https://bugzilla.kernel.org/show_bug.cgi?id=216073 --- Comment #11 from willy@xxxxxxxxxxxxx --- On Sun, Jun 12, 2022 at 12:42:30PM +0800, Zorro Lang wrote: > Looks likt it's not a s390x specific bug, I just hit this issue once (not > 100% > reproducible) on aarch64 with linux v5.19.0-rc1+ [1]. So back to cc linux-mm > to get more review. > > [1] > [ 980.200947] usercopy: Kernel memory exposure attempt detected from vmalloc > 'no area' (offset 0, size 1)! if (is_vmalloc_addr(ptr)) { struct vm_struct *area = find_vm_area(ptr); if (!area) { usercopy_abort("vmalloc", "no area", to_user, 0, n); Oh. Looks like XFS uses vm_map_ram() and vm_map_ram() doesn't allocate a vm_struct. Ulad, how does this look to you? diff --git a/mm/usercopy.c b/mm/usercopy.c index baeacc735b83..6bc2a1407c59 100644 --- a/mm/usercopy.c +++ b/mm/usercopy.c @@ -173,7 +173,7 @@ static inline void check_heap_object(const void *ptr, unsigned long n, } if (is_vmalloc_addr(ptr)) { - struct vm_struct *area = find_vm_area(ptr); + struct vmap_area *area = find_vmap_area((unsigned long)ptr); unsigned long offset; if (!area) { @@ -181,8 +181,9 @@ static inline void check_heap_object(const void *ptr, unsigned long n, return; } - offset = ptr - area->addr; - if (offset + n > get_vm_area_size(area)) + /* XXX: We should also abort for free vmap_areas */ + offset = (unsigned long)ptr - area->va_start; + if (offset + n >= area->va_end) usercopy_abort("vmalloc", NULL, to_user, offset, n); return; } diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 07db42455dd4..effd1ff6a4b4 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1798,7 +1798,7 @@ static void free_unmap_vmap_area(struct vmap_area *va) free_vmap_area_noflush(va); } -static struct vmap_area *find_vmap_area(unsigned long addr) +struct vmap_area *find_vmap_area(unsigned long addr) { struct vmap_area *va; > [ 980.200968] ------------[ cut here ]------------ > [ 980.200969] kernel BUG at mm/usercopy.c:101! > [ 980.201081] Internal error: Oops - BUG: 0 [#1] SMP > [ 980.224192] Modules linked in: rfkill arm_spe_pmu mlx5_ib ast > drm_vram_helper drm_ttm_helper ttm ib_uverbs acpi_ipmi drm_kms_helper > ipmi_ssif fb_sys_fops syscopyarea sysfillrect ib_core sysimgblt arm_cmn > arm_dmc620_pmu arm_dsu_pmu cppc_cpufreq sunrpc vfat fat drm fuse xfs > libcrc32c mlx5_core crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce > sbsa_gwdt nvme igb mlxfw nvme_core tls i2c_algo_bit psample pci_hyperv_intf > i2c_designware_platform i2c_designware_core xgene_hwmon ipmi_devintf > ipmi_msghandler > [ 980.268449] CPU: 42 PID: 121940 Comm: rm Kdump: loaded Not tainted > 5.19.0-rc1+ #1 > [ 980.275921] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F16f > (SCP: 1.06.20210615) 07/01/2021 > [ 980.285214] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS > BTYPE=--) > [ 980.292165] pc : usercopy_abort+0x78/0x7c > [ 980.296167] lr : usercopy_abort+0x78/0x7c > [ 980.300166] sp : ffff80002b007730 > [ 980.303469] x29: ffff80002b007740 x28: ffff80002b007cc0 x27: > ffffdc5683ecc880 > [ 980.310595] x26: 1ffff00005600f9b x25: ffffdc5681c90000 x24: > ffff80002b007cdc > [ 980.317722] x23: ffff800041a0004a x22: 0000000000000001 x21: > 0000000000000001 > [ 980.324848] x20: 0000000000000000 x19: ffff800041a00049 x18: > 0000000000000000 > [ 980.331974] x17: 2720636f6c6c616d x16: 76206d6f72662064 x15: > 6574636574656420 > [ 980.339101] x14: 74706d6574746120 x13: 21293120657a6973 x12: > ffff6106cbc4c03f > [ 980.346227] x11: 1fffe106cbc4c03e x10: ffff6106cbc4c03e x9 : > ffffdc5681f36e30 > [ 980.353353] x8 : ffff08365e2601f7 x7 : 0000000000000001 x6 : > ffff6106cbc4c03e > [ 980.360480] x5 : ffff08365e2601f0 x4 : 1fffe10044b11801 x3 : > 0000000000000000 > [ 980.367606] x2 : 0000000000000000 x1 : ffff08022588c000 x0 : > 000000000000005c > [ 980.374733] Call trace: > [ 980.377167] usercopy_abort+0x78/0x7c > [ 980.380819] check_heap_object+0x3dc/0x3e0 > [ 980.384907] __check_object_size.part.0+0x6c/0x1f0 > [ 980.389688] __check_object_size+0x24/0x30 > [ 980.393774] filldir64+0x548/0x84c > [ 980.397165] xfs_dir2_block_getdents+0x404/0x960 [xfs] > [ 980.402437] xfs_readdir+0x3c4/0x4b0 [xfs] > [ 980.406652] xfs_file_readdir+0x6c/0xa0 [xfs] > [ 980.411127] iterate_dir+0x3a4/0x500 -- You may reply to this email to add a comment. You are receiving this mail because: You are watching someone on the CC list of the bug.
