- 07 Jan, 2011 24 commits
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Slava Pestov authored
commit 364829b1 upstream. The file_ops struct for the "trace" special file defined llseek as seq_lseek(). However, if the file was opened for writing only, seq_open() was not called, and the seek would dereference a null pointer, file->private_data. This patch introduces a new wrapper for seq_lseek() which checks if the file descriptor is opened for reading first. If not, it does nothing. Signed-off-by:
Slava Pestov <slavapestov@google.com> LKML-Reference: <1290640396-24179-1-git-send-email-slavapestov@google.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@suse.de>
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NeilBrown authored
commit 1a855a06 upstream. With v0.90 metadata, a hot-spare does not become a full member of the array until recovery is complete. So if we re-add such a device to the array, we know that all of it is as up-to-date as the event count would suggest, and so it a bitmap-based recovery is possible. However with v1.x metadata, the hot-spare immediately becomes a full member of the array, but it record how much of the device has been recovered. If the array is stopped and re-assembled recovery starts from this point. When such a device is hot-added to an array we currently lose the 'how much is recovered' information and incorrectly included it as a full in-sync member (after bitmap-based fixup). This is wrong and unsafe and could corrupt data. So be more careful about setting saved_raid_disk - which is what guides the re-adding of devices back into an array. The new code matches the code in slot_store which does a similar thing, which is encouraging. This is suitable for any -stable kernel. Reported-by:
"Dailey, Nate" <Nate.Dailey@stratus.com> Signed-off-by:
NeilBrown <neilb@suse.de> Signed-off-by:
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Andreas Herrmann authored
[The mainline kernel doesn't have this problem. Commit "(23588c38) x86, amd: Add support for CPUID topology extension of AMD CPUs" removed the family check. But 2.6.32.y needs to be fixed.] This CPU family check is not required -- existence of the NodeId MSR is indicated by a CPUID feature flag which is already checked in amd_fixup_dcm() -- and it needlessly prevents amd_fixup_dcm() to be called for newer AMD CPUs. In worst case this can lead to a panic in the scheduler code for AMD family 0x15 multi-node AMD CPUs. I just have a picture of VGA console output so I can't copy-and-paste it herein, but the call stack of such a panic looked like: do_divide_error ... find_busiest_group run_rebalance_domains ... apic_timer_interrupt ... cpu_idle The mainline kernel doesn't have this problem. Commit "(23588c38) x86, amd: Add support for CPUID topology extension of AMD CPUs" removed the family check. But 2.6.32.y needs to be fixed. Signed-off-by:
Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by:
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David Kilroy authored
commit ba34fcee upstream. ... and interface up. In these situations, you are usually trying to connect to a new AP, so keeping TKIP countermeasures active is confusing. This is already how the driver behaves (inadvertently). However, querying SIOCGIWAUTH may tell userspace that countermeasures are active when they aren't. Clear the setting so that the reporting matches what the driver has done.. Signed-off by: David Kilroy <kilroyd@googlemail.com> Signed-off-by:
John W. Linville <linville@tuxdriver.com> Signed-off-by:
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David Kilroy authored
commit 0a54917c upstream. Enable the port when disabling countermeasures, and disable it on enabling countermeasures. This bug causes the response of the system to certain attacks to be ineffective. It also prevents wpa_supplicant from getting scan results, as wpa_supplicant disables countermeasures on startup - preventing the hardware from scanning. wpa_supplicant works with ap_mode=2 despite this bug because the commit handler re-enables the port. The log tends to look like: State: DISCONNECTED -> SCANNING Starting AP scan for wildcard SSID Scan requested (ret=0) - scan timeout 5 seconds EAPOL: disable timer tick EAPOL: Supplicant port status: Unauthorized Scan timeout - try to get results Failed to get scan results Failed to get scan results - try scanning again Setting scan request: 1 sec 0 usec Starting AP scan for wildcard SSID Scan requested (ret=-1) - scan timeout 5 seconds Failed to initiate AP scan. Reported by: Giacomo Comes <comes@naic.edu> Signed-off by: David Kilroy <kilroyd@googlemail.com> Signed-off-by:
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Alexey Starikovskiy authored
commit a5dc4f89 upstream. http://bugzilla.kernel.org/show_bug.cgi?id=15418Signed-off-by:
Alexey Starikovskiy <astarikovskiy@suse.de> Signed-off-by:
Len Brown <len.brown@intel.com> Signed-off-by:
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Bob Moore authored
commit 8df3fc98 upstream. Some Panasonic Toughbooks create nodes in module level code. Module level code is the executable AML code outside of control method, for example, below AML code creates a node \_SB.PCI0.GFX0.DD02.CUBL If (\_OSI ("Windows 2006")) { Scope (\_SB.PCI0.GFX0.DD02) { Name (CUBL, Ones) ... } } Scope() op does not actually create a new object, it refers to an existing object(\_SB.PCI0.GFX0.DD02 in above example). However, for Scope(), we want to indeed open a new scope, so the child nodes(CUBL in above example) can be created correctly under it. https://bugzilla.kernel.org/show_bug.cgi?id=19462Signed-off-by:
Bob Moore <robert.moore@intel.com> Signed-off-by:
Lin Ming <ming.m.lin@intel.com> Signed-off-by:
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Takashi Iwai authored
commit 1497dd1d upstream. The user-space hibernation sends a wrong notification after the image restoration because of thinko for the file flag check. RDONLY corresponds to hibernation and WRONLY to restoration, confusingly. Signed-off-by:
Takashi Iwai <tiwai@suse.de> Signed-off-by:
Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by:
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Dan Carpenter authored
commit 7182afea upstream. In ib_uverbs_poll_cq() code there is a potential integer overflow if userspace passes in a large cmd.ne. The calls to kmalloc() would allocate smaller buffers than intended, leading to memory corruption. There iss also an information leak if resp wasn't all used. Unprivileged userspace may call this function, although only if an RDMA device that uses this function is present. Fix this by copying CQ entries one at a time, which avoids the allocation entirely, and also by moving this copying into a function that makes sure to initialize all memory copied to userspace. Special thanks to Jason Gunthorpe <jgunthorpe@obsidianresearch.com> for his help and advice. Signed-off-by:
Dan Carpenter <error27@gmail.com> [ Monkey around with things a bit to avoid bad code generation by gcc when designated initializers are used. - Roland ] Signed-off-by:
Roland Dreier <rolandd@cisco.com> Signed-off-by:
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Borislav Petkov authored
commit e726f3c3 upstream. When matching error address to the range contained by one memory node, we're in valid range when node interleaving 1. is disabled, or 2. enabled and when the address bits we interleave on match the interleave selector on this node (see the "Node Interleaving" section in the BKDG for an enlightening example). Thus, when we early-exit, we need to reverse the compound logic statement properly. Signed-off-by:
Borislav Petkov <borislav.petkov@amd.com> Signed-off-by:
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Gabriele Gorla authored
commit 52bc9802 upstream. Prevent setting fan_div from stomping on other fans that share the same I2C register. Signed-off-by:
Gabriele Gorla <gorlik@penguintown.net> Signed-off-by:
Jean Delvare <khali@linux-fr.org> Signed-off-by:
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Gabriele Gorla authored
commit 8b0f1840 upstream. Allow 1 as a valid div value as specified in the ADM1026 datasheet. Signed-off-by:
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NeilBrown authored
commit ed2849d3 upstream. When an xprt is created, it has a refcount of 1, and XPT_BUSY is set. The refcount is *not* owned by the thread that created the xprt (as is clear from the fact that creators never put the reference). Rather, it is owned by the absence of XPT_DEAD. Once XPT_DEAD is set, (And XPT_BUSY is clear) that initial reference is dropped and the xprt can be freed. So when a creator clears XPT_BUSY it is dropping its only reference and so must not touch the xprt again. However svc_recv, after calling ->xpo_accept (and so getting an XPT_BUSY reference on a new xprt), calls svc_xprt_recieved. This clears XPT_BUSY and then svc_xprt_enqueue - this last without owning a reference. This is dangerous and has been seen to leave svc_xprt_enqueue working with an xprt containing garbage. So we need to hold an extra counted reference over that call to svc_xprt_received. For safety, any time we clear XPT_BUSY and then use the xprt again, we first get a reference, and the put it again afterwards. Note that svc_close_all does not need this extra protection as there are no threads running, and the final free can only be called asynchronously from such a thread. Signed-off-by:
J. Bruce Fields <bfields@redhat.com> Signed-off-by:
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Sergey Vlasov authored
commit 21ac19d4 upstream. The commit 129a84de (locks: fix F_GETLK regression (failure to find conflicts)) fixed the posix_test_lock() function by itself, however, its usage in NFS changed by the commit 9d6a8c5c (locks: give posix_test_lock same interface as ->lock) remained broken - subsequent NFS-specific locking code received F_UNLCK instead of the user-specified lock type. To fix the problem, fl->fl_type needs to be saved before the posix_test_lock() call and restored if no local conflicts were reported. Reference: https://bugzilla.kernel.org/show_bug.cgi?id=23892Tested-by:
Alexander Morozov <amorozov@etersoft.ru> Signed-off-by:
Sergey Vlasov <vsu@altlinux.ru> Signed-off-by:
Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by:
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Neil Brown authored
commit c1ac3ffc upstream. If vfs_getattr in fill_post_wcc returns an error, we don't set fh_post_change. For NFSv4, this can result in set_change_info triggering a BUG_ON. i.e. fh_post_saved being zero isn't really a bug. So: - instead of BUGging when fh_post_saved is zero, just clear ->atomic. - if vfs_getattr fails in fill_post_wcc, take a copy of i_ctime anyway. This will be used i seg_change_info, but not overly trusted. - While we are there, remove the pointless 'if' statements in set_change_info. There is no harm setting all the values. Signed-off-by:
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Chuck Lever authored
commit 5b362ac3 upstream. After a few unsuccessful NFS mount attempts in which the client and server cannot agree on an authentication flavor both support, the client panics. nfs_umount() is invoked in the kernel in this case. Turns out nfs_umount()'s UMNT RPC invocation causes the RPC client to write off the end of the rpc_clnt's iostat array. This is because the mount client's nrprocs field is initialized with the count of defined procedures (two: MNT and UMNT), rather than the size of the client's proc array (four). The fix is to use the same initialization technique used by most other upper layer clients in the kernel. Introduced by commit 0b524123, which failed to update nrprocs when support was added for UMNT in the kernel. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=24302 BugLink: http://bugs.launchpad.net/bugs/683938Reported-by:
Stefan Bader <stefan.bader@canonical.com> Tested-by:
Chuck Lever <chuck.lever@oracle.com> Signed-off-by:
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Heiko Carstens authored
commit dbd87b5a upstream. This fixes a bug as seen on 2.6.32 based kernels where timers got enqueued on offline cpus. If a cpu goes offline it might still have pending timers. These will be migrated during CPU_DEAD handling after the cpu is offline. However while the cpu is going offline it will schedule the idle task which will then call tick_nohz_stop_sched_tick(). That function in turn will call get_next_timer_intterupt() to figure out if the tick of the cpu can be stopped or not. If it turns out that the next tick is just one jiffy off (delta_jiffies == 1) tick_nohz_stop_sched_tick() incorrectly assumes that the tick should not stop and takes an early exit and thus it won't update the load balancer cpu. Just afterwards the cpu will be killed and the load balancer cpu could be the offline cpu. On 2.6.32 based kernel get_nohz_load_balancer() gets called to decide on which cpu a timer should be enqueued (see __mod_timer()). Which leads to the possibility that timers get enqueued on an offline cpu. These will never expire and can cause a system hang. This has been observed 2.6.32 kernels. On current kernels __mod_timer() uses get_nohz_timer_target() which doesn't have that problem. However there might be other problems because of the too early exit tick_nohz_stop_sched_tick() in case a cpu goes offline. The easiest and probably safest fix seems to be to let get_next_timer_interrupt() just lie and let it say there isn't any pending timer if the current cpu is offline. I also thought of moving migrate_[hr]timers() from CPU_DEAD to CPU_DYING, but seeing that there already have been fixes at least in the hrtimer code in this area I'm afraid that this could add new subtle bugs. Signed-off-by:
Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by:
Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20101201091109.GA8984@osiris.boeblingen.de.ibm.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu> Signed-off-by:
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Heiko Carstens authored
commit 61ab2544 upstream. This patch fixes a hang observed with 2.6.32 kernels where timers got enqueued on offline cpus. printk_needs_cpu() may return 1 if called on offline cpus. When a cpu gets offlined it schedules the idle process which, before killing its own cpu, will call tick_nohz_stop_sched_tick(). That function in turn will call printk_needs_cpu() in order to check if the local tick can be disabled. On offline cpus this function should naturally return 0 since regardless if the tick gets disabled or not the cpu will be dead short after. That is besides the fact that __cpu_disable() should already have made sure that no interrupts on the offlined cpu will be delivered anyway. In this case it prevents tick_nohz_stop_sched_tick() to call select_nohz_load_balancer(). No idea if that really is a problem. However what made me debug this is that on 2.6.32 the function get_nohz_load_balancer() is used within __mod_timer() to select a cpu on which a timer gets enqueued. If printk_needs_cpu() returns 1 then the nohz_load_balancer cpu doesn't get updated when a cpu gets offlined. It may contain the cpu number of an offline cpu. In turn timers get enqueued on an offline cpu and not very surprisingly they never expire and cause system hangs. This has been observed 2.6.32 kernels. On current kernels __mod_timer() uses get_nohz_timer_target() which doesn't have that problem. However there might be other problems because of the too early exit tick_nohz_stop_sched_tick() in case a cpu goes offline. Easiest way to fix this is just to test if the current cpu is offline and call printk_tick() directly which clears the condition. Alternatively I tried a cpu hotplug notifier which would clear the condition, however between calling the notifier function and printk_needs_cpu() something could have called printk() again and the problem is back again. This seems to be the safest fix. Signed-off-by:
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Alex Deucher authored
commit e76116ca upstream. Grub doesn't parse spaces in parameters correctly, so this makes it impossible to force video= parameters for kms on the grub kernel command line. v2: shorten the names to make them easier to type. Reported-by:
Sergej Pupykin <ml@sergej.pp.ru> Cc: Sergej Pupykin <ml@sergej.pp.ru> Signed-off-by:
Alex Deucher <alexdeucher@gmail.com> Signed-off-by:
Dave Airlie <airlied@redhat.com> Signed-off-by:
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Daniel T Chen authored
commit 77c4d5cd upstream. BugLink: https://launchpad.net/bugs/595482 The original reporter states that audible playback from the internal speaker is inaudible despite the hardware being properly detected. To work around this symptom, he uses the model=lg quirk to properly enable both playback, capture, and jack sense. Another user corroborates this workaround on separate hardware. Add this PCI SSID to the quirk table to enable it for further LG P1 Expresses. Reported-and-tested-by:
Philip Peitsch <philip.peitsch@gmail.com> Tested-by: nikhov Signed-off-by:
Daniel T Chen <crimsun@ubuntu.com> Signed-off-by:
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Miklos Szeredi authored
commit d9d318d3 upstream. If a 32bit CUSE server is run on 64bit this results in EIO being returned to the caller. The reason is that FUSE_IOCTL_RETRY reply was defined to use 'struct iovec', which is different on 32bit and 64bit archs. Work around this by looking at the size of the reply to determine which struct was used. This is only needed if CONFIG_COMPAT is defined. A more permanent fix for the interface will be to use the same struct on both 32bit and 64bit. Reported-by:
"ccmail111" <ccmail111@yahoo.com> Signed-off-by:
Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> Signed-off-by:
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Miklos Szeredi authored
commit 7572777e upstream. Verify that the total length of the iovec returned in FUSE_IOCTL_RETRY doesn't overflow iov_length(). Signed-off-by:
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H. Peter Anvin authored
upstream ea530692 x86, hotplug: Use mwait to offline a processor, fix the legacy case Here included also some small follow-on patches to the same code: upstream a68e5c94 x86, hotplug: Move WBINVD back outside the play_dead loop upstream ce5f6824 x86, hotplug: In the MWAIT case of play_dead, CLFLUSH the cache line https://bugzilla.kernel.org/show_bug.cgi?id=5471Signed-off-by:
H. Peter Anvin <hpa@linux.intel.com> Signed-off-by:
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Ben Hutchings authored
The backported version of "TTY: ldisc, fix open flag handling" in 2.6.32.27 causes tty_ldisc_open() to return 0 on error. Fix that. Signed-off-by:
Ben Hutchings <ben@decadent.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@linux.intel.com> Signed-off-by:
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- 09 Dec, 2010 16 commits
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Greg Kroah-Hartman authored
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Robin Holt authored
commit 15b87d67 upstream. Under heavy load conditions, our set of xpc messages may become exhausted. The code handles this correctly with the exception of the management code which hits a NULL pointer dereference. Signed-off-by:
Robin Holt <holt@sgi.com> Cc: Jack Steiner <steiner@sgi.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Robin Holt authored
commit dbd2918e upstream. Many times while the initial connection is being made, the contacted partition will send back both the ACTIVATING and the ACTIVE remote_act_state changes in very close succescion. The 1/4 second delay in the make first contact loop is large enough to nearly always miss the ACTIVATING state change. Since either state indicates the remote partition has acknowledged our state change, accept either. Signed-off-by:
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Robin Holt authored
commit 046d6c56 upstream. This was a difficult bug to trip. XPC was in the middle of sending an acknowledgement for a received message. In xpc_received_payload_uv(): . ret = xpc_send_gru_msg(ch->sn.uv.cached_notify_gru_mq_desc, msg, sizeof(struct xpc_notify_mq_msghdr_uv)); if (ret != xpSuccess) XPC_DEACTIVATE_PARTITION(&xpc_partitions[ch->partid], ret); msg->hdr.msg_slot_number += ch->remote_nentries; at the point in xpc_send_gru_msg() where the hardware has dispatched the acknowledgement, the remote side is able to reuse the message structure and send a message with a different slot number. This problem is made worse by interrupts. The adjustment of msg_slot_number and the BUG_ON in xpc_handle_notify_mq_msg_uv() which verifies the msg_slot_number is consistent are only used for debug purposes. Since a fix for this that preserves the debug functionality would either have to infringe upon the payload or allocate another structure just for debug, I decided to remove it entirely. Signed-off-by:
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Robin Holt authored
commit 57e6d258 upstream. Currently, the UV xpc code is passing nid to the gru_create_message_queue instead of nasid as it expects. Signed-off-by:
Jack Steiner <steiner@sgi.com> Signed-off-by:
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Eric Dumazet authored
commit 1c40be12 upstream. We leak at least 32bits of kernel memory to user land in tc dump, because we dont init all fields (capab ?) of the dumped structure. Use C99 initializers so that holes and non explicit fields are zeroed. Signed-off-by:
Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Cc: dann frazier <dannf@debian.org> Signed-off-by:
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Changli Gao authored
commit 504f85c9 upstream. act_nat: use stack variable structure tc_nat isn't too big for stack, so we can put it in stack. Signed-off-by:
Changli Gao <xiaosuo@gmail.com> Cc: dann frazier <dannf@debian.org> Signed-off-by:
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Heiko Carstens authored
commit e8129c64 upstream. On each machine check all registers are revalidated. The save area for the clock comparator however only contains the upper most seven bytes of the former contents, if valid. Therefore the machine check handler uses a store clock instruction to get the current time and writes that to the clock comparator register which in turn will generate an immediate timer interrupt. However within the lowcore the expected time of the next timer interrupt is stored. If the interrupt happens before that time the handler won't be called. In turn the clock comparator won't be reprogrammed and therefore the interrupt condition stays pending which causes an interrupt loop until the expected time is reached. On NOHZ machines this can result in unresponsive machines since the time of the next expected interrupted can be a couple of days in the future. To fix this just revalidate the clock comparator register with the expected value. In addition the special handling for udelay must be changed as well. Signed-off-by:
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David S. Miller authored
commit 8acfe468 upstream. This helps protect us from overflow issues down in the individual protocol sendmsg/recvmsg handlers. Once we hit INT_MAX we truncate out the rest of the iovec by setting the iov_len members to zero. This works because: 1) For SOCK_STREAM and SOCK_SEQPACKET sockets, partial writes are allowed and the application will just continue with another write to send the rest of the data. 2) For datagram oriented sockets, where there must be a one-to-one correspondance between write() calls and packets on the wire, INT_MAX is going to be far larger than the packet size limit the protocol is going to check for and signal with -EMSGSIZE. Based upon a patch by Linus Torvalds. Signed-off-by:
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Linus Torvalds authored
commit 253eacc0 upstream. Signed-off-by:
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Dan Rosenberg authored
commit 218854af upstream. In rds_cmsg_rdma_args(), the user-provided args->nr_local value is restricted to less than UINT_MAX. This seems to need a tighter upper bound, since the calculation of total iov_size can overflow, resulting in a small sock_kmalloc() allocation. This would probably just result in walking off the heap and crashing when calling rds_rdma_pages() with a high count value. If it somehow doesn't crash here, then memory corruption could occur soon after. Signed-off-by:
Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by:
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Phil Blundell authored
commit 16c41745 upstream. Add missing check for capable(CAP_NET_ADMIN) in SIOCSIFADDR operation. Signed-off-by:
Phil Blundell <philb@gnu.org> Signed-off-by:
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Phil Blundell authored
commit fa0e8464 upstream. Later parts of econet_sendmsg() rely on saddr != NULL, so return early with EINVAL if NULL was passed otherwise an oops may occur. Signed-off-by:
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H. Peter Anvin authored
commit 8848a910 upstream. Fix dummy inline stubs for trampoline-related functions when no trampolines exist (until we get rid of the no-trampoline case entirely.) Signed-off-by:
H. Peter Anvin <hpa@zytor.com> Cc: Joerg Roedel <joerg.roedel@amd.com> Cc: Borislav Petkov <borislav.petkov@amd.com> LKML-Reference: <4C6C294D.3030404@zytor.com> Signed-off-by:
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Hugh Dickins authored
commit b7d46089 upstream. rc2 kernel crashes when booting second cpu on this CONFIG_VMSPLIT_2G_OPT laptop: whereas cloning from kernel to low mappings pgd range does need to limit by both KERNEL_PGD_PTRS and KERNEL_PGD_BOUNDARY, cloning kernel pgd range itself must not be limited by the smaller KERNEL_PGD_BOUNDARY. Signed-off-by:
Hugh Dickins <hughd@google.com> LKML-Reference: <alpine.LSU.2.00.1008242235120.2515@sister.anvils> Signed-off-by:
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Joerg Roedel authored
commit fd89a137 upstream. This patch fixes machine crashes which occur when heavily exercising the CPU hotplug codepaths on a 32-bit kernel. These crashes are caused by AMD Erratum 383 and result in a fatal machine check exception. Here's the scenario: 1. On 32-bit, the swapper_pg_dir page table is used as the initial page table for booting a secondary CPU. 2. To make this work, swapper_pg_dir needs a direct mapping of physical memory in it (the low mappings). By adding those low, large page (2M) mappings (PAE kernel), we create the necessary conditions for Erratum 383 to occur. 3. Other CPUs which do not participate in the off- and onlining game may use swapper_pg_dir while the low mappings are present (when leave_mm is called). For all steps below, the CPU referred to is a CPU that is using swapper_pg_dir, and not the CPU which is being onlined. 4. The presence of the low mappings in swapper_pg_dir can result in TLB entries for addresses below __PAGE_OFFSET to be established speculatively. These TLB entries are marked global and large. 5. When the CPU with such TLB entry switches to another page table, this TLB entry remains because it is global. 6. The process then generates an access to an address covered by the above TLB entry but there is a permission mismatch - the TLB entry covers a large global page not accessible to userspace. 7. Due to this permission mismatch a new 4kb, user TLB entry gets established. Further, Erratum 383 provides for a small window of time where both TLB entries are present. This results in an uncorrectable machine check exception signalling a TLB multimatch which panics the machine. There are two ways to fix this issue: 1. Always do a global TLB flush when a new cr3 is loaded and the old page table was swapper_pg_dir. I consider this a hack hard to understand and with performance implications 2. Do not use swapper_pg_dir to boot secondary CPUs like 64-bit does. This patch implements solution 2. It introduces a trampoline_pg_dir which has the same layout as swapper_pg_dir with low_mappings. This page table is used as the initial page table of the booting CPU. Later in the bringup process, it switches to swapper_pg_dir and does a global TLB flush. This fixes the crashes in our test cases. -v2: switch to swapper_pg_dir right after entering start_secondary() so that we are able to access percpu data which might not be mapped in the trampoline page table. Signed-off-by:
Joerg Roedel <joerg.roedel@amd.com> LKML-Reference: <20100816123833.GB28147@aftab> Signed-off-by:
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