kernel/git/stable/linux.git/arch/s390, branch linux-3.5.y

oprofile, s390: Fix uninitialized memory access when writing to oprofilefs

2012-10-02T17:39:09+00:00

commit 81ff3478d9ba7f0b48b0abef740e542fd83adf79 upstream. If oprofilefs_ulong_from_user() is called with count equals zero, *val remains unchanged. Depending on the implementation it might be uninitialized. Fixing users of oprofilefs_ulong_ from_user(). We missed these s390 changes with: 913050b oprofile: Fix uninitialized memory access when writing to writing to oprofilefs Signed-off-by: Robert Richter Signed-off-by: Greg Kroah-Hartman

s390/compat: fix mmap compat system calls

2012-08-26T02:31:38+00:00

commit e85871218513c54f7dfdb6009043cb638f2fecbe upstream. The native 31 bit and the compat behaviour for the mmap system calls differ: In native 31 bit mode the passed in address for the mmap system call will be unmodified passed to sys_mmap_pgoff(). In compat mode however the passed in address will be modified with compat_ptr() which masks out the most significant bit. The result is that in native 31 bit mode each mmap request (with MAP_FIXED) will fail where the most significat bit is set, while in compat mode it may succeed. This odd behaviour was introduced with d3815898 "[S390] mmap: add missing compat_ptr conversion to both mmap compat syscalls". To restore a consistent behaviour accross native and compat mode this patch functionally reverts the above mentioned commit. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman

s390/compat: fix compat wrappers for process_vm system calls

2012-08-26T02:31:38+00:00

commit 82aabdb6f1eb61e0034ec23901480f5dd23db7c4 upstream. The compat wrappers incorrectly called the non compat versions of the system process_vm system calls. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman

s390/mm: fix fault handling for page table walk case

2012-08-09T15:22:53+00:00

commit 008c2e8f247f0a8db1e8e26139da12f3a3abcda0 upstream. Make sure the kernel does not incorrectly create a SIGBUS signal during user space accesses: For user space accesses in the switched addressing mode case the kernel may walk page tables and access user address space via the kernel mapping. If a page table entry is invalid the function __handle_fault() gets called in order to emulate a page fault and trigger all the usual actions like paging in a missing page etc. by calling handle_mm_fault(). If handle_mm_fault() returns with an error fixup handling is necessary. For the switched addressing mode case all errors need to be mapped to -EFAULT, so that the calling uaccess function can return -EFAULT to user space. Unfortunately the __handle_fault() incorrectly calls do_sigbus() if VM_FAULT_SIGBUS is set. This however should only happen if a page fault was triggered by a user space instruction. For kernel mode uaccesses the correct action is to only return -EFAULT. So user space may incorrectly see SIGBUS signals because of this bug. For current machines this would only be possible for the switched addressing mode case in conjunction with futex operations. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman

s390/mm: downgrade page table after fork of a 31 bit process

2012-08-09T15:22:53+00:00

commit 0f6f281b731d20bfe75c13f85d33f3f05b440222 upstream. The downgrade of the 4 level page table created by init_new_context is currently done only in start_thread31. If a 31 bit process forks the new mm uses a 4 level page table, including the task size of 2<<42 that goes along with it. This is incorrect as now a 31 bit process can map memory beyond 2GB. Define arch_dup_mmap to do the downgrade after fork. Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman

s390/idle: fix sequence handling vs cpu hotplug

2012-08-09T15:22:53+00:00

commit 0008204ffe85d23382d6fd0f971f3f0fbe70bae2 upstream. The s390 idle accounting code uses a sequence counter which gets used when the per cpu idle statistics get updated and read. One assumption on read access is that only when the sequence counter is even and did not change while reading all values the result is valid. On cpu hotplug however the per cpu data structure gets initialized via a cpu hotplug notifier on CPU_ONLINE. CPU_ONLINE however is too late, since the onlined cpu is already running and might access the per cpu data. Worst case is that the data structure gets initialized while an idle thread is updating its idle statistics. This will result in an uneven sequence counter after an update. As a result user space tools like top, which access /proc/stat in order to get idle stats, will busy loop waiting for the sequence counter to become even again, which will never happen until the queried cpu will update its idle statistics again. And even then the sequence counter will only have an even value for a couple of cpu cycles. Fix this by moving the initialization of the per cpu idle statistics to cpu_init(). I prefer that solution in favor of changing the notifier to CPU_UP_PREPARE, which would be a different solution to the problem. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

2012-06-01T18:53:44+00:00

Pull third pile of signal handling patches from Al Viro: "This time it's mostly helpers and conversions to them; there's a lot of stuff remaining in the tree, but that'll either go in -rc2 (isolated bug fixes, ideally via arch maintainers' trees) or will sit there until the next cycle." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: x86: get rid of calling do_notify_resume() when returning to kernel mode blackfin: check __get_user() return value whack-a-mole with TIF_FREEZE FRV: Optimise the system call exit path in entry.S [ver #2] FRV: Shrink TIF_WORK_MASK [ver #2] FRV: Prevent syscall exit tracing and notify_resume at end of kernel exceptions new helper: signal_delivered() powerpc: get rid of restore_sigmask() most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set set_restore_sigmask() is never called without SIGPENDING (and never should be) TIF_RESTORE_SIGMASK can be set only when TIF_SIGPENDING is set don't call try_to_freeze() from do_signal() pull clearing RESTORE_SIGMASK into block_sigmask() sh64: failure to build sigframe != signal without handler openrisc: tracehook_signal_handler() is supposed to be called on success new helper: sigmask_to_save() new helper: restore_saved_sigmask() new helpers: {clear,test,test_and_clear}_restore_sigmask() HAVE_RESTORE_SIGMASK is defined on all architectures now

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2012-06-01T17:34:35+00:00

Pull vfs changes from Al Viro. "A lot of misc stuff. The obvious groups: * Miklos' atomic_open series; kills the damn abuse of ->d_revalidate() by NFS, which was the major stumbling block for all work in that area. * ripping security_file_mmap() and dealing with deadlocks in the area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in general. * ->encode_fh() switched to saner API; insane fake dentry in mm/cleancache.c gone. * assorted annotations in fs (endianness, __user) * parts of Artem's ->s_dirty work (jff2 and reiserfs parts) * ->update_time() work from Josef. * other bits and pieces all over the place. Normally it would've been in two or three pull requests, but signal.git stuff had eaten a lot of time during this cycle ;-/" Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the 'truncate_range' inode method was removed by the VM changes, the VFS update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due to sparse fix added twice, with other changes nearby). * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits) nfs: don't open in ->d_revalidate vfs: retry last component if opening stale dentry vfs: nameidata_to_filp(): don't throw away file on error vfs: nameidata_to_filp(): inline __dentry_open() vfs: do_dentry_open(): don't put filp vfs: split __dentry_open() vfs: do_last() common post lookup vfs: do_last(): add audit_inode before open vfs: do_last(): only return EISDIR for O_CREAT vfs: do_last(): check LOOKUP_DIRECTORY vfs: do_last(): make ENOENT exit RCU safe vfs: make follow_link check RCU safe vfs: do_last(): use inode variable vfs: do_last(): inline walk_component() vfs: do_last(): make exit RCU safe vfs: split do_lookup() Btrfs: move over to use ->update_time fs: introduce inode operation ->update_time reiserfs: get rid of resierfs_sync_super reiserfs: mark the superblock as dirty a bit later ...

new helper: signal_delivered()

2012-06-01T16:58:52+00:00

Does block_sigmask() + tracehook_signal_handler(); called when sigframe has been successfully built. All architectures converted to it; block_sigmask() itself is gone now (merged into this one). I'm still not too happy with the signature, but that's a separate story (IMO we need a structure that would contain signal number + siginfo + k_sigaction, so that get_signal_to_deliver() would fill one, signal_delivered(), handle_signal() and probably setup...frame() - take one). Signed-off-by: Al Viro

most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set

2012-06-01T16:58:51+00:00

Only 3 out of 63 do not. Renamed the current variant to __set_current_blocked(), added set_current_blocked() that will exclude unblockable signals, switched open-coded instances to it. Signed-off-by: Al Viro