Hi, On 10/17/23 at 05:26pm, Dan Carpenter wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > head: 213f891525c222e8ed145ce1ce7ae1f47921cb9c > commit: 4c91c07c93bbbdd7f2d9de2beb7ee5c2a48ad8e7 mm: vmalloc: convert vread() to vread_iter() > config: x86_64-allnoconfig (https://download.01.org/0day-ci/archive/20231017/202310171600.WCrsOwFj-lkp@xxxxxxxxx/config) > compiler: gcc-12 (Debian 12.2.0-14) 12.2.0 > reproduce: (https://download.01.org/0day-ci/archive/20231017/202310171600.WCrsOwFj-lkp@xxxxxxxxx/reproduce) > > If you fix the issue in a separate patch/commit (i.e. not just a new version of > the same patch/commit), kindly add following tags > | Reported-by: kernel test robot <lkp@xxxxxxxxx> > | Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > | Closes: https://lore.kernel.org/r/202310171600.WCrsOwFj-lkp@xxxxxxxxx/ > > smatch warnings: > mm/vmalloc.c:3689 vread_iter() error: we previously assumed 'vm' could be null (see line 3667) I see the code deficit, while the reproduce link seems to be unavilable. Could you double check the link and provide a good one so that I can verify the code fix? Thanks Baoquan > > vim +/vm +3689 mm/vmalloc.c > > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3619 long vread_iter(struct iov_iter *iter, const char *addr, size_t count) > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3620 { > e81ce85f960c2e Joonsoo Kim 2013-04-29 3621 struct vmap_area *va; > e81ce85f960c2e Joonsoo Kim 2013-04-29 3622 struct vm_struct *vm; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3623 char *vaddr; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3624 size_t n, size, flags, remains; > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3625 > 4aff1dc4fb3a5a Andrey Konovalov 2022-03-24 3626 addr = kasan_reset_tag(addr); > 4aff1dc4fb3a5a Andrey Konovalov 2022-03-24 3627 > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3628 /* Don't allow overflow */ > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3629 if ((unsigned long) addr + count < count) > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3630 count = -(unsigned long) addr; > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3631 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3632 remains = count; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3633 > e81ce85f960c2e Joonsoo Kim 2013-04-29 3634 spin_lock(&vmap_area_lock); > f181234a5a21fd Chen Wandun 2021-09-02 3635 va = find_vmap_area_exceed_addr((unsigned long)addr); > f608788cd2d6ca Serapheim Dimitropoulos 2021-04-29 3636 if (!va) > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3637 goto finished_zero; > f181234a5a21fd Chen Wandun 2021-09-02 3638 > f181234a5a21fd Chen Wandun 2021-09-02 3639 /* no intersects with alive vmap_area */ > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3640 if ((unsigned long)addr + remains <= va->va_start) > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3641 goto finished_zero; > f181234a5a21fd Chen Wandun 2021-09-02 3642 > f608788cd2d6ca Serapheim Dimitropoulos 2021-04-29 3643 list_for_each_entry_from(va, &vmap_area_list, list) { > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3644 size_t copied; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3645 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3646 if (remains == 0) > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3647 goto finished; > e81ce85f960c2e Joonsoo Kim 2013-04-29 3648 > 06c8994626d1b7 Baoquan He 2023-02-06 3649 vm = va->vm; > 06c8994626d1b7 Baoquan He 2023-02-06 3650 flags = va->flags & VMAP_FLAGS_MASK; > 06c8994626d1b7 Baoquan He 2023-02-06 3651 /* > 06c8994626d1b7 Baoquan He 2023-02-06 3652 * VMAP_BLOCK indicates a sub-type of vm_map_ram area, need > 06c8994626d1b7 Baoquan He 2023-02-06 3653 * be set together with VMAP_RAM. > 06c8994626d1b7 Baoquan He 2023-02-06 3654 */ > 06c8994626d1b7 Baoquan He 2023-02-06 3655 WARN_ON(flags == VMAP_BLOCK); > 06c8994626d1b7 Baoquan He 2023-02-06 3656 > 06c8994626d1b7 Baoquan He 2023-02-06 3657 if (!vm && !flags) > > NULL check > > e81ce85f960c2e Joonsoo Kim 2013-04-29 3658 continue; > e81ce85f960c2e Joonsoo Kim 2013-04-29 3659 > 30a7a9b17c4b03 Baoquan He 2023-02-06 3660 if (vm && (vm->flags & VM_UNINITIALIZED)) > 30a7a9b17c4b03 Baoquan He 2023-02-06 3661 continue; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3662 > 30a7a9b17c4b03 Baoquan He 2023-02-06 3663 /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */ > 30a7a9b17c4b03 Baoquan He 2023-02-06 3664 smp_rmb(); > 30a7a9b17c4b03 Baoquan He 2023-02-06 3665 > 06c8994626d1b7 Baoquan He 2023-02-06 3666 vaddr = (char *) va->va_start; > 06c8994626d1b7 Baoquan He 2023-02-06 @3667 size = vm ? get_vm_area_size(vm) : va_size(va); > 06c8994626d1b7 Baoquan He 2023-02-06 3668 > 06c8994626d1b7 Baoquan He 2023-02-06 3669 if (addr >= vaddr + size) > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3670 continue; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3671 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3672 if (addr < vaddr) { > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3673 size_t to_zero = min_t(size_t, vaddr - addr, remains); > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3674 size_t zeroed = zero_iter(iter, to_zero); > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3675 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3676 addr += zeroed; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3677 remains -= zeroed; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3678 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3679 if (remains == 0 || zeroed != to_zero) > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3680 goto finished; > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3681 } > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3682 > 06c8994626d1b7 Baoquan He 2023-02-06 3683 n = vaddr + size - addr; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3684 if (n > remains) > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3685 n = remains; > 06c8994626d1b7 Baoquan He 2023-02-06 3686 > 06c8994626d1b7 Baoquan He 2023-02-06 3687 if (flags & VMAP_RAM) > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3688 copied = vmap_ram_vread_iter(iter, addr, n, flags); > 06c8994626d1b7 Baoquan He 2023-02-06 @3689 else if (!(vm->flags & VM_IOREMAP)) > ^^^^^^^^^ > Unchecked dereference > > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3690 copied = aligned_vread_iter(iter, addr, n); > d0107eb07320b5 KAMEZAWA Hiroyuki 2009-09-21 3691 else /* IOREMAP area is treated as memory hole */ > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3692 copied = zero_iter(iter, n); > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3693 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3694 addr += copied; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3695 remains -= copied; > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3696 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3697 if (copied != n) > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3698 goto finished; > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3699 } > d0107eb07320b5 KAMEZAWA Hiroyuki 2009-09-21 3700 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3701 finished_zero: > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3702 spin_unlock(&vmap_area_lock); > d0107eb07320b5 KAMEZAWA Hiroyuki 2009-09-21 3703 /* zero-fill memory holes */ > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3704 return count - remains + zero_iter(iter, remains); > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3705 finished: > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3706 /* Nothing remains, or We couldn't copy/zero everything. */ > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3707 spin_unlock(&vmap_area_lock); > d0107eb07320b5 KAMEZAWA Hiroyuki 2009-09-21 3708 > 4c91c07c93bbbd Lorenzo Stoakes 2023-03-22 3709 return count - remains; > ^1da177e4c3f41 Linus Torvalds 2005-04-16 3710 } > > -- > 0-DAY CI Kernel Test Service > https://github.com/intel/lkp-tests/wiki >
