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2012-03-17lib: proportion: lower PROP_MAX_SHIFT to 32 on 64-bit kernelWu Fengguang
commit 3310225dfc71a35a2cc9340c15c0e08b14b3c754 upstream. PROP_MAX_SHIFT should be set to <=32 on 64-bit box. This fixes two bugs in the below lines of bdi_dirty_limit(): bdi_dirty *= numerator; do_div(bdi_dirty, denominator); 1) divide error: do_div() only uses the lower 32 bit of the denominator, which may trimmed to be 0 when PROP_MAX_SHIFT > 32. 2) overflow: (bdi_dirty * numerator) could easily overflow if numerator used up to 48 bits, leaving only 16 bits to bdi_dirty Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Reported-by: Ilya Tumaykin <librarian_rus@yahoo.com> Tested-by: Ilya Tumaykin <librarian_rus@yahoo.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Willy Tarreau <w@1wt.eu>
2012-02-11block: fail SCSI passthrough ioctls on partition devicesPaolo Bonzini
commit 0bfc96cb77224736dfa35c3c555d37b3646ef35e upstream. [ Changes with respect to 3.3: return -ENOTTY from scsi_verify_blk_ioctl and -ENOIOCTLCMD from sd_compat_ioctl. ] Linux allows executing the SG_IO ioctl on a partition or LVM volume, and will pass the command to the underlying block device. This is well-known, but it is also a large security problem when (via Unix permissions, ACLs, SELinux or a combination thereof) a program or user needs to be granted access only to part of the disk. This patch lets partitions forward a small set of harmless ioctls; others are logged with printk so that we can see which ioctls are actually sent. In my tests only CDROM_GET_CAPABILITY actually occurred. Of course it was being sent to a (partition on a) hard disk, so it would have failed with ENOTTY and the patch isn't changing anything in practice. Still, I'm treating it specially to avoid spamming the logs. In principle, this restriction should include programs running with CAP_SYS_RAWIO. If for example I let a program access /dev/sda2 and /dev/sdb, it still should not be able to read/write outside the boundaries of /dev/sda2 independent of the capabilities. However, for now programs with CAP_SYS_RAWIO will still be allowed to send the ioctls. Their actions will still be logged. This patch does not affect the non-libata IDE driver. That driver however already tests for bd != bd->bd_contains before issuing some ioctl; it could be restricted further to forbid these ioctls even for programs running with CAP_SYS_ADMIN/CAP_SYS_RAWIO. Cc: linux-scsi@vger.kernel.org Cc: Jens Axboe <axboe@kernel.dk> Cc: James Bottomley <JBottomley@parallels.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [ Make it also print the command name when warning - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backport to 2.6.32 - ENOIOCTLCMD does not get converted to ENOTTY, so we must return ENOTTY directly] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Willy Tarreau <w@1wt.eu>
2012-02-11block: add and use scsi_blk_cmd_ioctlPaolo Bonzini
commit 577ebb374c78314ac4617242f509e2f5e7156649 upstream. Introduce a wrapper around scsi_cmd_ioctl that takes a block device. The function will then be enhanced to detect partition block devices and, in that case, subject the ioctls to whitelisting. Cc: linux-scsi@vger.kernel.org Cc: Jens Axboe <axboe@kernel.dk> Cc: James Bottomley <JBottomley@parallels.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> [bwh: Backport to 2.6.32 - adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> [wt: slightly changed the interface to match 2.6.27's scsi_cmd_ioctl() which still needs the file pointer but has no mode parameter]. Signed-off-by: Willy Tarreau <w@1wt.eu>
2012-02-11af_packet: prevent information leakEric Dumazet
[ Upstream commit 13fcb7bd322164c67926ffe272846d4860196dc6 ] In 2.6.27, commit 393e52e33c6c2 (packet: deliver VLAN TCI to userspace) added a small information leak. Add padding field and make sure its zeroed before copy to user. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Willy Tarreau <w@1wt.eu>
2012-02-11x86, 64-bit: Fix copy_[to/from]_user() checks for the userspace address limitJiri Olsa
commit 26afb7c661080ae3f1f13ddf7f0c58c4f931c22b upstream. As reported in BZ #30352: https://bugzilla.kernel.org/show_bug.cgi?id=30352 there's a kernel bug related to reading the last allowed page on x86_64. The _copy_to_user() and _copy_from_user() functions use the following check for address limit: if (buf + size >= limit) fail(); while it should be more permissive: if (buf + size > limit) fail(); That's because the size represents the number of bytes being read/write from/to buf address AND including the buf address. So the copy function will actually never touch the limit address even if "buf + size == limit". Following program fails to use the last page as buffer due to the wrong limit check: #include <sys/mman.h> #include <sys/socket.h> #include <assert.h> #define PAGE_SIZE (4096) #define LAST_PAGE ((void*)(0x7fffffffe000)) int main() { int fds[2], err; void * ptr = mmap(LAST_PAGE, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); assert(ptr == LAST_PAGE); err = socketpair(AF_LOCAL, SOCK_STREAM, 0, fds); assert(err == 0); err = send(fds[0], ptr, PAGE_SIZE, 0); perror("send"); assert(err == PAGE_SIZE); err = recv(fds[1], ptr, PAGE_SIZE, MSG_WAITALL); perror("recv"); assert(err == PAGE_SIZE); return 0; } The other place checking the addr limit is the access_ok() function, which is working properly. There's just a misleading comment for the __range_not_ok() macro - which this patch fixes as well. The last page of the user-space address range is a guard page and Brian Gerst observed that the guard page itself due to an erratum on K8 cpus (#121 Sequential Execution Across Non-Canonical Boundary Causes Processor Hang). However, the test code is using the last valid page before the guard page. The bug is that the last byte before the guard page can't be read because of the off-by-one error. The guard page is left in place. This bug would normally not show up because the last page is part of the process stack and never accessed via syscalls. [WT: in 2.6.27 use include/asm-x86/uaccess.h] Signed-off-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Brian Gerst <brgerst@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1305210630-7136-1-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Willy Tarreau <w@1wt.eu>
2012-02-11x86, mm: Add __get_user_pages_fast()Peter Zijlstra
Introduce a gup_fast() variant which is usable from IRQ/NMI context. [ WT: this one is only needed for next patch ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> CC: Nick Piggin <npiggin@suse.de> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Willy Tarreau <w@1wt.eu>
2012-02-11NLM: Don't hang forever on NLM unlock requestsTrond Myklebust
commit 0b760113a3a155269a3fba93a409c640031dd68f upstream. If the NLM daemon is killed on the NFS server, we can currently end up hanging forever on an 'unlock' request, instead of aborting. Basically, if the rpcbind request fails, or the server keeps returning garbage, we really want to quit instead of retrying. Tested-by: Vasily Averin <vvs@sw.ru> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Willy Tarreau <w@1wt.eu>
2012-02-11seqlock: Don't smp_rmb in seqlock reader spin loopMilton Miller
commit 5db1256a5131d3b133946fa02ac9770a784e6eb2 upstream. Move the smp_rmb after cpu_relax loop in read_seqlock and add ACCESS_ONCE to make sure the test and return are consistent. A multi-threaded core in the lab didn't like the update from 2.6.35 to 2.6.36, to the point it would hang during boot when multiple threads were active. Bisection showed af5ab277ded04bd9bc6b048c5a2f0e7d70ef0867 (clockevents: Remove the per cpu tick skew) as the culprit and it is supported with stack traces showing xtime_lock waits including tick_do_update_jiffies64 and/or update_vsyscall. Experimentation showed the combination of cpu_relax and smp_rmb was significantly slowing the progress of other threads sharing the core, and this patch is effective in avoiding the hang. A theory is the rmb is affecting the whole core while the cpu_relax is causing a resource rebalance flush, together they cause an interfernce cadance that is unbroken when the seqlock reader has interrupts disabled. At first I was confused why the refactor in 3c22cd5709e8143444a6d08682a87f4c57902df3 (kernel: optimise seqlock) didn't affect this patch application, but after some study that affected seqcount not seqlock. The new seqcount was not factored back into the seqlock. I defer that the future. While the removal of the timer interrupt offset created contention for the xtime lock while a cpu does the additonal work to update the system clock, the seqlock implementation with the tight rmb spin loop goes back much further, and is just waiting for the right trigger. Signed-off-by: Milton Miller <miltonm@bga.com> Cc: <linuxppc-dev@lists.ozlabs.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Anton Blanchard <anton@samba.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Link: http://lkml.kernel.org/r/%3Cseqlock-rmb%40mdm.bga.com%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Willy Tarreau <w@1wt.eu>
2011-04-30next_pidmap: fix overflow conditionLinus Torvalds
commit c78193e9c7bcbf25b8237ad0dec82f805c4ea69b upstream. next_pidmap() just quietly accepted whatever 'last' pid that was passed in, which is not all that safe when one of the users is /proc. Admittedly the proc code should do some sanity checking on the range (and that will be the next commit), but that doesn't mean that the helper functions should just do that pidmap pointer arithmetic without checking the range of its arguments. So clamp 'last' to PID_MAX_LIMIT. The fact that we then do "last+1" doesn't really matter, the for-loop does check against the end of the pidmap array properly (it's only the actual pointer arithmetic overflow case we need to worry about, and going one bit beyond isn't going to overflow). [ Use PID_MAX_LIMIT rather than pid_max as per Eric Biederman ] Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com> Analyzed-by: Robert Święcki <robert@swiecki.net> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30exec: copy-and-paste the fixes into compat_do_execve() pathsOleg Nesterov
commit 114279be2120a916e8a04feeb2ac976a10016f2f upstream. Note: this patch targets 2.6.37 and tries to be as simple as possible. That is why it adds more copy-and-paste horror into fs/compat.c and uglifies fs/exec.c, this will be cleanuped later. compat_copy_strings() plays with bprm->vma/mm directly and thus has two problems: it lacks the RLIMIT_STACK check and argv/envp memory is not visible to oom killer. Export acct_arg_size() and get_arg_page(), change compat_copy_strings() to use get_arg_page(), change compat_do_execve() to do acct_arg_size(0) as do_execve() does. Add the fatal_signal_pending/cond_resched checks into compat_count() and compat_copy_strings(), this matches the code in fs/exec.c and certainly makes sense. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Moritz Muehlenhoff <jmm@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30exec: make argv/envp memory visible to oom-killerOleg Nesterov
