Linux-stable-mirror

linux-stable-mirror@lists.linaro.org

266 participants
124087 discussions

FAILED: patch "[PATCH] RDMA/uverbs: Fix slab-out-of-bounds in" failed to apply to 4.14-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 4fae7f170416f970e5655f7e945ce69286b1c4ff Mon Sep 17 00:00:00 2001 From: Leon Romanovsky <leonro(a)mellanox.com> Date: Sun, 24 Jun 2018 11:23:53 +0300 Subject: [PATCH] RDMA/uverbs: Fix slab-out-of-bounds in ib_uverbs_ex_create_flow The check of cmd.flow_attr.size should check into account the size of the reserved field (2 bytes), otherwise user can provide a size which will cause a slab-out-of-bounds warning below. ================================================================== BUG: KASAN: slab-out-of-bounds in ib_uverbs_ex_create_flow+0x1740/0x1d00 Read of size 2 at addr ffff880068dff1a6 by task syz-executor775/269 CPU: 0 PID: 269 Comm: syz-executor775 Not tainted 4.18.0-rc1+ #245 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014 Call Trace: dump_stack+0xef/0x17e print_address_description+0x83/0x3b0 kasan_report+0x18d/0x4d0 ib_uverbs_ex_create_flow+0x1740/0x1d00 ib_uverbs_write+0x923/0x1010 __vfs_write+0x10d/0x720 vfs_write+0x1b0/0x550 ksys_write+0xc6/0x1a0 do_syscall_64+0xa7/0x590 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x433899 Code: fd ff 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 91 fd ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc2724db58 EFLAGS: 00000217 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000020006880 RCX: 0000000000433899 RDX: 00000000000000e0 RSI: 0000000020002480 RDI: 0000000000000003 RBP: 00000000006d7018 R08: 00000000004002f8 R09: 00000000004002f8 R10: 00000000004002f8 R11: 0000000000000217 R12: 0000000000000000 R13: 000000000040cd20 R14: 000000000040cdb0 R15: 0000000000000006 Allocated by task 269: kasan_kmalloc+0xa0/0xd0 __kmalloc+0x1a9/0x510 ib_uverbs_ex_create_flow+0x26c/0x1d00 ib_uverbs_write+0x923/0x1010 __vfs_write+0x10d/0x720 vfs_write+0x1b0/0x550 ksys_write+0xc6/0x1a0 do_syscall_64+0xa7/0x590 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 0: __kasan_slab_free+0x12e/0x180 kfree+0x159/0x630 detach_buf+0x559/0x7a0 virtqueue_get_buf_ctx+0x3cc/0xab0 virtblk_done+0x1eb/0x3d0 vring_interrupt+0x16d/0x2b0 __handle_irq_event_percpu+0x10a/0x980 handle_irq_event_percpu+0x77/0x190 handle_irq_event+0xc6/0x1a0 handle_edge_irq+0x211/0xd80 handle_irq+0x3d/0x60 do_IRQ+0x9b/0x220 The buggy address belongs to the object at ffff880068dff180 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 38 bytes inside of 64-byte region [ffff880068dff180, ffff880068dff1c0) The buggy address belongs to the page: page:ffffea0001a37fc0 count:1 mapcount:0 mapping:ffff88006c401780 index:0x0 flags: 0x4000000000000100(slab) raw: 4000000000000100 ffffea0001a31100 0000001100000011 