linux/include, branch v3.4.26

libceph: remove 'osdtimeout' option

2013-01-17T16:51:20Z

This would reset a connection with any OSD that had an outstanding request that was taking more than N seconds. The idea was that if the OSD was buggy, the client could compensate by resending the request. In reality, this only served to hide server bugs, and we haven't actually seen such a bug in quite a while. Moreover, the userspace client code never did this. More importantly, often the request is taking a long time because the OSD is trying to recover, or overloaded, and killing the connection and retrying would only make the situation worse by giving the OSD more work to do. Signed-off-by: Sage Weil Reviewed-by: Alex Elder (cherry picked from commit 83aff95eb9d60aff5497e9f44a2ae906b86d8e88) Signed-off-by: Greg Kroah-Hartman

mm: limit mmu_gather batching to fix soft lockups on !CONFIG_PREEMPT

2013-01-11T17:07:18Z

commit 53a59fc67f97374758e63a9c785891ec62324c81 upstream. Since commit e303297e6c3a ("mm: extended batches for generic mmu_gather") we are batching pages to be freed until either tlb_next_batch cannot allocate a new batch or we are done. This works just fine most of the time but we can get in troubles with non-preemptible kernel (CONFIG_PREEMPT_NONE or CONFIG_PREEMPT_VOLUNTARY) on large machines where too aggressive batching might lead to soft lockups during process exit path (exit_mmap) because there are no scheduling points down the free_pages_and_swap_cache path and so the freeing can take long enough to trigger the soft lockup. The lockup is harmless except when the system is setup to panic on softlockup which is not that unusual. The simplest way to work around this issue is to limit the maximum number of batches in a single mmu_gather. 10k of collected pages should be safe to prevent from soft lockups (we would have 2ms for one) even if they are all freed without an explicit scheduling point. This patch doesn't add any new explicit scheduling points because it relies on zap_pmd_range during page tables zapping which calls cond_resched per PMD. The following lockup has been reported for 3.0 kernel with a huge process (in order of hundreds gigs but I do know any more details). BUG: soft lockup - CPU#56 stuck for 22s! [kernel:31053] Modules linked in: af_packet nfs lockd fscache auth_rpcgss nfs_acl sunrpc mptctl mptbase autofs4 binfmt_misc dm_round_robin dm_multipath bonding cpufreq_conservative cpufreq_userspace cpufreq_powersave pcc_cpufreq mperf microcode fuse loop osst sg sd_mod crc_t10dif st qla2xxx scsi_transport_fc scsi_tgt netxen_nic i7core_edac iTCO_wdt joydev e1000e serio_raw pcspkr edac_core iTCO_vendor_support acpi_power_meter rtc_cmos hpwdt hpilo button container usbhid hid dm_mirror dm_region_hash dm_log linear uhci_hcd ehci_hcd usbcore usb_common scsi_dh_emc scsi_dh_alua scsi_dh_hp_sw scsi_dh_rdac scsi_dh dm_snapshot pcnet32 mii edd dm_mod raid1 ext3 mbcache jbd fan thermal processor thermal_sys hwmon cciss scsi_mod Supported: Yes CPU 56 Pid: 31053, comm: kernel Not tainted 3.0.31-0.9-default #1 HP ProLiant DL580 G7 RIP: 0010: _raw_spin_unlock_irqrestore+0x8/0x10 RSP: 0018:ffff883ec1037af0 EFLAGS: 00000206 RAX: 0000000000000e00 RBX: ffffea01a0817e28 RCX: ffff88803ffd9e80 RDX: 0000000000000200 RSI: 0000000000000206 RDI: 0000000000000206 RBP: 0000000000000002 R08: 0000000000000001 R09: ffff887ec724a400 R10: 0000000000000000 R11: dead000000200200 R12: ffffffff8144c26e R13: 0000000000000030 R14: 0000000000000297 R15: 000000000000000e FS: 00007ed834282700(0000) GS:ffff88c03f200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 000000000068b240 CR3: 0000003ec13c5000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process kernel (pid: 31053, threadinfo ffff883ec1036000, task ffff883ebd5d4100) Call Trace: release_pages+0xc5/0x260 free_pages_and_swap_cache+0x9d/0xc0 tlb_flush_mmu+0x5c/0x80 tlb_finish_mmu+0xe/0x50 exit_mmap+0xbd/0x120 mmput+0x49/0x120 exit_mm+0x122/0x160 do_exit+0x17a/0x430 do_group_exit+0x3d/0xb0 get_signal_to_deliver+0x247/0x480 do_signal+0x71/0x1b0 do_notify_resume+0x98/0xb0 int_signal+0x12/0x17 DWARF2 unwinder stuck at int_signal+0x12/0x17 Signed-off-by: Michal Hocko Cc: Mel Gorman Cc: Rik van Riel Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

PCI: Reduce Ricoh 0xe822 SD card reader base clock frequency to 50MHz

2013-01-11T17:07:16Z

commit 812089e01b9f65f90fc8fc670d8cce72a0e01fbb upstream. Otherwise it fails like this on cards like the Transcend 16GB SDHC card: mmc0: new SDHC card at address b368 mmcblk0: mmc0:b368 SDC 15.0 GiB mmcblk0: error -110 sending status command, retrying mmcblk0: error -84 transferring data, sector 0, nr 8, cmd response 0x900, card status 0xb0 Tested on my Lenovo x200 laptop. [bhelgaas: changelog] Signed-off-by: Andy Lutomirski Signed-off-by: Bjorn Helgaas Acked-by: Chris Ball CC: Manoj Iyer Signed-off-by: Greg Kroah-Hartman

tcp: implement RFC 5961 4.2

2013-01-11T17:07:15Z

[ Upstream commit 0c24604b68fc7810d429d6c3657b6f148270e528 ] Implement the RFC 5691 mitigation against Blind Reset attack using SYN bit. Section 4.2 of RFC 5961 advises to send a Challenge ACK and drop incoming packet, instead of resetting the session. Add a new SNMP counter to count number of challenge acks sent in response to SYN packets. (netstat -s | grep TCPSYNChallenge) Remove obsolete TCPAbortOnSyn, since we no longer abort a TCP session because of a SYN flag. Signed-off-by: Eric Dumazet Cc: Kiran Kumar Kella Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: implement RFC 5961 3.2

2013-01-11T17:07:14Z

[ Upstream commit 282f23c6ee343126156dd41218b22ece96d747e3 ] Implement the RFC 5691 mitigation against Blind Reset attack using RST bit. Idea is to validate incoming RST sequence, to match RCV.NXT value, instead of previouly accepted window : (RCV.NXT <= SEG.SEQ < RCV.NXT+RCV.WND) If sequence is in window but not an exact match, send a "challenge ACK", so that the other part can resend an RST with the appropriate sequence. Add a new sysctl, tcp_challenge_ack_limit, to limit number of challenge ACK sent per second. Add a new SNMP counter to count number of challenge acks sent. (netstat -s | grep TCPChallengeACK) Signed-off-by: Eric Dumazet Cc: Kiran Kumar Kella Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

inet: Fix kmemleak in tcp_v4/6_syn_recv_sock and dccp_v4/6_request_recv_sock

2013-01-11T17:07:14Z

[ Upstream commit e337e24d6624e74a558aa69071e112a65f7b5758 ] If in either of the above functions inet_csk_route_child_sock() or __inet_inherit_port() fails, the newsk will not be freed: unreferenced object 0xffff88022e8a92c0 (size 1592): comm "softirq", pid 0, jiffies 4294946244 (age 726.160s) hex dump (first 32 bytes): 0a 01 01 01 0a 01 01 02 00 00 00 00 a7 cc 16 00 ................ 02 00 03 01 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmemleak_alloc+0x21/0x3e [] kmem_cache_alloc+0xb5/0xc5 [] sk_prot_alloc.isra.53+0x2b/0xcd [] sk_clone_lock+0x16/0x21e [] inet_csk_clone_lock+0x10/0x7b [] tcp_create_openreq_child+0x21/0x481 [] tcp_v4_syn_recv_sock+0x3a/0x23b [] tcp_check_req+0x29f/0x416 [] tcp_v4_do_rcv+0x161/0x2bc [] tcp_v4_rcv+0x6c9/0x701 [] ip_local_deliver_finish+0x70/0xc4 [] ip_local_deliver+0x4e/0x7f [] ip_rcv_finish+0x1fc/0x233 [] ip_rcv+0x217/0x267 [] __netif_receive_skb+0x49e/0x553 [] netif_receive_skb+0x50/0x82 This happens, because sk_clone_lock initializes sk_refcnt to 2, and thus a single sock_put() is not enough to free the memory. Additionally, things like xfrm, memcg, cookie_values,... may have been initialized. We have to free them properly. This is fixed by forcing a call to tcp_done(), ending up in inet_csk_destroy_sock, doing the final sock_put(). tcp_done() is necessary, because it ends up doing all the cleanup on xfrm, memcg, cookie_values, xfrm,... Before calling tcp_done, we have to set the socket to SOCK_DEAD, to force it entering inet_csk_destroy_sock. To avoid the warning in inet_csk_destroy_sock, inet_num has to be set to 0. As inet_csk_destroy_sock does a dec on orphan_count, we first have to increase it. Calling tcp_done() allows us to remove the calls to tcp_clear_xmit_timer() and tcp_cleanup_congestion_control(). A similar approach is taken for dccp by calling dccp_done(). This is in the kernel since 093d282321 (tproxy: fix hash locking issue when using port redirection in __inet_inherit_port()), thus since version >= 2.6.37. Signed-off-by: Christoph Paasch Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

freezer: add missing mb's to freezer_count() and freezer_should_skip()

2013-01-11T17:06:58Z

commit dd67d32dbc5de299d70cc9e10c6c1e29ffa56b92 upstream. A task is considered frozen enough between freezer_do_not_count() and freezer_count() and freezers use freezer_should_skip() to test this condition. This supposedly works because freezer_count() always calls try_to_freezer() after clearing %PF_FREEZER_SKIP. However, there currently is nothing which guarantees that freezer_count() sees %true freezing() after clearing %PF_FREEZER_SKIP when freezing is in progress, and vice-versa. A task can escape the freezing condition in effect by freezer_count() seeing !freezing() and freezer_should_skip() seeing %PF_FREEZER_SKIP. This patch adds smp_mb()'s to freezer_count() and freezer_should_skip() such that either %true freezing() is visible to freezer_count() or !PF_FREEZER_SKIP is visible to freezer_should_skip(). Signed-off-by: Tejun Heo Cc: Oleg Nesterov Cc: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

mm: Fix PageHead when !CONFIG_PAGEFLAGS_EXTENDED

2013-01-11T17:06:48Z

commit ad4b3fb7ff9940bcdb1e4cd62bd189d10fa636ba upstream. Unfortunately with !CONFIG_PAGEFLAGS_EXTENDED, (!PageHead) is false, and (PageHead) is true, for tail pages. If this is indeed the intended behavior, which I doubt because it breaks cache cleaning on some ARM systems, then the nomenclature is highly problematic. This patch makes sure PageHead is only true for head pages and PageTail is only true for tail pages, and neither is true for non-compound pages. [ This buglet seems ancient - seems to have been introduced back in Apr 2008 in commit 6a1e7f777f61: "pageflags: convert to the use of new macros". And the reason nobody noticed is because the PageHead() tests are almost all about just sanity-checking, and only used on pages that are actual page heads. The fact that the old code returned true for tail pages too was thus not really noticeable. - Linus ] Signed-off-by: Christoffer Dall Acked-by: Andrea Arcangeli Cc: Andrew Morton Cc: Will Deacon Cc: Steve Capper Cc: Christoph Lameter Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

exec: do not leave bprm->interp on stack

2013-01-11T17:06:30Z

commit b66c5984017533316fd1951770302649baf1aa33 upstream. If a series of scripts are executed, each triggering module loading via unprintable bytes in the script header, kernel stack contents can leak into the command line. Normally execution of binfmt_script and binfmt_misc happens recursively. However, when modules are enabled, and unprintable bytes exist in the bprm->buf, execution will restart after attempting to load matching binfmt modules. Unfortunately, the logic in binfmt_script and binfmt_misc does not expect to get restarted. They leave bprm->interp pointing to their local stack. This means on restart bprm->interp is left pointing into unused stack memory which can then be copied into the userspace argv areas. After additional study, it seems that both recursion and restart remains the desirable way to handle exec with scripts, misc, and modules. As such, we need to protect the changes to interp. This changes the logic to require allocation for any changes to the bprm->interp. To avoid adding a new kmalloc to every exec, the default value is left as-is. Only when passing through binfmt_script or binfmt_misc does an allocation take place. For a proof of concept, see DoTest.sh from: http://www.halfdog.net/Security/2012/LinuxKernelBinfmtScriptStackDataDisclosure/ Signed-off-by: Kees Cook Cc: halfdog Cc: P J P Cc: Alexander Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

tmpfs: fix shared mempolicy leak

2012-12-17T18:37:42Z

commit 18a2f371f5edf41810f6469cb9be39931ef9deb9 upstream. This fixes a regression in 3.7-rc, which has since gone into stable. Commit 00442ad04a5e ("mempolicy: fix a memory corruption by refcount imbalance in alloc_pages_vma()") changed get_vma_policy() to raise the refcount on a shmem shared mempolicy; whereas shmem_alloc_page() went on expecting alloc_page_vma() to drop the refcount it had acquired. This deserves a rework: but for now fix the leak in shmem_alloc_page(). Hugh: shmem_swapin() did not need a fix, but surely it's clearer to use the same refcounting there as in shmem_alloc_page(), delete its onstack mempolicy, and the strange mpol_cond_copy() and __mpol_cond_copy() - those were invented to let swapin_readahead() make an unknown number of calls to alloc_pages_vma() with one mempolicy; but since 00442ad04a5e, alloc_pages_vma() has kept refcount in balance, so now no problem. Reported-and-tested-by: Tommi Rantala Signed-off-by: Mel Gorman Signed-off-by: Hugh Dickins Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman