user/sven/linux.git/ipc, branch v4.18.5

ipc/shm.c add ->pagesize function to shm_vm_ops

2018-08-02T23:03:40Z

Commit 05ea88608d4e ("mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct") adds a new ->pagesize() function to hugetlb_vm_ops, intended to cover all hugetlbfs backed files. With System V shared memory model, if "huge page" is specified, the "shared memory" is backed by hugetlbfs files, but the mappings initiated via shmget/shmat have their original vm_ops overwritten with shm_vm_ops, so we need to add a ->pagesize function to shm_vm_ops. Otherwise, vma_kernel_pagesize() returns PAGE_SIZE given a hugetlbfs backed vma, result in below BUG: fs/hugetlbfs/inode.c 443 if (unlikely(page_mapped(page))) { 444 BUG_ON(truncate_op); resulting in hugetlbfs: oracle (4592): Using mlock ulimits for SHM_HUGETLB is deprecated ------------[ cut here ]------------ kernel BUG at fs/hugetlbfs/inode.c:444! Modules linked in: nfsv3 rpcsec_gss_krb5 nfsv4 ... CPU: 35 PID: 5583 Comm: oracle_5583_sbt Not tainted 4.14.35-1829.el7uek.x86_64 #2 RIP: 0010:remove_inode_hugepages+0x3db/0x3e2 .... Call Trace: hugetlbfs_evict_inode+0x1e/0x3e evict+0xdb/0x1af iput+0x1a2/0x1f7 dentry_unlink_inode+0xc6/0xf0 __dentry_kill+0xd8/0x18d dput+0x1b5/0x1ed __fput+0x18b/0x216 ____fput+0xe/0x10 task_work_run+0x90/0xa7 exit_to_usermode_loop+0xdd/0x116 do_syscall_64+0x187/0x1ae entry_SYSCALL_64_after_hwframe+0x150/0x0 [jane.chu@oracle.com: relocate comment] Link: http://lkml.kernel.org/r/20180731044831.26036-1-jane.chu@oracle.com Link: http://lkml.kernel.org/r/20180727211727.5020-1-jane.chu@oracle.com Fixes: 05ea88608d4e13 ("mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct") Signed-off-by: Jane Chu Suggested-by: Mike Kravetz Reviewed-by: Mike Kravetz Acked-by: Davidlohr Bueso Acked-by: Michal Hocko Cc: Dan Williams Cc: Jan Kara Cc: Jérôme Glisse Cc: Manfred Spraul Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: prevent queue.status tearing in semop

2018-07-27T02:38:03Z

In order for load/store tearing prevention to work, _all_ accesses to the variable in question need to be done around READ and WRITE_ONCE() macros. Ensure everyone does so for q->status variable for semtimedop(). Link: http://lkml.kernel.org/r/20180717052654.676-1-dave@stgolabs.net Signed-off-by: Davidlohr Bueso Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: use new return type vm_fault_t

2018-06-14T22:55:25Z

Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Commit 1c8f422059ae ("mm: change return type to vm_fault_t") Link: http://lkml.kernel.org/r/20180425043413.GA21467@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder Reviewed-by: Matthew Wilcox Reviewed-by: Andrew Morton Acked-by: Davidlohr Bueso Cc: Manfred Spraul Cc: Eric W. Biederman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sysvipc/sem: mitigate semnum index against spectre v1

2018-06-14T22:55:25Z

Both smatch and coverity are reporting potential issues with spectre variant 1 with the 'semnum' index within the sma->sems array, ie: ipc/sem.c:388 sem_lock() warn: potential spectre issue 'sma->sems' ipc/sem.c:641 perform_atomic_semop_slow() warn: potential spectre issue 'sma->sems' ipc/sem.c:721 perform_atomic_semop() warn: potential spectre issue 'sma->sems' Avoid any possible speculation by using array_index_nospec() thus ensuring the semnum value is bounded to [0, sma->sem_nsems). With the exception of sem_lock() all of these are slowpaths. Link: http://lkml.kernel.org/r/20180423171131.njs4rfm2yzyeg6do@linux-n805 Signed-off-by: Davidlohr Bueso Reported-by: Dan Carpenter Cc: Peter Zijlstra Cc: "Gustavo A. R. Silva" Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

treewide: kvmalloc() -> kvmalloc_array()

2018-06-12T23:19:22Z

The kvmalloc() function has a 2-factor argument form, kvmalloc_array(). This patch replaces cases of: kvmalloc(a * b, gfp) with: kvmalloc_array(a * b, gfp) as well as handling cases of: kvmalloc(a * b * c, gfp) with: kvmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kvmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kvmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kvmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kvmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kvmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kvmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kvmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kvmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kvmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kvmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kvmalloc( - sizeof(char) * COUNT + COUNT , ...) | kvmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kvmalloc + kvmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kvmalloc + kvmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kvmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kvmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kvmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kvmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kvmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kvmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kvmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kvmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kvmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kvmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kvmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kvmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kvmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kvmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kvmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kvmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kvmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kvmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kvmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kvmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kvmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kvmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kvmalloc(C1 * C2 * C3, ...) | kvmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kvmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kvmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kvmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kvmalloc(sizeof(THING) * C2, ...) | kvmalloc(sizeof(TYPE) * C2, ...) | kvmalloc(C1 * C2 * C3, ...) | kvmalloc(C1 * C2, ...) | - kvmalloc + kvmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kvmalloc + kvmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kvmalloc + kvmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kvmalloc + kvmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kvmalloc + kvmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook

Merge branch 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-06-05T04:02:18Z

Pull time/Y2038 updates from Thomas Gleixner: - Consolidate SySV IPC UAPI headers - Convert SySV IPC to the new COMPAT_32BIT_TIME mechanism - Cleanup the core interfaces and standardize on the ktime_get_* naming convention. - Convert the X86 platform ops to timespec64 - Remove the ugly temporary timespec64 hack * 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86: Convert x86_platform_ops to timespec64 timekeeping: Add more coarse clocktai/boottime interfaces timekeeping: Add ktime_get_coarse_with_offset timekeeping: Standardize on ktime_get_*() naming timekeeping: Clean up ktime_get_real_ts64 timekeeping: Remove timespec64 hack y2038: ipc: Redirect ipc(SEMTIMEDOP, ...) to compat_ksys_semtimedop y2038: ipc: Enable COMPAT_32BIT_TIME y2038: ipc: Use __kernel_timespec y2038: ipc: Report long times to user space y2038: ipc: Use ktime_get_real_seconds consistently y2038: xtensa: Extend sysvipc data structures y2038: powerpc: Extend sysvipc data structures y2038: sparc: Extend sysvipc data structures y2038: parisc: Extend sysvipc data structures y2038: mips: Extend sysvipc data structures y2038: arm64: Extend sysvipc compat data structures y2038: s390: Remove unneeded ipc uapi header files y2038: ia64: Remove unneeded ipc uapi header files y2038: alpha: Remove unneeded ipc uapi header files ...

ipc/shm: fix shmat() nil address after round-down when remapping

2018-05-26T01:12:11Z

shmat()'s SHM_REMAP option forbids passing a nil address for; this is in fact the very first thing we check for. Andrea reported that for SHM_RND|SHM_REMAP cases we can end up bypassing the initial addr check, but we need to check again if the address was rounded down to nil. As of this patch, such cases will return -EINVAL. Link: http://lkml.kernel.org/r/20180503204934.kk63josdu6u53fbd@linux-n805 Signed-off-by: Davidlohr Bueso Reported-by: Andrea Arcangeli Cc: Joe Lawrence Cc: Manfred Spraul Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Revert "ipc/shm: Fix shmat mmap nil-page protection"

2018-05-26T01:12:11Z

Patch series "ipc/shm: shmat() fixes around nil-page". These patches fix two issues reported[1] a while back by Joe and Andrea around how shmat(2) behaves with nil-page. The first reverts a commit that it was incorrectly thought that mapping nil-page (address=0) was a no no with MAP_FIXED. This is not the case, with the exception of SHM_REMAP; which is address in the second patch. I chose two patches because it is easier to backport and it explicitly reverts bogus behaviour. Both patches ought to be in -stable and ltp testcases need updated (the added testcase around the cve can be modified to just test for SHM_RND|SHM_REMAP). [1] lkml.kernel.org/r/20180430172152.nfa564pvgpk3ut7p@linux-n805 This patch (of 2): Commit 95e91b831f87 ("ipc/shm: Fix shmat mmap nil-page protection") worked on the idea that we should not be mapping as root addr=0 and MAP_FIXED. However, it was reported that this scenario is in fact valid, thus making the patch both bogus and breaks userspace as well. For example X11's libint10.so relies on shmat(1, SHM_RND) for lowmem initialization[1]. [1] https://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/os-support/linux/int10/linux.c#n347 Link: http://lkml.kernel.org/r/20180503203243.15045-2-dave@stgolabs.net Fixes: 95e91b831f87 ("ipc/shm: Fix shmat mmap nil-page protection") Signed-off-by: Davidlohr Bueso Reported-by: Joe Lawrence Reported-by: Andrea Arcangeli Cc: Manfred Spraul Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

y2038: ipc: Redirect ipc(SEMTIMEDOP, ...) to compat_ksys_semtimedop

2018-04-20T14:20:30Z

32-bit architectures implementing 64BIT_TIME and COMPAT_32BIT_TIME need to have the traditional semtimedop() behavior with 32-bit timestamps for sys_ipc() by calling compat_ksys_semtimedop(), while those that are not yet converted need to keep using ksys_semtimedop() like 64-bit architectures do. Note that I chose to not implement a new SEMTIMEDOP64 function that corresponds to the new sys_semtimedop() with 64-bit timeouts. The reason here is that sys_ipc() should no longer be used for new system calls, and libc should just call the semtimedop syscall directly. One open question remain to whether we want to completely avoid the sys_ipc() system call for architectures that do not yet have all the individual calls as they get converted to 64-bit time_t. Doing that would require adding several extra system calls on m68k, mips, powerpc, s390, sh, sparc, and x86-32. Signed-off-by: Arnd Bergmann

y2038: ipc: Enable COMPAT_32BIT_TIME

2018-04-20T14:20:27Z

Three ipc syscalls (mq_timedsend, mq_timedreceive and and semtimedop) take a timespec argument. After we move 32-bit architectures over to useing 64-bit time_t based syscalls, we need seperate entry points for the old 32-bit based interfaces. This changes the #ifdef guards for the existing 32-bit compat syscalls to check for CONFIG_COMPAT_32BIT_TIME instead, which will then be enabled on all existing 32-bit architectures. Signed-off-by: Arnd Bergmann