ffff88006c401780 raw: 0000000000000000 00000000802a002a 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff880068dff080: fb fb fb fb fc fc fc fc fb fb fb fb fb fb fb fb ffff880068dff100: fc fc fc fc fb fb fb fb fb fb fb fb fc fc fc fc >ffff880068dff180: 00 00 00 00 07 fc fc fc fc fc fc fc fb fb fb fb ^ ffff880068dff200: fb fb fb fb fc fc fc fc 00 00 00 00 00 00 fc fc ffff880068dff280: fc fc fc fc 00 00 00 00 00 00 00 00 fc fc fc fc ================================================================== Cc: <stable(a)vger.kernel.org> # 3.12 Fixes: f88482743872 ("IB/core: clarify overflow/underflow checks on ib_create/destroy_flow") Cc: syzkaller <syzkaller(a)googlegroups.com> Reported-by: Noa Osherovich <noaos(a)mellanox.com> Signed-off-by: Leon Romanovsky <leonro(a)mellanox.com> Signed-off-by: Jason Gunthorpe <jgg(a)mellanox.com> diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index 89c4ce2da78b..87ffeebc0b28 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -3488,8 +3488,8 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file, struct ib_flow_attr *flow_attr; struct ib_qp *qp; struct ib_uflow_resources *uflow_res; + struct ib_uverbs_flow_spec_hdr *kern_spec; int err = 0; - void *kern_spec; void *ib_spec; int i; @@ -3538,8 +3538,8 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file, if (!kern_flow_attr) return -ENOMEM; - memcpy(kern_flow_attr, &cmd.flow_attr, sizeof(*kern_flow_attr)); - err = ib_copy_from_udata(kern_flow_attr + 1, ucore, + *kern_flow_attr = cmd.flow_attr; + err = ib_copy_from_udata(&kern_flow_attr->flow_specs, ucore, cmd.flow_attr.size); if (err) goto err_free_attr; @@ -3583,21 +3583,22 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file, flow_attr->flags = kern_flow_attr->flags; flow_attr->size = sizeof(*flow_attr); - kern_spec = kern_flow_attr + 1; + kern_spec = kern_flow_attr->flow_specs; ib_spec = flow_attr + 1; for (i = 0; i < flow_attr->num_of_specs && - cmd.flow_attr.size > offsetof(struct ib_uverbs_flow_spec, reserved) && - cmd.flow_attr.size >= - ((struct ib_uverbs_flow_spec *)kern_spec)->size; i++) { - err = kern_spec_to_ib_spec(file->ucontext, kern_spec, ib_spec, - uflow_res); + cmd.flow_attr.size > sizeof(*kern_spec) && + cmd.flow_attr.size >= kern_spec->size; + i++) { + err = kern_spec_to_ib_spec( + file->ucontext, (struct ib_uverbs_flow_spec *)kern_spec, + ib_spec, uflow_res); if (err) goto err_free; flow_attr->size += ((union ib_flow_spec *) ib_spec)->size; - cmd.flow_attr.size -= ((struct ib_uverbs_flow_spec *)kern_spec)->size; - kern_spec += ((struct ib_uverbs_flow_spec *) kern_spec)->size; + cmd.flow_attr.size -= kern_spec->size; + kern_spec = ((void *)kern_spec) + kern_spec->size; ib_spec += ((union ib_flow_spec *) ib_spec)->size; } if (cmd.flow_attr.size || (i != flow_attr->num_of_specs)) {

7 years, 5 months

FAILED: patch "[PATCH] RDMA/uverbs: Fix slab-out-of-bounds in" failed to apply to 4.17-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.17-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 4fae7f170416f970e5655f7e945ce69286b1c4ff Mon Sep 17 00:00:00 2001 From: Leon Romanovsky <leonro(a)mellanox.com> Date: Sun, 24 Jun 2018 11:23:53 +0300 Subject: [PATCH] RDMA/uverbs: Fix slab-out-of-bounds in ib_uverbs_ex_create_flow The check of cmd.flow_attr.size should check into account the size of the reserved field (2 bytes), otherwise user can provide a size which will cause a slab-out-of-bounds warning below. ================================================================== BUG: KASAN: slab-out-of-bounds in ib_uverbs_ex_create_flow+0x1740/0x1d00 Read of size 2 at addr ffff880068dff1a6 by task syz-executor775/269 CPU: 0 PID: 269 Comm: syz-executor775 Not tainted 4.18.0-rc1+ #245 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014 Call Trace: dump_stack+0xef/0x17e print_address_description+0x83/0x3b0 kasan_report+0x18d/0x4d0 ib_uverbs_ex_create_flow+0x1740/0x1d00 ib_uverbs_write+0x923/0x1010 __vfs_write+0x10d/0x720 vfs_write+0x1b0/0x550 ksys_write+0xc6/0x1a0 do_syscall_64+0xa7/0x590 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x433899 Code: fd ff 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 91 fd ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc2724db58 EFLAGS: 00000217 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000020006880 RCX: 0000000000433899 RDX: 00000000000000e0 RSI: 0000000020002480 RDI: 0000000000000003 RBP: 00000000006d7018 R08: 00000000004002f8 R09: 00000000004002f8 R10: 00000000004002f8 R11: 0000000000000217 R12: 0000000000000000 R13: 000000000040cd20 R14: 000000000040cdb0 R15: 0000000000000006 Allocated by task 269: kasan_kmalloc+0xa0/0xd0 __kmalloc+0x1a9/0x510 ib_uverbs_ex_create_flow+0x26c/0x1d00 ib_uverbs_write+0x923/0x1010 __vfs_write+0x10d/0x720 vfs_write+0x1b0/0x550 ksys_write+0xc6/0x1a0 do_syscall_64+0xa7/0x590 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 0: __kasan_slab_free+0x12e/0x180 kfree+0x159/0x630 detach_buf+0x559/0x7a0 virtqueue_get_buf_ctx+0x3cc/0xab0 virtblk_done+0x1eb/0x3d0 vring_interrupt+0x16d/0x2b0 __handle_irq_event_percpu+0x10a/0x980 handle_irq_event_percpu+0x77/0x190 handle_irq_event+0xc6/0x1a0 handle_edge_irq+0x211/0xd80 handle_irq+0x3d/0x60 do_IRQ+0x9b/0x220 The buggy address belongs to the object at ffff880068dff180 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 38 bytes inside of 64-byte region [ffff880068dff180, ffff880068dff1c0) The buggy address belongs to the page: page:ffffea0001a37fc0 count:1 mapcount:0 mapping:ffff88006c401780 index:0x0 flags: 0x4000000000000100(slab) raw: 4000000000000100 ffffea0001a31100 0000001100000011 ffff88006c401780 raw: 0000000000000000 00000000802a002a 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff880068dff080: fb fb fb fb fc fc fc fc fb fb fb fb fb fb fb fb ffff880068dff100: fc fc fc fc fb fb fb fb fb fb fb fb fc fc fc fc >ffff880068dff180: 00 00 00 00 07 fc fc fc fc fc fc fc fb fb fb fb ^ ffff880068dff200: fb fb fb fb fc fc fc fc 00 00 00 00 00 00 fc fc ffff880068dff280: fc fc fc fc 00 00 00 00 00 00 00 00 fc fc fc fc ================================================================== Cc: <stable(a)vger.kernel.org> # 3.12 Fixes: f88482743872 ("IB/core: clarify overflow/underflow checks on ib_create/destroy_flow") Cc: syzkaller <syzkaller(a)googlegroups.com> Reported-by: Noa Osherovich <noaos(a)mellanox.com> Signed-off-by: Leon Romanovsky <leonro(a)mellanox.com> Signed-off-by: Jason Gunthorpe <jgg(a)mellanox.com> diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index 89c4ce2da78b..87ffeebc0b28 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -3488,8 +3488,8 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file, struct ib_flow_attr *flow_attr; struct ib_qp *qp; struct ib_uflow_resources *uflow_res; + struct ib_uverbs_flow_spec_hdr *kern_spec; int err = 0; - void *kern_spec; void *ib_spec; int i; @@ -3538,8 +3538,8 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file, if (!kern_flow_attr) return -ENOMEM; - memcpy(kern_flow_attr, &cmd.flow_attr, sizeof(*kern_flow_attr)); - err = ib_copy_from_udata(kern_flow_attr + 1, ucore, + *kern_flow_attr = cmd.flow_attr; + err = ib_copy_from_udata(&kern_flow_attr->flow_specs, ucore, cmd.flow_attr.size); if (err) goto err_free_attr; @@ -3583,21 +3583,22 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file, flow_attr->flags = kern_flow_attr->flags; flow_attr->size = sizeof(*flow_attr); - kern_spec = kern_flow_attr + 1; + kern_spec = kern_flow_attr->flow_specs; ib_spec = flow_attr + 1; for (i = 0; i < flow_attr->num_of_specs && - cmd.flow_attr.size > offsetof(struct ib_uverbs_flow_spec, reserved) && - cmd.flow_attr.size >= - ((struct ib_uverbs_flow_spec *)kern_spec)->size; i++) { - err = kern_spec_to_ib_spec(file->ucontext, kern_spec, ib_spec, - uflow_res); + cmd.flow_attr.size > sizeof(*kern_spec) && + cmd.flow_attr.size >= kern_spec->size; + i++) { + err = kern_spec_to_ib_spec( + file->ucontext, (struct ib_uverbs_flow_spec *)kern_spec, + ib_spec, uflow_res); if (err) goto err_free; flow_attr->size += ((union ib_flow_spec *) ib_spec)->size; - cmd.flow_attr.size -= ((struct ib_uverbs_flow_spec *)kern_spec)->size; - kern_spec += ((struct ib_uverbs_flow_spec *) kern_spec)->size; + cmd.flow_attr.size -= kern_spec->size; + kern_spec = ((void *)kern_spec) + kern_spec->size; ib_spec += ((union ib_flow_spec *) ib_spec)->size; } if (cmd.flow_attr.size || (i != flow_attr->num_of_specs)) {

7 years, 5 months

Fix "x86/e820: put !E820_TYPE_RAM regions into memblock.reserved"

by Linus Torvalds

Just a note that I just pushed out commit e181ae0c5db9 ("mm: zero unavailable pages before memmap init") that fixes the nasty VM crash issue I had, and that apparently the Fedora people have also seen in the wild in 4.17.4. The commit that triggered this didn't make it in until 4.18-rc3, but it has apparently already been back-ported to stable, so now the fix needs to be back-ported too. Linus

7 years, 5 months

[PATCH] random: mix rdrand with entropy sent in from userspace

by Theodore Ts'o

Fedora has integrated the jitter entropy daemon to work around slow boot problems, especially on VM's that don't support virtio-rng: https://bugzilla.redhat.com/show_bug.cgi?id=1572944 It's understandable why they did this, but the Jitter entropy daemon works fundamentally on the principle: "the CPU microarchitecture is **so** complicated and we can't figure it out, so it *must* be random". Yes, it uses statistical tests to "prove" it is secure, but AES_ENCRYPT(NSA_KEY, COUNTER++) will also pass statistical tests with flying colors. So if RDRAND is available, mix it into entropy submitted from userspace. It can't hurt, and if you believe the NSA has backdoored RDRAND, then they probably have enough details about the Intel microarchitecture that they can reverse engineer how the Jitter entropy daemon affects the microarchitecture, and attack its output stream. And if RDRAND is in fact an honest DRNG, it will immeasurably improve on what the Jitter entropy daemon might produce. This also provides some protection against someone who is able to read or set the entropy seed file. Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Cc: stable(a)vger.kernel.org --- drivers/char/random.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 0706646b018d..283fe390e878 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1896,14 +1896,22 @@ static int write_pool(struct entropy_store *r, const char __user *buffer, size_t count) { size_t bytes; - __u32 buf[16]; + __u32 t, buf[16]; const char __user *p = buffer; while (count > 0) { + int b, i = 0; + bytes = min(count, sizeof(buf)); if (copy_from_user(&buf, p, bytes)) return -EFAULT; + for (b = bytes ; b > 0 ; b -= sizeof(__u32), i++) { + if (arch_get_random_int(&t)) + continue; + buf[i] ^= t; + } + count -= bytes; p += bytes; -- 2.18.0.rc0

7 years, 5 months

[PATCH 1/4] mtd: rawnand: add missing error handling in subop helpers

by Miquel Raynal

A report from Colin Ian King pointed a CoverityScan issue where error values on these helpers where not checked in the drivers. These helpers could error out only in case of a software bug in driver code, not because of a runtime/hardware error but in any cases it is safer to handle these errors properly. Before fixing the drivers, let's add some consistency and fix these helpers error handling. Fixes: 8878b126df76 ("mtd: nand: add ->exec_op() implementation") Cc: stable(a)vger.kernel.org Signed-off-by: Miquel Raynal <miquel.raynal(a)bootlin.com> --- drivers/mtd/nand/raw/nand_base.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index 10c4f9919850..51f68203aa63 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -2720,6 +2720,8 @@ int nand_subop_get_num_addr_cyc(const struct nand_subop *subop, return -EINVAL; start_off = nand_subop_get_addr_start_off(subop, instr_idx); + if (start_off < 0) + return start_off; if (instr_idx == subop->ninstrs - 1 && subop->last_instr_end_off) @@ -2774,6 +2776,8 @@ int nand_subop_get_data_len(const struct nand_subop *subop, return -EINVAL; start_off = nand_subop_get_data_start_off(subop, instr_idx); + if (start_off < 0) + return start_off; if (instr_idx == subop->ninstrs - 1 && subop->last_instr_end_off) -- 2.14.1

7 years, 5 months

[PATCH 4.4.y 101/101] x86/bugs: Rename SSBD_NO to SSB_NO

by Srivatsa S. Bhat

From: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com> commit 240da953fcc6a9008c92fae5b1f727ee5ed167ab upstream The "336996 Speculative Execution Side Channel Mitigations" from May defines this as SSB_NO, hence lets sync-up. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa(a)csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley(a)gmail.com> Reviewed-by: Alexey Makhalov <amakhalov(a)vmware.com> Reviewed-by: Bo Gan <ganb(a)vmware.com> --- arch/x86/include/asm/msr-index.h | 2 +- arch/x86/kernel/cpu/common.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 22f2dd5..caa0019 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -58,7 +58,7 @@ #define MSR_IA32_ARCH_CAPABILITIES 0x0000010a #define ARCH_CAP_RDCL_NO (1 << 0) /* Not susceptible to Meltdown */ #define ARCH_CAP_IBRS_ALL (1 << 1) /* Enhanced IBRS support */ -#define ARCH_CAP_SSBD_NO (1 << 4) /* +#define ARCH_CAP_SSB_NO (1 << 4) /* * Not susceptible to Speculative Store Bypass * attack, so no Speculative Store Bypass * control required. diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 1097723..9ad38ad 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -881,7 +881,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c) rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap); if (!x86_match_cpu(cpu_no_spec_store_bypass) && - !(ia32_cap & ARCH_CAP_SSBD_NO)) + !(ia32_cap & ARCH_CAP_SSB_NO)) setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS); if (x86_match_cpu(cpu_no_speculation))

7 years, 5 months

[PATCH 4.4.y 100/101] x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFG

by Srivatsa S. Bhat

From: Thomas Gleixner <tglx(a)linutronix.de> commit 47c61b3955cf712cadfc25635bf9bc174af030ea upstream Add the necessary logic for supporting the emulated VIRT_SPEC_CTRL MSR to x86_virt_spec_ctrl(). If either X86_FEATURE_LS_CFG_SSBD or X86_FEATURE_VIRT_SPEC_CTRL is set then use the new guest_virt_spec_ctrl argument to check whether the state must be modified on the host. The update reuses speculative_store_bypass_update() so the ZEN-specific sibling coordination can be reused. Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa(a)csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley(a)gmail.com> Reviewed-by: Alexey Makhalov <amakhalov(a)vmware.com> Reviewed-by: Bo Gan <ganb(a)vmware.com> --- arch/x86/include/asm/spec-ctrl.h | 6 ++++++ arch/x86/kernel/cpu/bugs.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+) diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h index 763d497..ae7c2c5 100644 --- a/arch/x86/include/asm/spec-ctrl.h +++ b/arch/x86/include/asm/spec-ctrl.h @@ -53,6 +53,12 @@ static inline u64 ssbd_tif_to_spec_ctrl(u64 tifn) return (tifn & _TIF_SSBD) >> (TIF_SSBD - SPEC_CTRL_SSBD_SHIFT); } +static inline unsigned long ssbd_spec_ctrl_to_tif(u64 spec_ctrl) +{ + BUILD_BUG_ON(TIF_SSBD < SPEC_CTRL_SSBD_SHIFT); + return (spec_ctrl & SPEC_CTRL_SSBD) << (TIF_SSBD - SPEC_CTRL_SSBD_SHIFT); +} + static inline u64 ssbd_tif_to_amd_ls_cfg(u64 tifn) { return (tifn & _TIF_SSBD) ? x86_amd_ls_cfg_ssbd_mask : 0ULL; diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index af11a02..12a8867 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -160,6 +160,36 @@ x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest) wrmsrl(MSR_IA32_SPEC_CTRL, msrval); } } + + /* + * If SSBD is not handled in MSR_SPEC_CTRL on AMD, update + * MSR_AMD64_L2_CFG or MSR_VIRT_SPEC_CTRL if supported. + */ + if (!static_cpu_has(X86_FEATURE_LS_CFG_SSBD) && + !static_cpu_has(X86_FEATURE_VIRT_SSBD)) + return; + + /* + * If the host has SSBD mitigation enabled, force it in the host's + * virtual MSR value. If its not permanently enabled, evaluate + * current's TIF_SSBD thread flag. + */ + if (static_cpu_has(X86_FEATURE_SPEC_STORE_BYPASS_DISABLE)) + hostval = SPEC_CTRL_SSBD; + else + hostval = ssbd_tif_to_spec_ctrl(ti->flags); + + /* Sanitize the guest value */ + guestval = guest_virt_spec_ctrl & SPEC_CTRL_SSBD; + + if (hostval != guestval) { + unsigned long tif; + + tif = setguest ? ssbd_spec_ctrl_to_tif(guestval) : + ssbd_spec_ctrl_to_tif(hostval); + + speculative_store_bypass_update(tif); + } } EXPORT_SYMBOL_GPL(x86_virt_spec_ctrl);

7 years, 5 months

[PATCH 4.4.y 099/101] x86/bugs: Rework spec_ctrl base and mask logic

by Srivatsa S. Bhat

From: Thomas Gleixner <tglx(a)linutronix.de> commit be6fcb5478e95bb1c91f489121238deb3abca46a upstream x86_spec_ctrL_mask is intended to mask out bits from a MSR_SPEC_CTRL value which are not to be modified. However the implementation is not really used and the bitmask was inverted to make a check easier, which was removed in "x86/bugs: Remove x86_spec_ctrl_set()" Aside of that it is missing the STIBP bit if it is supported by the platform, so if the mask would be used in x86_virt_spec_ctrl() then it would prevent a guest from setting STIBP. Add the STIBP bit if supported and use the mask in x86_virt_spec_ctrl() to sanitize the value which is supplied by the guest. Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Reviewed-by: Borislav Petkov <bp(a)suse.de> Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa(a)csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley(a)gmail.com> Reviewed-by: Alexey Makhalov <amakhalov(a)vmware.com> Reviewed-by: Bo Gan <ganb(a)vmware.com> --- arch/x86/kernel/cpu/bugs.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 05eed68..af11a02 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -41,7 +41,7 @@ EXPORT_SYMBOL_GPL(x86_spec_ctrl_base); * The vendor and possibly platform specific bits which can be modified in * x86_spec_ctrl_base. */ -static u64 x86_spec_ctrl_mask = ~SPEC_CTRL_IBRS; +static u64 x86_spec_ctrl_mask = SPEC_CTRL_IBRS; /* * AMD specific MSR info for Speculative Store Bypass control. @@ -67,6 +67,10 @@ void __init check_bugs(void) if (boot_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) rdmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base); + /* Allow STIBP in MSR_SPEC_CTRL if supported */ + if (boot_cpu_has(X86_FEATURE_STIBP)) + x86_spec_ctrl_mask |= SPEC_CTRL_STIBP; + /* Select the proper spectre mitigation before patching alternatives */ spectre_v2_select_mitigation(); @@ -134,18 +138,26 @@ static enum spectre_v2_mitigation spectre_v2_enabled = SPECTRE_V2_NONE; void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest) { + u64 msrval, guestval, hostval = x86_spec_ctrl_base; struct thread_info *ti = current_thread_info(); - u64 msr, host = x86_spec_ctrl_base; /* Is MSR_SPEC_CTRL implemented ? */ if (static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) { + /* + * Restrict guest_spec_ctrl to supported values. Clear the + * modifiable bits in the host base value and or the + * modifiable bits from the guest value. + */ + guestval = hostval & ~x86_spec_ctrl_mask; + guestval |= guest_spec_ctrl & x86_spec_ctrl_mask; + /* SSBD controlled in MSR_SPEC_CTRL */ if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD)) - host |= ssbd_tif_to_spec_ctrl(ti->flags); + hostval |= ssbd_tif_to_spec_ctrl(ti->flags); - if (host != guest_spec_ctrl) { - msr = setguest ? guest_spec_ctrl : host; - wrmsrl(MSR_IA32_SPEC_CTRL, msr); + if (hostval != guestval) { + msrval = setguest ? guestval : hostval; + wrmsrl(MSR_IA32_SPEC_CTRL, msrval); } } } @@ -491,7 +503,7 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void) switch (boot_cpu_data.x86_vendor) { case X86_VENDOR_INTEL: x86_spec_ctrl_base |= SPEC_CTRL_SSBD; - x86_spec_ctrl_mask &= ~SPEC_CTRL_SSBD; + x86_spec_ctrl_mask |= SPEC_CTRL_SSBD; wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base); break; case X86_VENDOR_AMD:

7 years, 5 months

[PATCH 4.4.y 098/101] x86/bugs: Remove x86_spec_ctrl_set()

by Srivatsa S. Bhat

From: Thomas Gleixner <tglx(a)linutronix.de> commit 4b59bdb569453a60b752b274ca61f009e37f4dae upstream x86_spec_ctrl_set() is only used in bugs.c and the extra mask checks there provide no real value as both call sites can just write x86_spec_ctrl_base to MSR_SPEC_CTRL. x86_spec_ctrl_base is valid and does not need any extra masking or checking. Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Reviewed-by: Borislav Petkov <bp(a)suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com> Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa(a)csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley(a)gmail.com> Reviewed-by: Alexey Makhalov <amakhalov(a)vmware.com> Reviewed-by: Bo Gan <ganb(a)vmware.com> --- arch/x86/include/asm/nospec-branch.h | 2 -- arch/x86/kernel/cpu/bugs.c | 13 ++----------- 2 files changed, 2 insertions(+), 13 deletions(-) diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index 2757c79..b4c74c2 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -172,8 +172,6 @@ enum spectre_v2_mitigation { SPECTRE_V2_IBRS, }; -extern void x86_spec_ctrl_set(u64); - /* The Speculative Store Bypass disable variants */ enum ssb_mitigation { SPEC_STORE_BYPASS_NONE, diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 5391df5..05eed68 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -131,15 +131,6 @@ static const char *spectre_v2_strings[] = { static enum spectre_v2_mitigation spectre_v2_enabled = SPECTRE_V2_NONE; -void x86_spec_ctrl_set(u64 val) -{ - if (val & x86_spec_ctrl_mask) - WARN_ONCE(1, "SPEC_CTRL MSR value 0x%16llx is unknown.\n", val); - else - wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base | val); -} -EXPORT_SYMBOL_GPL(x86_spec_ctrl_set); - void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest) { @@ -501,7 +492,7 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void) case X86_VENDOR_INTEL: x86_spec_ctrl_base |= SPEC_CTRL_SSBD; x86_spec_ctrl_mask &= ~SPEC_CTRL_SSBD; - x86_spec_ctrl_set(SPEC_CTRL_SSBD); + wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base); break; case X86_VENDOR_AMD: x86_amd_ssb_disable(); @@ -613,7 +604,7 @@ int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which) void x86_spec_ctrl_setup_ap(void) { if (boot_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) - x86_spec_ctrl_set(x86_spec_ctrl_base & ~x86_spec_ctrl_mask); + wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base); if (ssb_mode == SPEC_STORE_BYPASS_DISABLE) x86_amd_ssb_disable();

