a check is needed.
2016-06-01Delete the kernel compat bits for old mmap() MAP_OLD* flagsPhilip Guenther
ok deraadt@ matthew@ jca@
2016-05-30Identify W^X labelled binaries at execve() time based upon WX_OPENBSD_WXNEEDEDTheo de Raadt
flag set by ld -zwxneeded. Such binaries are allowed to run only on wxallowed mountpoints. They do not report mmap/mprotect problems. Rate limit mmap/mprotect reports from other binaries. These semantics are chosen to encourage progress in the ports ecosystem, without overwhelming the developers who work in the area. ok sthen kettenis
2016-05-30backout to insert correct commit messageTheo de Raadt
2016-05-30*** empty log message ***Theo de Raadt
2016-05-27W^X violations are no longer permitted by default. A kernel log messageTheo de Raadt
is generated, and mprotect/mmap return ENOTSUP. If the sysctl(8) flag kern.wxabort is set then a SIGABRT occurs instead, for gdb use or coredump creation. W^X violating programs can be permitted on a ffs/nfs filesystem-basis, using the "wxallowed" mount option. One day far in the future upstream software developers will understand that W^X violations are a tremendously risky practice and that style of programming will be banished outright. Until then, we recommend most users need to use the wxallowed option on their /usr/local filesystem. At least your other filesystems don't permit such programs. ok jca kettenis mlarkin natano
2016-05-26Make amaps use less kernel memory (2nd try)Stefan Kempf
The original diff would crash at least i386 and powerpc, as spotted by guenther@ The reason was an incorrect use of sizeof in amap_lookups(). Confirmation that powerpc works by mpi@ and mglocker@ "throw it in" deraadt@ Original commit message: This is achieved by grouping amap slots into chunks that are allocated on-demand by pool(9). Endless "fltamapcopy" loops because of kmem shortage should be solved now. The kmem savings are also important to later enable vmm(4) to use larged shared memory mappings for guest VM RAM. This adapts libkvm also because the amap structure layout has changed. Testing and fix of libkvm glitch in initial diff by tb@ Feedback and "time to get this in" kettenis@
2016-05-22Revert previous: breaks i386 and powerpc, probably all non-PMAP_DIRECT archsPhilip Guenther
2016-05-22Make amaps use less kernel memoryStefan Kempf
This is achieved by grouping amap slots into chunks that are allocated on-demand by pool(9). Endless "fltamapcopy" loops because of kmem shortage should be solved now. The kmem savings are also important to later enable vmm(4) to use larged shared memory mappings for guest VM RAM. This adapts libkvm also because the amap structure layout has changed. Testing and fix of libkvm glitch in initial diff by tb@ Feedback and "time to get this in" kettenis@
2016-05-11remove hppa64 port, which we never got going beyond broken single users.Theo de Raadt
hppa reverse-stack gives us a valuable test case, but most developers don't have a 2nd one to proceed further with this. ok kettenis
2016-05-08Additional parameter for amap_alloc().Stefan Kempf
It is supposed to control whether an amap should allocate memory to store anon pointers lazily or upfront. Needed for upcoming amap changes. ok kettenis@
2016-05-08Wait for RAM in uvm_fault when allocating uvm structures failsStefan Kempf
Only fail hard when running out of swap space also, as suggested by kettenis@ While there, let amap_add() return a success status and handle amap_add() errors in uvm_fault() similar to other out of RAM situations. These bits are needed for further amap reorganization diffs. lots of feedback and ok kettenis@
2016-05-05Remove uvm_mapentry_freecmp which has been unused for yearsStefan Kempf
Found by David Hill with clang.
2016-04-16Remove am_maxslot from amap.Stefan Kempf
am_maxslot represents the total number of slots an amap can be extended to. Since we do not extend amaps, this field as well as rounding the number of slots to the next malloc bucket is not useful. This also removes the corresponding output from procmap(1). ok kettenis@
2016-04-12Simplify amap traversal in amap_swap_off.Stefan Kempf
There's no need to insert marker elements to find the next item in the amap list. The next amap can be determined by looking at the currently examined amap. Care must be taken to get the next element before the current amap is possibly deleted, and after all the current amap's pages were read in from swap (because the page-in may sleep and remove items from the amap list).
2016-04-04UVM_FLAG_AMAPPAD has no effect anymore, nuke it.Stefan Kempf
This flag caused amaps to be allocated with additional spare slots, to make extending them cheaper. However, the kernel never extends amaps, so allocating spare slots is pointless. Also UVM_FLAG_AMAPPAD only has an effect in combination with UVM_FLAG_OVERLAY. The only function that used both flags was sys_obreak, but that function had the use of UVM_FLAG_OVERLAY removed recently. While there, kill the unused prototypes amap_flags and amap_refs. They're defined as macros already. ok mlarkin@ kettenis@ mpi@
2016-03-29Remove dead assignments and now unused variables.Charles Longeau
Found by LLVM/Clang Static Analyzer. ok mpi@ stefan@
2016-03-27amap_extend is never called, remove it.Stefan Kempf
In the code, this function is called when vm_map_entries are merged. However, only kernel map entries are merged, and these do not use amaps. Therefore amap_extend() is never called at runtime. ok millert@, KASSERT suggestion and ok mpi@
2016-03-19Remove the unused flags argument from VOP_UNLOCK().natano
torture tested on amd64, i386 and macppc ok beck mpi stefan "the change looks right" deraadt
2016-03-16Remove redundant check.Stefan Kempf
The compiler is also smart enough to recognize that this is redundant. The resulting code on amd64 is basically equivalent (slightly different register allocation and instruction scheduling). ok mpi@ deraadt@
2016-03-15'accomodate' -> 'accommodate' in comments.Kenneth R Westerback
Started by diff from Mical Mazurek.
2016-03-15Allocate amap slots for a virtual memory range reserved with sbrk lazily.Stefan Kempf
This avoids wasting kernel memory if the user process does not make use of the allocated memory. Testing by sthen@ and tobiasu@, thanks! ok deraadt@
2016-03-15For amaps with only a few slots, allocate the slots via pool(9)Stefan Kempf
This saves some memory compared to using malloc, because there's no roundup to the next bucket size. And it reduces kmem pressure at least for some architectures (e.g. amd64). Testing by sthen@ and tobiasu@, thanks! ok sthen@ deraadt@
2016-03-09remove vaxismsTheo de Raadt