commit 3c77f845722158206a7209c45ccddc264d19319c upstream. Brad Spengler published a local memory-allocation DoS that evades the OOM-killer (though not the virtual memory RLIMIT): http://www.grsecurity.net/~spender/64bit_dos.c execve()->copy_strings() can allocate a lot of memory, but this is not visible to oom-killer, nobody can see the nascent bprm->mm and take it into account. With this patch get_arg_page() increments current's MM_ANONPAGES counter every time we allocate the new page for argv/envp. When do_execve() succeds or fails, we change this counter back. Technically this is not 100% correct, we can't know if the new page is swapped out and turn MM_ANONPAGES into MM_SWAPENTS, but I don't think this really matters and everything becomes correct once exec changes ->mm or fails. Reported-by: Brad Spengler <spender@grsecurity.net> Reviewed-and-discussed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Moritz Muehlenhoff <jmm@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30ASoC: Explicitly say registerless widgets have no registerMark Brown
commit 0ca03cd7d0fa3bfbd56958136a10f19733c4ce12 upstream. This stops code that handles widgets generically from attempting to access registers for these widgets. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Liam Girdwood <lrg@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30ses: Avoid kernel panic when lun 0 is not mappedKrishnasamy, Somasundaram
commit d1e12de804f9d8ad114786ca7c2ce593cba79891 upstream. During device discovery, scsi mid layer sends INQUIRY command to LUN 0. If the LUN 0 is not mapped to host, it creates a temporary scsi_device with LUN id 0 and sends REPORT_LUNS command to it. After the REPORT_LUNS succeeds, it walks through the LUN table and adds each LUN found to sysfs. At the end of REPORT_LUNS lun table scan, it will delete the temporary scsi_device of LUN 0. When scsi devices are added to sysfs, it calls add_dev function of all the registered class interfaces. If ses driver has been registered, ses_intf_add() of ses module will be called. This function calls scsi_device_enclosure() to check the inquiry data for EncServ bit. Since inquiry was not allocated for temporary LUN 0 scsi_device, it will cause NULL pointer exception. To fix the problem, sdev->inquiry is checked for NULL before reading it. Signed-off-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com> Signed-off-by: Babu Moger <babu.moger@lsi.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30x86: Flush TLB if PGD entry is changed in i386 PAE modeShaohua Li
commit 4981d01eada5354d81c8929d5b2836829ba3df7b upstream. According to intel CPU manual, every time PGD entry is changed in i386 PAE mode, we need do a full TLB flush. Current code follows this and there is comment for this too in the code. But current code misses the multi-threaded case. A changed page table might be used by several CPUs, every such CPU should flush TLB. Usually this isn't a problem, because we prepopulate all PGD entries at process fork. But when the process does munmap and follows new mmap, this issue will be triggered. When it happens, some CPUs keep doing page faults: http://marc.info/?l=linux-kernel&m=129915020508238&w=2 Reported-by: Yasunori Goto<y-goto@jp.fujitsu.com> Tested-by: Yasunori Goto<y-goto@jp.fujitsu.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Shaohua Li<shaohua.li@intel.com> Cc: Mallick Asit K <asit.k.mallick@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mm <linux-mm@kvack.org> LKML-Reference: <1300246649.2337.95.camel@sli10-conroe> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30sctp: Fix oops when sending queued ASCONF chunksVlad Yasevich
commit c0786693404cffd80ca3cb6e75ee7b35186b2825 upstream. When we finish processing ASCONF_ACK chunk, we try to send the next queued ASCONF. This action runs the sctp state machine recursively and it's not prepared to do so. kernel BUG at kernel/timer.c:790! invalid opcode: 0000 [#1] SMP last sysfs file: /sys/module/ipv6/initstate Modules linked in: sha256_generic sctp libcrc32c ipv6 dm_multipath uinput 8139too i2c_piix4 8139cp mii i2c_core pcspkr virtio_net joydev floppy virtio_blk virtio_pci [last unloaded: scsi_wait_scan] Pid: 0, comm: swapper Not tainted 2.6.34-rc4 #15 /Bochs EIP: 0060:[<c044a2ef>] EFLAGS: 00010286 CPU: 0 EIP is at add_timer+0xd/0x1b EAX: cecbab14 EBX: 000000f0 ECX: c0957b1c EDX: 03595cf4 ESI: cecba800 EDI: cf276f00 EBP: c0957aa0 ESP: c0957aa0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 Process swapper (pid: 0, ti=c0956000 task=c0988ba0 task.ti=c0956000) Stack: c0957ae0 d1851214 c0ab62e4 c0ab5f26 0500ffff 00000004 00000005 00000004 <0> 00000000 d18694fd 00000004 1666b892 cecba800 cecba800 c0957b14 00000004 <0> c0957b94 d1851b11 ceda8b00 cecba800 cf276f00 00000001 c0957b14 000000d0 Call Trace: [<d1851214>] ? sctp_side_effects+0x607/0xdfc [sctp] [<d1851b11>] ? sctp_do_sm+0x108/0x159 [sctp] [<d1863386>] ? sctp_pname+0x0/0x1d [sctp] [<d1861a56>] ? sctp_primitive_ASCONF+0x36/0x3b [sctp] [<d185657c>] ? sctp_process_asconf_ack+0x2a4/0x2d3 [sctp] [<d184e35c>] ? sctp_sf_do_asconf_ack+0x1dd/0x2b4 [sctp] [<d1851ac1>] ? sctp_do_sm+0xb8/0x159 [sctp] [<d1863334>] ? sctp_cname+0x0/0x52 [sctp] [<d1854377>] ? sctp_assoc_bh_rcv+0xac/0xe1 [sctp] [<d1858f0f>] ? sctp_inq_push+0x2d/0x30 [sctp] [<d186329d>] ? sctp_rcv+0x797/0x82e [sctp] Tested-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: Yuansong Qiao <ysqiao@research.ait.ie> Signed-off-by: Shuaijun Zhang <szhang@research.ait.ie> Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: maximilian attems <max@stro.at> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30x86: Use u32 instead of long to set reset vector back to 0Don Zickus
commit 299c56966a72b9109d47c71a6db52097098703dd upstream. A customer of ours, complained that when setting the reset vector back to 0, it trashed other data and hung their box. They noticed when only 4 bytes were set to 0 instead of 8, everything worked correctly. Mathew pointed out: | | We're supposed to be resetting trampoline_phys_low and | trampoline_phys_high here, which are two 16-bit values. | Writing 64 bits is definitely going to overwrite space | that we're not supposed to be touching. | So limit the area modified to u32. Signed-off-by: Don Zickus <dzickus@redhat.com> Acked-by: Matthew Garrett <mjg@redhat.com> LKML-Reference: <1297139100-424-1-git-send-email-dzickus@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30x86, mm: avoid possible bogus tlb entries by clearing prev mm_cpumask after ↵Suresh Siddha
switching mm commit 831d52bc153971b70e64eccfbed2b232394f22f8 upstream. Clearing the cpu in prev's mm_cpumask early will avoid the flush tlb IPI's while the cr3 is still pointing to the prev mm. And this window can lead to the possibility of bogus TLB fills resulting in strange failures. One such problematic scenario is mentioned below. T1. CPU-1 is context switching from mm1 to mm2 context and got a NMI etc between the point of clearing the cpu from the mm_cpumask(mm1) and before reloading the cr3 with the new mm2. T2. CPU-2 is tearing down a specific vma for mm1 and will proceed with flushing the TLB for mm1. It doesn't send the flush TLB to CPU-1 as it doesn't see that cpu listed in the mm_cpumask(mm1). T3. After the TLB flush is complete, CPU-2 goes ahead and frees the page-table pages associated with the removed vma mapping. T4. CPU-2 now allocates those freed page-table pages for something else. T5. As the CR3 and TLB caches for mm1 is still active on CPU-1, CPU-1 can potentially speculate and walk through the page-table caches and can insert new TLB entries. As the page-table pages are already freed and being used on CPU-2, this page walk can potentially insert a bogus global TLB entry depending on the (random) contents of the page that is being used on CPU-2. T6. This bogus TLB entry being global will be active across future CR3 changes and can result in weird memory corruption etc. To avoid this issue, for the prev mm that is handing over the cpu to another mm, clear the cpu from the mm_cpumask(prev) after the cr3 is changed. Marking it for -stable, though we haven't seen any reported failure that can be attributed to this. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-30drm/radeon: remove 0x4243 pci idAlex Deucher
commit 63a507800c8aca5a1891d598ae13f829346e8e39 upstream. 0x4243 is a PCI bridge, not a GPU. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=33815 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-09sctp: Fix a race between ICMP protocol unreachable and connect()Vlad Yasevich
commit 50b5d6ad63821cea324a5a7a19854d4de1a0a819 upstream. ICMP protocol unreachable handling completely disregarded the fact that the user may have locked the socket. It proceeded to destroy the association, even though the user may have held the lock and had a ref on the association. This resulted in the following: Attempt to release alive inet socket f6afcc00 ========================= [ BUG: held lock freed! ] ------------------------- somenu/2672 is freeing memory f6afcc00-f6afcfff, with a lock still held there! (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c 1 lock held by somenu/2672: #0: (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c stack backtrace: Pid: 2672, comm: somenu Not tainted 2.6.32-telco #55 Call Trace: [<c1232266>] ? printk+0xf/0x11 [<c1038553>] debug_check_no_locks_freed+0xce/0xff [<c10620b4>] kmem_cache_free+0x21/0x66 [<c1185f25>] __sk_free+0x9d/0xab [<c1185f9c>] sk_free+0x1c/0x1e [<c1216e38>] sctp_association_put+0x32/0x89 [<c1220865>] __sctp_connect+0x36d/0x3f4 [<c122098a>] ? sctp_connect+0x13/0x4c [<c102d073>] ? autoremove_wake_function+0x0/0x33 [<c12209a8>] sctp_connect+0x31/0x4c [<c11d1e80>] inet_dgram_connect+0x4b/0x55 [<c11834fa>] sys_connect+0x54/0x71 [<c103a3a2>] ? lock_release_non_nested+0x88/0x239 [<c1054026>] ? might_fault+0x42/0x7c [<c1054026>] ? might_fault+0x42/0x7c [<c11847ab>] sys_socketcall+0x6d/0x178 [<c10da994>] ? trace_hardirqs_on_thunk+0xc/0x10 [<c1002959>] syscall_call+0x7/0xb This was because the sctp_wait_for_connect() would aqcure the socket lock and then proceed to release the last reference count on the association, thus cause the fully destruction path to finish freeing the socket. The simplest solution is to start a very short timer in case the socket is owned by user. When the timer expires, we can do some verification and be able to do the release properly. Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Willy Tarreau <w@1wt.eu>
2011-02-09nfsd: Fix possible BUG_ON firing in set_change_infoNeil Brown
commit c1ac3ffcd0bc7e9617f62be8c7043d53ab84deac 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: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Willy Tarreau <w@1wt.eu>
2010-12-09x25: Patch to fix bug 15678 - x25 accesses fields beyond end of packet.John Hughes
commit f5eb917b861828da18dc28854308068c66d1449a upstream. Here is a patch to stop X.25 examining fields beyond the end of the packet. For example, when a simple CALL ACCEPTED was received: 10 10 0f x25_parse_facilities was attempting to decode the FACILITIES field, but this packet contains no facilities field. Signed-off-by: John Hughes <john@calva.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-28guard page for stacks that grow upwardsLuck, Tony
commit 8ca3eb08097f6839b2206e2242db4179aee3cfb3 upstream. pa-risc and ia64 have stacks that grow upwards. Check that they do not run into other mappings. By making VM_GROWSUP 0x0 on architectures that do not ever use it, we can avoid some unpleasant #ifdefs in check_stack_guard_page(). Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: dann frazier <dannf@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-09-20compat: Make compat_alloc_user_space() incorporate the access_ok()H. Peter Anvin
commit c41d68a513c71e35a14f66d71782d27a79a81ea6 upstream. compat_alloc_user_space() expects the caller to independently call access_ok() to verify the returned area. A missing call could introduce problems on some architectures. This patch incorporates the access_ok() check into compat_alloc_user_space() and also adds a sanity check on the length. The existing compat_alloc_user_space() implementations are renamed arch_compat_alloc_user_space() and are used as part of the implementation of the new global function. This patch assumes NULL will cause __get_user()/__put_user() to either fail or access userspace on all architectures. This should be followed by checking the return value of compat_access_user_space() for NULL in the callers, at which time the access_ok() in the callers can also be removed. Reported-by: Ben Hawkes <hawkes@sota.gen.nz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: James Bottomley <jejb@parisc-linux.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-02math-emu: correct test for downshifting fraction in _FP_FROM_INT()Mikael Pettersson
commit f8324e20f8289dffc646d64366332e05eaacab25 upstream. The kernel's math-emu code contains a macro _FP_FROM_INT() which is used to convert an integer to a raw normalized floating-point value. It does this basically in three steps: 1. Compute the exponent from the number of leading zero bits. 2. Downshift large fractions to put the MSB in the right position for normalized fractions. 3. Upshift small fractions to put the MSB in the right position. There is an boundary error in step 2, causing a fraction with its MSB exactly one bit above the normalized MSB position to not be downshifted. This results in a non-normalized raw float, which when packed becomes a massively inaccurate representation for that input. The impact of this depends on a number of arch-specific factors, but it is known to have broken emulation of FXTOD instructions on UltraSPARC III, which was originally reported as GCC bug 44631 <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44631>. Any arch which uses math-emu to emulate conversions from integers to same-size floats may be affected. The fix is simple: the exponent comparison used to determine if the fraction should be downshifted must be "<=" not "<". I'm sending a kernel module to test this as a reply to this message. There are also SPARC user-space test cases in the GCC bug entry. Signed-off-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-05vfs: add NOFOLLOW flag to umount(2)Miklos Szeredi
commit db1f05bb85d7966b9176e293f3ceead1cb8b5d79 upstream. Add a new UMOUNT_NOFOLLOW flag to umount(2). This is needed to prevent symlink attacks in unprivileged unmounts (fuse, samba, ncpfs). Additionally, return -EINVAL if an unknown flag is used (and specify an explicitly unused flag: UMOUNT_UNUSED). This makes it possible for the caller to determine if a flag is supported or not. CC: Eugene Teo <eugene@redhat.com> CC: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-05sctp: Fix skb_over_panic resulting from multiple invalid parameter errors ↵Neil Horman
(CVE-2010-1173) (v4) commit 5fa782c2f5ef6c2e4f04d3e228412c9b4a4c8809 upstream. Ok, version 4 Change Notes: 1) Minor cleanups, from Vlads notes Summary: Hey- Recently, it was reported to me that the kernel could oops in the following way: <5> kernel BUG at net/core/skbuff.c:91! <5> invalid operand: 0000 [#1] <5> Modules linked in: sctp netconsole nls_utf8 autofs4 sunrpc iptable_filter ip_tables cpufreq_powersave parport_pc lp parport vmblock(U) vsock(U) vmci(U) vmxnet(U) vmmemctl(U) vmhgfs(U) acpiphp dm_mirror dm_mod button battery ac md5 ipv6 uhci_hcd ehci_hcd snd_ens1371 snd_rawmidi snd_seq_device snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc snd_ac97_codec snd soundcore pcnet32 mii floppy ext3 jbd ata_piix libata mptscsih mptsas mptspi mptscsi mptbase sd_mod scsi_mod <5> CPU: 0 <5> EIP: 0060:[<c02bff27>] Not tainted VLI <5> EFLAGS: 00010216 (2.6.9-89.0.25.EL) <5> EIP is at skb_over_panic+0x1f/0x2d <5> eax: 0000002c ebx: c033f461 ecx: c0357d96 edx: c040fd44 <5> esi: c033f461 edi: df653280 ebp: 00000000 esp: c040fd40 <5> ds: 007b es: 007b ss: 0068 <5> Process swapper (pid: 0, threadinfo=c040f000 task=c0370be0) <5> Stack: c0357d96 e0c29478 00000084 00000004 c033f461 df653280 d7883180 e0c2947d <5> 00000000 00000080 df653490 00000004 de4f1ac0 de4f1ac0 00000004 df653490 <5> 00000001 e0c2877a 08000800 de4f1ac0 df653490 00000000 e0c29d2e 00000004 <5> Call Trace: <5> [<e0c29478>] sctp_addto_chunk+0xb0/0x128 [sctp] <5> [<e0c2947d>] sctp_addto_chunk+0xb5/0x128 [sctp] <5> [<e0c2877a>] sctp_init_cause+0x3f/0x47 [sctp] <5> [<e0c29d2e>] sctp_process_unk_param+0xac/0xb8 [sctp] <5> [<e0c29e90>] sctp_verify_init+0xcc/0x134 [sctp] <5> [<e0c20322>] sctp_sf_do_5_1B_init+0x83/0x28e [sctp] <5> [<e0c25333>] sctp_do_sm+0x41/0x77 [sctp] <5> [<c01555a4>] cache_grow+0x140/0x233 <5> [<e0c26ba1>] sctp_endpoint_bh_rcv+0xc5/0x108 [sctp] <5> [<e0c2b863>] sctp_inq_push+0xe/0x10 [sctp] <5> [<e0c34600>] sctp_rcv+0x454/0x509 [sctp] <5> [<e084e017>] ipt_hook+0x17/0x1c [iptable_filter] <5> [<c02d005e>] nf_iterate+0x40/0x81 <5> [<c02e0bb9>] ip_local_deliver_finish+0x0/0x151 <5> [<c02e0c7f>] ip_local_deliver_finish+0xc6/0x151 <5> [<c02d0362>] nf_hook_slow+0x83/0xb5 <5> [<c02e0bb2>] ip_local_deliver+0x1a2/0x1a9 <5> [<c02e0bb9>] ip_local_deliver_finish+0x0/0x151 <5> [<c02e103e>] ip_rcv+0x334/0x3b4 <5> [<c02c66fd>] netif_receive_skb+0x320/0x35b <5> [<e0a0928b>] init_stall_timer+0x67/0x6a [uhci_hcd] <5> [<c02c67a4>] process_backlog+0x6c/0xd9 <5> [<c02c690f>] net_rx_action+0xfe/0x1f8 <5> [<c012a7b1>] __do_softirq+0x35/0x79 <5> [<c0107efb>] handle_IRQ_event+0x0/0x4f <5> [<c01094de>] do_softirq+0x46/0x4d Its an skb_over_panic BUG halt that results from processing an init chunk in which too many of its variable length parameters are in some way malformed. The problem is in sctp_process_unk_param: if (NULL == *errp) *errp = sctp_make_op_error_space(asoc, chunk, ntohs(chunk->chunk_hdr->length)); if (*errp) { sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM, WORD_ROUND(ntohs(param.p->length))); sctp_addto_chunk(*errp, WORD_ROUND(ntohs(param.p->length)), param.v); When we allocate an error chunk, we assume that the worst case scenario requires that we have chunk_hdr->length data allocated, which would be correct nominally, given that we call sctp_addto_chunk for the violating parameter. Unfortunately, we also, in sctp_init_cause insert a sctp_errhdr_t structure into the error chunk, so the worst case situation in which all parameters are in violation requires chunk_hdr->length+(sizeof(sctp_errhdr_t)*param_count) bytes of data. The result of this error is that a deliberately malformed packet sent to a listening host can cause a remote DOS, described in CVE-2010-1173: http://cve.mitre.org/cgi-bin/cvename.cgi?name=2010-1173 I've tested the below fix and confirmed that it fixes the issue. We move to a strategy whereby we allocate a fixed size error chunk and ignore errors we don't have space to report. Tested by me successfully Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-26nfsd: fix vm overcommit crash fix #2Junjiro R. Okajima
commit 1b79cd04fab80be61dcd2732e2423aafde9a4c1c upstream. The previous patch from Alan Cox ("nfsd: fix vm overcommit crash", commit 731572d39fcd3498702eda4600db4c43d51e0b26) fixed the problem where knfsd crashes on exported shmemfs objects and strict overcommit is set. But the patch forgot supporting the case when CONFIG_SECURITY is disabled. This patch copies a part of his fix which is mainly for detecting a bug earlier. Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Junjiro R. Okajima <hooanon05@yahoo.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-26nfsd: fix vm overcommit crashAlan Cox
commit 731572d39fcd3498702eda4600db4c43d51e0b26 upstream. Junjiro R. Okajima reported a problem where knfsd crashes if you are using it to export shmemfs objects and run strict overcommit. In this situation the current->mm based modifier to the overcommit goes through a NULL pointer. We could simply check for NULL and skip the modifier but we've caught other real bugs in the past from mm being NULL here - cases where we did need a valid mm set up (eg the exec bug about a year ago). To preserve the checks and get the logic we want shuffle the checking around and add a new helper to the vm_ security wrappers Also fix a current->mm reference in nommu that should use the passed mm [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix build] Reported-by: Junjiro R. Okajima <hooanon05@yahoo.co.jp> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-26vfs: Remove the range_cont writeback mode.Aneesh Kumar K.V
commit 74baaaaec8b4f22e1ae279f5ecca4ff705b28912 upstream. Ext4 was the only user of range_cont writeback mode and ext4 switched to a different method. So remove the range_cont mode which is not used in the kernel. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> CC: linux-fsdevel@vger.kernel.org Signed-off-by: Jayson R. King <dev@jaysonking.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-26percpu counter: clean up percpu_counter_sum_and_set()Mingming Cao
commit 1f7c14c62ce63805f9574664a6c6de3633d4a354 upstream. percpu_counter_sum_and_set() and percpu_counter_sum() is the same except the former updates the global counter after accounting. Since we are taking the fbc->lock to calculate the precise value of the counter in percpu_counter_sum() anyway, it should simply set fbc->count too, as the percpu_counter_sum_and_set() does. This patch merges these two interfaces into one. Signed-off-by: Mingming Cao <cmm@us.ibm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Jayson R. King <dev@jaysonking.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2010-04-01KVM: VMX: Check cpl before emulating debug register accessAvi Kivity
commit 0a79b009525b160081d75cef5dbf45817956acf2 upstream. Debug registers may only be accessed from cpl 0. Unfortunately, vmx will code to emulate the instruction even though it was issued from guest userspace, possibly leading to an unexpected trap later. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01KVM: x86 emulator: limit instructions to 15 bytesAvi Kivity
commit eb3c79e64a70fb8f7473e30fa07e89c1ecc2c9bb upstream [ <cebbert@redhat.com>: backport to 2.6.27 ] While we are never normally passed an instruction that exceeds 15 bytes, smp games can cause us to attempt to interpret one, which will cause large latencies in non-preempt hosts. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01sched: wakeup preempt when small overlapPeter Zijlstra
commit 15afe09bf496ae10c989e1a375a6b5da7bd3e16e upstream. Lin Ming reported a 10% OLTP regression against 2.6.27-rc4. The difference seems to come from different preemption agressiveness, which affects the cache footprint of the workload and its effective cache trashing. Aggresively preempt a task if its avg overlap is very small, this should avoid the task going to sleep and find it still running when we schedule back to it - saving a wakeup. Reported-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01sched: fine-tune SD_SIBLING_INITIngo Molnar
commit 52c642f33b14bfa1b00ef2b68296effb34a573f3 upstream. fine-tune the HT sched-domains parameters as well. On a HT capable box, this increases lat_ctx performance from 23.87 usecs to 1.49 usecs: # before $ ./lat_ctx -s 0 2 "size=0k ovr=1.89 2 23.87 # after $ ./lat_ctx -s 0 2 "size=0k ovr=1.84 2 1.49 Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01sched: fine-tune SD_MC_INITMike Galbraith
commit 14800984706bf6936bbec5187f736e928be5c218 upstream. Tune SD_MC_INIT the same way as SD_CPU_INIT: unset SD_BALANCE_NEWIDLE, and set SD_WAKE_BALANCE. This improves vmark by 5%: vmark 132102 125968 125497 messages/sec avg 127855.66 .984 vmark 139404 131719 131272 messages/sec avg 134131.66 1.033 Signed-off-by: Mike Galbraith <efault@gmx.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01x86: fix csum_ipv6_magic asm memory clobberSamuel Thibault
commit 392d814daf460a9564d29b2cebc51e1ea34e0504 upstream. Just like ip_fast_csum, the assembly snippet in csum_ipv6_magic needs a memory clobber, as it is only passed the address of the buffer, not a memory reference to the buffer itself. This caused failures in Hurd's pfinetv4 when we tried to compile it with gcc-4.3 (bogus checksums). Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Acked-by: "David S. Miller" <davem@davemloft.net> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01resource: add helpers for fetching rlimitsJiri Slaby
commit 3e10e716abf3c71bdb5d86b8f507f9e72236c9cd upstream. We want to be sure that compiler fetches the limit variable only once, so add helpers for fetching current and maximal resource limits which do that. Add them to sched.h (instead of resource.h) due to circular dependency sched.h->resource.h->task_struct Alternative would be to create a separate res_access.h or similar. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: James Morris <jmorris@namei.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-06ipv6: reassembly: use seperate reassembly queues for conntrack and local ↵Patrick McHardy
delivery commit 0b5ccb2ee250136dd7385b1c7da28417d0d4d32d upstream. Currently the same reassembly queue might be used for packets reassembled by conntrack in different positions in the stack (PREROUTING/LOCAL_OUT), as well as local delivery. This can cause "packet jumps" when the fragment completing a reassembled packet is queued from a different position in the stack than the previous ones. Add a "user" identifier to the reassembly queue key to seperate the queues of each caller, similar to what we do for IPv4. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18signal: Fix alternate signal stack checkSebastian Andrzej Siewior
commit 2a855dd01bc1539111adb7233f587c5c468732ac upstream. All architectures in the kernel increment/decrement the stack pointer before storing values on the stack. On architectures which have the stack grow down sas_ss_sp == sp is not on the alternate signal stack while sas_ss_sp + sas_ss_size == sp is on the alternate signal stack. On architectures which have the stack grow up sas_ss_sp == sp is on the alternate signal stack while sas_ss_sp + sas_ss_size == sp is not on the alternate signal stack. The current implementation fails for architectures which have the stack grow down on the corner case where sas_ss_sp == sp.This was reported as Debian bug #544905 on AMD64. Simplified test case: http://download.breakpoint.cc/tc-sig-stack.c The test case creates the following stack scenario: 0xn0300 stack top 0xn0200 alt stack pointer top (when switching to alt stack) 0xn01ff alt stack end 0xn0100 alt stack start == stack pointer If the signal is sent the stack pointer is pointing to the base address of the alt stack and the kernel erroneously decides that it has already switched to the alternate stack because of the current check for "sp - sas_ss_sp < sas_ss_size" On parisc (stack grows up) the scenario would be: 0xn0200 stack pointer 0xn01ff alt stack end 0xn0100 alt stack start = alt stack pointer base (when switching to alt stack) 0xn0000 stack base This is handled correctly by the current implementation. [ tglx: Modified for archs which have the stack grow up (parisc) which would fail with the correct implementation for stack grows down. Added a check for sp >= current->sas_ss_sp which is strictly not necessary but makes the code symetric for both variants ] Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@redhat.com> Cc: Kyle McMartin <kyle@mcmartin.ca> LKML-Reference: <20091025143758.GA6653@Chamillionaire.breakpoint.cc> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-08USB: usb-serial: replace shutdown with disconnect, releaseAlan Stern
This is commit f9c99bb8b3a1ec81af68d484a551307326c2e933 back-ported to 2.6.27.39. This patch (as1254-2) splits up the shutdown method of usb_serial_driver into a disconnect and a release method. The problem is that the usb-serial core was calling shutdown during disconnect handling, but drivers didn't expect it to be called until after all the open file references had been closed. The result was an oops when the close method tried to use memory that had been deallocated by shutdown. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Rory Filer <rfiler@SierraWireless.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-09printk: robustify printkPeter Zijlstra
commit b845b517b5e3706a3729f6ea83b88ab85f0725b0 upstream. Avoid deadlocks against rq->lock and xtime_lock by deferring the klogd wakeup by polling from the timer tick. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-09irda: Add irda_skb_cb qdisc related paddingSamuel Ortiz
commit 69c30e1e7492192f882a3fc11888b320fde5206a upstream. We need to pad irda_skb_cb in order to keep it safe accross dev_queue_xmit() calls. This is some ugly and temporary hack triggered by recent qisc code changes. Even though it fixes bugzilla.kernel.org bug #11795, it will be replaced by a proper fix before 2.6.29 is released. Signed-off-by: Samuel Ortiz <samuel@sortiz.org> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-098250_pci: add IBM Saturn serial cardBenjamin Herrenschmidt
commit c68d2b1594548cda7f6dbac6a4d9d30a9b01558c upstream. The IBM Saturn serial card has only one port. Without that fixup, the kernel thinks it has two, which confuses userland setup and admin tools as well. [akpm@linux-foundation.org: fix pci-ids.h layout] Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Alan Cox <alan@linux.intel.com> Cc: Michael Reed <mreed10@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-12KVM: x86: Disallow hypercalls for guest callers in rings > 0 [CVE-2009-3290]Jan Kiszka
[ backport to 2.6.27 by Chuck Ebbert <cebbert@redhat.com> ] commit 07708c4af1346ab1521b26a202f438366b7bcffd upstream. So far unprivileged guest callers running in ring 3 can issue, e.g., MMU hypercalls. Normally, such callers cannot provide any hand-crafted MMU command structure as it has to be passed by its physical address, but they can still crash the guest kernel by passing random addresses. To close the hole, this patch considers hypercalls valid only if issued from guest ring 0. This may still be relaxed on a per-hypercall base in the future once required. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-12x86: Increase MIN_GAP to include randomized stackMichal Hocko
[ trivial backport to 2.6.27: Chuck Ebbert <cebbert@redhat.com> ] commit 80938332d8cf652f6b16e0788cf0ca136befe0b5 upstream. Currently we are not including randomized stack size when calculating mmap_base address in arch_pick_mmap_layout for topdown case. This might cause that mmap_base starts in the stack reserved area because stack is randomized by 1GB for 64b (8MB for 32b) and the minimum gap is 128MB. If the stack really grows down to mmap_base then we can get silent mmap region overwrite by the stack values. Let's include maximum stack randomization size into MIN_GAP which is used as the low bound for the gap in mmap. Signed-off-by: Michal Hocko <mhocko@suse.cz> LKML-Reference: <1252400515-6866-1-git-send-email-mhocko@suse.cz> Acked-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-24Short write in nfsd becomes a full write to the clientDavid Shaw
commit 31dec2538e45e9fff2007ea1f4c6bae9f78db724 upstream. Short write in nfsd becomes a full write to the client If a filesystem being written to via NFS returns a short write count (as opposed to an error) to nfsd, nfsd treats that as a success for the entire write, rather than the short count that actually succeeded. For example, given a 8192 byte write, if the underlying filesystem only writes 4096 bytes, nfsd will ack back to the nfs client that all 8192 bytes were written. The nfs client does have retry logic for short writes, but this is never called as the client is told the complete write succeeded. There are probably other ways it could happen, but in my case it happened with a fuse (filesystem in userspace) filesystem which can rather easily have a partial write. Here is a patch to properly return the short write count to the client. Signed-off-by: David Shaw <dshaw@jabberwocky.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-08SUNRPC: Fix tcp reconnectionTrond Myklebust
This fixes a problem that was reported as Red Hat Bugzilla entry number 485339, in which rpciod starts looping on the TCP connection code, rendering the NFS client unusable for 1/2 minute or so. It is basically a backport of commit f75e6745aa3084124ae1434fd7629853bdaf6798 (SUNRPC: Fix the problem of EADDRNOTAVAIL syslog floods on reconnect) Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-08parport: quickfix the proc registration bugAlan Cox
commit 05ad709d04799125ed85dd816fdb558258102172 upstream parport: quickfix the proc registration bug Ideally we should have a directory of drivers and a link to the 'active' driver. For now just show the first device which is effectively the existing semantics without a warning. This is an update on the original buggy patch that I then forgot to resubmit. Confusingly it was proposed by Red Hat, written by Etched Pixels fixed and submitted by Intel ... Resolves-Bug: http://bugzilla.kernel.org/show_bug.cgi?id=9749 Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-08KVM: Reduce stack usage in kvm_pv_mmu_op()Dave Hansen
(cherry picked from commit 6ad18fba05228fb1d47cdbc0339fe8b3fca1ca26) We're in a hot path. We can't use kmalloc() because it might impact performance. So, we just stick the buffer that we need into the kvm_vcpu_arch structure. This is used very often, so it is not really a waste. We also have to move the buffer structure's definition to the arch-specific x86 kvm header. Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-08-16NFS: Fix an O_DIRECT Oops...Trond Myklebust
commit 1ae88b2e446261c038f2c0c3150ffae142b227a2 upstream. We can't call nfs_readdata_release()/nfs_writedata_release() without first initialising and referencing args.context. Doing so inside nfs_direct_read_schedule_segment()/nfs_direct_write_schedule_segment() causes an Oops. We should rather be calling nfs_readdata_free()/nfs_writedata_free() in those cases. Looking at the O_DIRECT code, the "struct nfs_direct_req" is already referencing the nfs_open_context for us. Since the readdata and writedata structures carry a reference to that, we can simplify things by getting rid of the extra nfs_open_context references, so that we can replace all instances of nfs_readdata_release()/nfs_writedata_release(). Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>