7 years, 5 months

[PATCH 4.4.y 097/101] x86/bugs: Expose x86_spec_ctrl_base directly

by Srivatsa S. Bhat

From: Thomas Gleixner <tglx(a)linutronix.de> commit fa8ac4988249c38476f6ad678a4848a736373403 upstream x86_spec_ctrl_base is the system wide default value for the SPEC_CTRL MSR. x86_spec_ctrl_get_default() returns x86_spec_ctrl_base and was intended to prevent modification to that variable. Though the variable is read only after init and globaly visible already. Remove the function and export the variable instead. Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Reviewed-by: Borislav Petkov <bp(a)suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com> Signed-off-by: David Woodhouse <dwmw(a)amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa(a)csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley(a)gmail.com> Reviewed-by: Alexey Makhalov <amakhalov(a)vmware.com> Reviewed-by: Bo Gan <ganb(a)vmware.com> --- arch/x86/include/asm/nospec-branch.h | 16 +++++----------- arch/x86/include/asm/spec-ctrl.h | 3 --- arch/x86/kernel/cpu/bugs.c | 11 +---------- 3 files changed, 6 insertions(+), 24 deletions(-) diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index 640c11b..2757c79 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -172,16 +172,7 @@ enum spectre_v2_mitigation { SPECTRE_V2_IBRS, }; -/* - * The Intel specification for the SPEC_CTRL MSR requires that we - * preserve any already set reserved bits at boot time (e.g. for - * future additions that this kernel is not currently aware of). - * We then set any additional mitigation bits that we want - * ourselves and always use this as the base for SPEC_CTRL. - * We also use this when handling guest entry/exit as below. - */ extern void x86_spec_ctrl_set(u64); -extern u64 x86_spec_ctrl_get_default(void); /* The Speculative Store Bypass disable variants */ enum ssb_mitigation { @@ -232,6 +223,9 @@ static inline void indirect_branch_prediction_barrier(void) alternative_msr_write(MSR_IA32_PRED_CMD, val, X86_FEATURE_USE_IBPB); } +/* The Intel SPEC CTRL MSR base value cache */ +extern u64 x86_spec_ctrl_base; + /* * With retpoline, we must use IBRS to restrict branch prediction * before calling into firmware. @@ -240,7 +234,7 @@ static inline void indirect_branch_prediction_barrier(void) */ #define firmware_restrict_branch_speculation_start() \ do { \ - u64 val = x86_spec_ctrl_get_default() | SPEC_CTRL_IBRS; \ + u64 val = x86_spec_ctrl_base | SPEC_CTRL_IBRS; \ \ preempt_disable(); \ alternative_msr_write(MSR_IA32_SPEC_CTRL, val, \ @@ -249,7 +243,7 @@ do { \ #define firmware_restrict_branch_speculation_end() \ do { \ - u64 val = x86_spec_ctrl_get_default(); \ + u64 val = x86_spec_ctrl_base; \ \ alternative_msr_write(MSR_IA32_SPEC_CTRL, val, \ X86_FEATURE_USE_IBRS_FW); \ diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h index 9cecbe5..763d497 100644 --- a/arch/x86/include/asm/spec-ctrl.h +++ b/arch/x86/include/asm/spec-ctrl.h @@ -47,9 +47,6 @@ void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl) extern u64 x86_amd_ls_cfg_base; extern u64 x86_amd_ls_cfg_ssbd_mask; -/* The Intel SPEC CTRL MSR base value cache */ -extern u64 x86_spec_ctrl_base; - static inline u64 ssbd_tif_to_spec_ctrl(u64 tifn) { BUILD_BUG_ON(TIF_SSBD < SPEC_CTRL_SSBD_SHIFT); diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 208d44c..5391df5 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -35,6 +35,7 @@ static void __init ssb_select_mitigation(void); * writes to SPEC_CTRL contain whatever reserved bits have been set. */ u64 x86_spec_ctrl_base; +EXPORT_SYMBOL_GPL(x86_spec_ctrl_base); /* * The vendor and possibly platform specific bits which can be modified in @@ -139,16 +140,6 @@ void x86_spec_ctrl_set(u64 val) } EXPORT_SYMBOL_GPL(x86_spec_ctrl_set); -u64 x86_spec_ctrl_get_default(void) -{ - u64 msrval = x86_spec_ctrl_base; - - if (static_cpu_has(X86_FEATURE_SPEC_CTRL)) - msrval |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags); - return msrval; -} -EXPORT_SYMBOL_GPL(x86_spec_ctrl_get_default); - void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest) {

7 years, 5 months

Jump to page:

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror