kernel/linux.git/fs/proc, branch linux-5.11.y

fs/proc/generic.c: fix incorrect pde_is_permanent check

2021-05-19T08:29:47+00:00

[ Upstream commit f4bf74d82915708208bc9d0c9bd3f769f56bfbec ] Currently the pde_is_permanent() check is being run on root multiple times rather than on the next proc directory entry. This looks like a copy-paste error. Fix this by replacing root with next. Addresses-Coverity: ("Copy-paste error") Link: https://lkml.kernel.org/r/20210318122633.14222-1-colin.king@canonical.com Fixes: d919b33dafb3 ("proc: faster open/read/close with "permanent" files") Signed-off-by: Colin Ian King Acked-by: Christian Brauner Reviewed-by: Alexey Dobriyan Cc: Greg Kroah-Hartman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

seccomp: Fix CONFIG tests for Seccomp_filters

2021-05-14T08:49:54+00:00

[ Upstream commit 64bdc0244054f7d4bb621c8b4455e292f4e421bc ] Strictly speaking, seccomp filters are only used when CONFIG_SECCOMP_FILTER. This patch fixes the condition to enable "Seccomp_filters" in /proc/$pid/status. Signed-off-by: Kenta Tada Fixes: c818c03b661c ("seccomp: Report number of loaded filters in /proc/$pid/status") Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/OSBPR01MB26772D245E2CF4F26B76A989F5669@OSBPR01MB2677.jpnprd01.prod.outlook.com Signed-off-by: Sasha Levin

proc: don't allow async path resolution of /proc/thread-self components

2021-03-04T11:15:38+00:00

commit 0d4370cfe36b7f1719123b621a4ec4d9c7a25f89 upstream. If this is attempted by an io-wq kthread, then return -EOPNOTSUPP as we don't currently support that. Once we can get task_pid_ptr() doing the right thing, then this can go away again. Use PF_IO_WORKER for this to speciically target the io_uring workers. Modify the /proc/self/ check to use PF_IO_WORKER as well. Cc: stable@vger.kernel.org Fixes: 8d4c3e76e3be ("proc: don't allow async path resolution of /proc/self components") Reported-by: Eric W. Biederman Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

proc: use kvzalloc for our kernel buffer

2021-03-04T11:15:16+00:00

[ Upstream commit 4508943794efdd94171549c0bd52810e2f4ad9fe ] Since sysctl: pass kernel pointers to ->proc_handler we have been pre-allocating a buffer to copy the data from the proc handlers into, and then copying that to userspace. The problem is this just blindly kzalloc()'s the buffer size passed in from the read, which in the case of our 'cat' binary was 64kib. Order-4 allocations are not awesome, and since we can potentially allocate up to our maximum order, so use kvzalloc for these buffers. [willy@infradead.org: changelog tweaks] Link: https://lkml.kernel.org/r/6345270a2c1160b89dd5e6715461f388176899d1.1612972413.git.josef@toxicpanda.com Fixes: 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler") Signed-off-by: Josef Bacik Reviewed-by: Christoph Hellwig Acked-by: Vlastimil Babka Cc: Al Viro Cc: Alexey Dobriyan CC: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

mm: proc: Invalidate TLB after clearing soft-dirty page state

2021-03-04T11:14:19+00:00

[ Upstream commit 912efa17e5121693dfbadae29768f4144a3f9e62 ] Since commit 0758cd830494 ("asm-generic/tlb: avoid potential double flush"), TLB invalidation is elided in tlb_finish_mmu() if no entries were batched via the tlb_remove_*() functions. Consequently, the page-table modifications performed by clear_refs_write() in response to a write to /proc//clear_refs do not perform TLB invalidation. Although this is fine when simply aging the ptes, in the case of clearing the "soft-dirty" state we can end up with entries where pte_write() is false, yet a writable mapping remains in the TLB. Fix this by avoiding the mmu_gather API altogether: managing both the 'tlb_flush_pending' flag on the 'mm_struct' and explicit TLB invalidation for the sort-dirty path, much like mprotect() does already. Fixes: 0758cd830494 ("asm-generic/tlb: avoid potential double flush”) Signed-off-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Yu Zhao Acked-by: Peter Zijlstra (Intel) Acked-by: Linus Torvalds Link: https://lkml.kernel.org/r/20210127235347.1402-2-will@kernel.org Signed-off-by: Sasha Levin

proc_sysctl: fix oops caused by incorrect command parameters

2021-01-24T18:34:53+00:00

The process_sysctl_arg() does not check whether val is empty before invoking strlen(val). If the command line parameter () is incorrectly configured and val is empty, oops is triggered. For example: "hung_task_panic=1" is incorrectly written as "hung_task_panic", oops is triggered. The call stack is as follows: Kernel command line: .... hung_task_panic ...... Call trace: __pi_strlen+0x10/0x98 parse_args+0x278/0x344 do_sysctl_args+0x8c/0xfc kernel_init+0x5c/0xf4 ret_from_fork+0x10/0x30 To fix it, check whether "val" is empty when "phram" is a sysctl field. Error codes are returned in the failure branch, and error logs are generated by parse_args(). Link: https://lkml.kernel.org/r/20210118133029.28580-1-nixiaoming@huawei.com Fixes: 3db978d480e2843 ("kernel/sysctl: support setting sysctl parameters from kernel command line") Signed-off-by: Xiaoming Ni Acked-by: Vlastimil Babka Cc: Luis Chamberlain Cc: Kees Cook Cc: Iurii Zaikin Cc: Alexey Dobriyan Cc: Michal Hocko Cc: Masami Hiramatsu Cc: Heiner Kallweit Cc: Randy Dunlap Cc: [5.8+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: don't play games with pinned pages in clear_page_refs

2021-01-16T18:51:26+00:00

Turning a pinned page read-only breaks the pinning after COW. Don't do it. The whole "track page soft dirty" state doesn't work with pinned pages anyway, since the page might be dirtied by the pinning entity without ever being noticed in the page tables. Signed-off-by: Linus Torvalds

mm: fix clear_refs_write locking

2021-01-16T18:46:39+00:00

Turning page table entries read-only requires the mmap_sem held for writing. So stop doing the odd games with turning things from read locks to write locks and back. Just get the write lock. Signed-off-by: Linus Torvalds

Merge tag 'seccomp-v5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2020-12-16T19:30:10+00:00

Pull seccomp updates from Kees Cook: "The major change here is finally gaining seccomp constant-action bitmaps, which internally reduces the seccomp overhead for many real-world syscall filters to O(1), as discussed at Plumbers this year. - Improve seccomp performance via constant-action bitmaps (YiFei Zhu & Kees Cook) - Fix bogus __user annotations (Jann Horn) - Add missed CONFIG for improved selftest coverage (Mickaël Salaün)" * tag 'seccomp-v5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: selftests/seccomp: Update kernel config seccomp: Remove bogus __user annotations seccomp/cache: Report cache data through /proc/pid/seccomp_cache xtensa: Enable seccomp architecture tracking sh: Enable seccomp architecture tracking s390: Enable seccomp architecture tracking riscv: Enable seccomp architecture tracking powerpc: Enable seccomp architecture tracking parisc: Enable seccomp architecture tracking csky: Enable seccomp architecture tracking arm: Enable seccomp architecture tracking arm64: Enable seccomp architecture tracking selftests/seccomp: Compare bitmap vs filter overhead x86: Enable seccomp architecture tracking seccomp/cache: Add "emulator" to check if filter is constant allow seccomp/cache: Lookup syscall allowlist bitmap for fast path

Merge branch 'akpm' (patches from Andrew)

2020-12-16T07:26:37+00:00

Merge yet more updates from Andrew Morton: - lots of little subsystems - a few post-linux-next MM material. Most of the rest awaits more merging of other trees. Subsystems affected by this series: alpha, procfs, misc, core-kernel, bitmap, lib, lz4, checkpatch, nilfs, kdump, rapidio, gcov, bfs, relay, resource, ubsan, reboot, fault-injection, lzo, apparmor, and mm (swap, memory-hotplug, pagemap, cleanups, and gup). * emailed patches from Andrew Morton : (86 commits) mm: fix some spelling mistakes in comments mm: simplify follow_pte{,pmd} mm: unexport follow_pte_pmd apparmor: remove duplicate macro list_entry_is_head() lib/lzo/lzo1x_compress.c: make lzogeneric1x_1_compress() static fault-injection: handle EI_ETYPE_TRUE reboot: hide from sysfs not applicable settings reboot: allow to override reboot type if quirks are found reboot: remove cf9_safe from allowed types and rename cf9_force reboot: allow to specify reboot mode via sysfs reboot: refactor and comment the cpu selection code lib/ubsan.c: mark type_check_kinds with static keyword kcov: don't instrument with UBSAN ubsan: expand tests and reporting ubsan: remove UBSAN_MISC in favor of individual options ubsan: enable for all*config builds ubsan: disable UBSAN_TRAP for all*config ubsan: disable object-size sanitizer under GCC ubsan: move cc-option tests into Kconfig ubsan: remove redundant -Wno-maybe-uninitialized ...