kernel/include/linux, branch linux-3.5.y

mempolicy: fix a race in shared_policy_replace()

2012-10-12T20:47:21Z

commit b22d127a39ddd10d93deee3d96e643657ad53a49 upstream. shared_policy_replace() use of sp_alloc() is unsafe. 1) sp_node cannot be dereferenced if sp->lock is not held and 2) another thread can modify sp_node between spin_unlock for allocating a new sp node and next spin_lock. The bug was introduced before 2.6.12-rc2. Kosaki's original patch for this problem was to allocate an sp node and policy within shared_policy_replace and initialise it when the lock is reacquired. I was not keen on this approach because it partially duplicates sp_alloc(). As the paths were sp->lock is taken are not that performance critical this patch converts sp->lock to sp->mutex so it can sleep when calling sp_alloc(). [kosaki.motohiro@jp.fujitsu.com: Original patch] Signed-off-by: Mel Gorman Acked-by: KOSAKI Motohiro Reviewed-by: Christoph Lameter Cc: Josh Boyer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

xfrm_user: ensure user supplied esn replay window is valid

2012-10-12T20:47:10Z

commit ecd7918745234e423dd87fcc0c077da557909720 upstream. The current code fails to ensure that the netlink message actually contains as many bytes as the header indicates. If a user creates a new state or updates an existing one but does not supply the bytes for the whole ESN replay window, the kernel copies random heap bytes into the replay bitmap, the ones happen to follow the XFRMA_REPLAY_ESN_VAL netlink attribute. This leads to following issues: 1. The replay window has random bits set confusing the replay handling code later on. 2. A malicious user could use this flaw to leak up to ~3.5kB of heap memory when she has access to the XFRM netlink interface (requires CAP_NET_ADMIN). Known users of the ESN replay window are strongSwan and Steffen's iproute2 patch (). The latter uses the interface with a bitmap supplied while the former does not. strongSwan is therefore prone to run into issue 1. To fix both issues without breaking existing userland allow using the XFRMA_REPLAY_ESN_VAL netlink attribute with either an empty bitmap or a fully specified one. For the former case we initialize the in-kernel bitmap with zero, for the latter we copy the user supplied bitmap. For state updates the full bitmap must be supplied. To prevent overflows in the bitmap length calculation the maximum size of bmp_len is limited to 128 by this patch -- resulting in a maximum replay window of 4096 packets. This should be sufficient for all real life scenarios (RFC 4303 recommends a default replay window size of 64). Signed-off-by: Mathias Krause Cc: Steffen Klassert Cc: Martin Willi Cc: Ben Hutchings Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

serial: set correct baud_base for EXSYS EX-41092 Dual 16950

2012-10-07T15:35:53Z

commit 26e8220adb0aec43b7acafa0f1431760eee28522 upstream. Apparently the same card model has two IDs, so this patch complements the commit 39aced68d664291db3324d0fcf0985ab5626aac2 adding the missing one. Signed-off-by: Flavio Leitner Signed-off-by: Greg Kroah-Hartman

kthread_worker: reimplement flush_kthread_work() to allow freeing the work item being executed

2012-10-02T17:40:02Z

commit 46f3d976213452350f9d10b0c2780c2681f7075b upstream. kthread_worker provides minimalistic workqueue-like interface for users which need a dedicated worker thread (e.g. for realtime priority). It has basic queue, flush_work, flush_worker operations which mostly match the workqueue counterparts; however, due to the way flush_work() is implemented, it has a noticeable difference of not allowing work items to be freed while being executed. While the current users of kthread_worker are okay with the current behavior, the restriction does impede some valid use cases. Also, removing this difference isn't difficult and actually makes the code easier to understand. This patch reimplements flush_kthread_work() such that it uses a flush_work item instead of queue/done sequence numbers. Signed-off-by: Tejun Heo Cc: Colin Cross Signed-off-by: Greg Kroah-Hartman

time: Move ktime_t overflow checking into timespec_valid_strict

2012-10-02T17:39:48Z

commit cee58483cf56e0ba355fdd97ff5e8925329aa936 upstream. Andreas Bombe reported that the added ktime_t overflow checking added to timespec_valid in commit 4e8b14526ca7 ("time: Improve sanity checking of timekeeping inputs") was causing problems with X.org because it caused timeouts larger then KTIME_T to be invalid. Previously, these large timeouts would be clamped to KTIME_MAX and would never expire, which is valid. This patch splits the ktime_t overflow checking into a new timespec_valid_strict function, and converts the timekeeping codes internal checking to use this more strict function. Reported-and-tested-by: Andreas Bombe Cc: Zhouping Liu Cc: Ingo Molnar Cc: Prarit Bhargava Cc: Thomas Gleixner Signed-off-by: John Stultz Signed-off-by: Linus Torvalds Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman

time: Improve sanity checking of timekeeping inputs

2012-10-02T17:39:48Z

commit 4e8b14526ca7fb046a81c94002c1c43b6fdf0e9b upstream. Unexpected behavior could occur if the time is set to a value large enough to overflow a 64bit ktime_t (which is something larger then the year 2262). Also unexpected behavior could occur if large negative offsets are injected via adjtimex. So this patch improves the sanity check timekeeping inputs by improving the timespec_valid() check, and then makes better use of timespec_valid() to make sure we don't set the time to an invalid negative value or one that overflows ktime_t. Note: This does not protect from setting the time close to overflowing ktime_t and then letting natural accumulation cause the overflow. Reported-by: CAI Qian Reported-by: Sasha Levin Signed-off-by: John Stultz Cc: Peter Zijlstra Cc: Prarit Bhargava Cc: Zhouping Liu Cc: Ingo Molnar Link: http://lkml.kernel.org/r/1344454580-17031-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman

sched: Fix race in task_group()

2012-10-02T17:39:47Z

commit 8323f26ce3425460769605a6aece7a174edaa7d1 upstream. Stefan reported a crash on a kernel before a3e5d1091c1 ("sched: Don't call task_group() too many times in set_task_rq()"), he found the reason to be that the multiple task_group() invocations in set_task_rq() returned different values. Looking at all that I found a lack of serialization and plain wrong comments. The below tries to fix it using an extra pointer which is updated under the appropriate scheduler locks. Its not pretty, but I can't really see another way given how all the cgroup stuff works. Reported-and-tested-by: Stefan Bader Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1340364965.18025.71.camel@twins Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

NFS: Fix the initialisation of the readdir 'cookieverf' array

2012-10-02T17:39:27Z

commit c3f52af3e03013db5237e339c817beaae5ec9e3a upstream. When the NFS_COOKIEVERF helper macro was converted into a static inline function in commit 99fadcd764 (nfs: convert NFS_*(inode) helpers to static inline), we broke the initialisation of the readdir cookies, since that depended on doing a memset with an argument of 'sizeof(NFS_COOKIEVERF(inode))' which therefore changed from sizeof(be32 cookieverf[2]) to sizeof(be32 *). At this point, NFS_COOKIEVERF seems to be more of an obfuscation than a helper, so the best thing would be to just get rid of it. Also see: https://bugzilla.kernel.org/show_bug.cgi?id=46881 Reported-by: Andi Kleen Reported-by: David Binderman Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

perf/x86/ibs: Check syscall attribute flags

2012-10-02T17:39:25Z

commit bad9ac2d7f878a31cf1ae8c1ee3768077d222bcb upstream. Current implementation simply ignores attribute flags. Thus, there is no notification to userland of unsupported features. Check syscall's attribute flags to let userland know if a feature is supported by the kernel. This is also needed to distinguish between future kernels what might support a feature. Signed-off-by: Robert Richter Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20120910093018.GO8285@erda.amd.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

c/r: prctl: fix build error for no-MMU case

2012-10-02T17:39:24Z

commit be8cfc4af15cf611dfeb66a1fb5df43d5f1e280a upstream. Commit 1ad75b9e1628 ("c/r: prctl: add minimal address test to PR_SET_MM") added some address checking to prctl_set_mm() used by checkpoint-restore. This causes a build error for no-MMU systems: kernel/sys.c: In function 'prctl_set_mm': kernel/sys.c:1868:34: error: 'mmap_min_addr' undeclared (first use in this function) The test for mmap_min_addr doesn't make a lot of sense for no-MMU code as noted in commit 6e1415467614 ("NOMMU: Optimise away the {dac_,}mmap_min_addr tests"). This patch defines mmap_min_addr as 0UL in the no-MMU case so that the compiler will optimize away tests for "addr < mmap_min_addr". Signed-off-by: Mark Salter Reviewed-by: Cyrill Gorcunov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman