user/sven/linux.git/arch/alpha/kernel, branch v4.9.220

sys: don't hold uts_sem while accessing userspace memory

2018-09-09T18:01:24Z

commit 42a0cc3478584d4d63f68f2f5af021ddbea771fa upstream. Holding uts_sem as a writer while accessing userspace memory allows a namespace admin to stall all processes that attempt to take uts_sem. Instead, move data through stack buffers and don't access userspace memory while uts_sem is held. Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jann Horn Signed-off-by: Eric W. Biederman Signed-off-by: Greg Kroah-Hartman

osf_getdomainname(): use copy_to_user()

2018-09-09T18:01:24Z

commit 9ba3eb5103cf56f0daaf07de4507df76e7813ed7 upstream. Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

vgacon: Set VGA struct resource types

2018-03-24T10:00:25Z

[ Upstream commit c82084117f79bcae085e40da526253736a247120 ] Set the resource type when we reserve VGA-related I/O port resources. The resource code doesn't actually look at the type, so it inserts resources without a type in the tree correctly even without this change. But if we ever print a resource without a type, it looks like this: vga+ [??? 0x000003c0-0x000003df flags 0x0] Setting the type means it will be printed correctly as: vga+ [io 0x000003c0-0x000003df] Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

alpha: fix formating of stack content

2018-02-17T12:21:19Z

commit 4b01abdb32fc36abe877503bfbd33019159fad71 upstream. Since version 4.9, the kernel automatically breaks printk calls into multiple newlines unless pr_cont is used. Fix the alpha stacktrace code, so that it prints stack trace in four columns, as it was initially intended. Signed-off-by: Mikulas Patocka Signed-off-by: Matt Turner Signed-off-by: Greg Kroah-Hartman

alpha: fix reboot on Avanti platform

2018-02-17T12:21:19Z

commit 55fc633c41a08ce9244ff5f528f420b16b1e04d6 upstream. We need to define NEED_SRM_SAVE_RESTORE on the Avanti, otherwise we get machine check exception when attempting to reboot the machine. Signed-off-by: Mikulas Patocka Signed-off-by: Matt Turner Signed-off-by: Greg Kroah-Hartman

alpha: fix crash if pthread_create races with signal delivery

2018-02-17T12:21:19Z

commit 21ffceda1c8b3807615c40d440d7815e0c85d366 upstream. On alpha, a process will crash if it attempts to start a thread and a signal is delivered at the same time. The crash can be reproduced with this program: https://cygwin.com/ml/cygwin/2014-11/msg00473.html The reason for the crash is this: * we call the clone syscall * we go to the function copy_process * copy process calls copy_thread_tls, it is a wrapper around copy_thread * copy_thread sets the tls pointer: childti->pcb.unique = regs->r20 * copy_thread sets regs->r20 to zero * we go back to copy_process * copy process checks "if (signal_pending(current))" and returns -ERESTARTNOINTR * the clone syscall is restarted, but this time, regs->r20 is zero, so the new thread is created with zero tls pointer * the new thread crashes in start_thread when attempting to access tls The comment in the code says that setting the register r20 is some compatibility with OSF/1. But OSF/1 doesn't use the CLONE_SETTLS flag, so we don't have to zero r20 if CLONE_SETTLS is set. This patch fixes the bug by zeroing regs->r20 only if CLONE_SETTLS is not set. Signed-off-by: Mikulas Patocka Signed-off-by: Matt Turner Signed-off-by: Greg Kroah-Hartman

osf_wait4(): fix infoleak

2017-05-25T13:44:47Z

commit a8c39544a6eb2093c04afd5005b6192bd0e880c6 upstream. failing sys_wait4() won't fill struct rusage... Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

ptrace: Don't allow accessing an undumpable mm

2017-01-06T09:40:13Z

commit 84d77d3f06e7e8dea057d10e8ec77ad71f721be3 upstream. It is the reasonable expectation that if an executable file is not readable there will be no way for a user without special privileges to read the file. This is enforced in ptrace_attach but if ptrace is already attached before exec there is no enforcement for read-only executables. As the only way to read such an mm is through access_process_vm spin a variant called ptrace_access_vm that will fail if the target process is not being ptraced by the current process, or the current process did not have sufficient privileges when ptracing began to read the target processes mm. In the ptrace implementations replace access_process_vm by ptrace_access_vm. There remain several ptrace sites that still use access_process_vm as they are reading the target executables instructions (for kernel consumption) or register stacks. As such it does not appear necessary to add a permission check to those calls. This bug has always existed in Linux. Fixes: v1.0 Reported-by: Andy Lutomirski Signed-off-by: "Eric W. Biederman" Signed-off-by: Greg Kroah-Hartman

Merge branch 'gup_flag-cleanups'

2016-10-19T15:39:47Z

Merge the gup_flags cleanups from Lorenzo Stoakes: "This patch series adjusts functions in the get_user_pages* family such that desired FOLL_* flags are passed as an argument rather than implied by flags. The purpose of this change is to make the use of FOLL_FORCE explicit so it is easier to grep for and clearer to callers that this flag is being used. The use of FOLL_FORCE is an issue as it overrides missing VM_READ/VM_WRITE flags for the VMA whose pages we are reading from/writing to, which can result in surprising behaviour. The patch series came out of the discussion around commit 38e088546522 ("mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing"), which addressed a BUG_ON() being triggered when a page was faulted in with PROT_NONE set but having been overridden by FOLL_FORCE. do_numa_page() was run on the assumption the page _must_ be one marked for NUMA node migration as an actual PROT_NONE page would have been dealt with prior to this code path, however FOLL_FORCE introduced a situation where this assumption did not hold. See https://marc.info/?l=linux-mm&m=147585445805166 for the patch proposal" Additionally, there's a fix for an ancient bug related to FOLL_FORCE and FOLL_WRITE by me. [ This branch was rebased recently to add a few more acked-by's and reviewed-by's ] * gup_flag-cleanups: mm: replace access_process_vm() write parameter with gup_flags mm: replace access_remote_vm() write parameter with gup_flags mm: replace __access_remote_vm() write parameter with gup_flags mm: replace get_user_pages_remote() write/force parameters with gup_flags mm: replace get_user_pages() write/force parameters with gup_flags mm: replace get_vaddr_frames() write/force parameters with gup_flags mm: replace get_user_pages_locked() write/force parameters with gup_flags mm: replace get_user_pages_unlocked() write/force parameters with gup_flags mm: remove write/force parameters from __get_user_pages_unlocked() mm: remove write/force parameters from __get_user_pages_locked() mm: remove gup_flags FOLL_WRITE games from __get_user_pages()

mm: replace access_process_vm() write parameter with gup_flags

2016-10-19T15:31:25Z

This removes the 'write' argument from access_process_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes Acked-by: Jesper Nilsson Acked-by: Michal Hocko Acked-by: Michael Ellerman Signed-off-by: Linus Torvalds