summaryrefslogtreecommitdiffstats
path: root/arch/x86
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/Kconfig8
-rw-r--r--arch/x86/boot/compressed/head_64.S5
-rw-r--r--arch/x86/crypto/nh-avx2-x86_64.S1
-rw-r--r--arch/x86/crypto/sha256-avx2-asm.S1
-rw-r--r--arch/x86/crypto/sha512-avx2-asm.S1
-rw-r--r--arch/x86/entry/vsyscall/vsyscall_64.c28
-rw-r--r--arch/x86/include/asm/cmpxchg_64.h2
-rw-r--r--arch/x86/include/asm/pgtable_types.h2
-rw-r--r--arch/x86/include/asm/processor.h1
-rw-r--r--arch/x86/include/asm/sparsemem.h2
-rw-r--r--arch/x86/kernel/cpu/microcode/amd.c2
-rw-r--r--arch/x86/kernel/tsc_sync.c6
-rw-r--r--arch/x86/lib/x86-opcode-map.txt10
-rw-r--r--arch/x86/mm/fault.c33
-rw-r--r--arch/x86/mm/numa.c4
-rw-r--r--arch/x86/mm/pat/set_memory.c68
-rw-r--r--arch/x86/net/bpf_jit_comp.c57
-rw-r--r--arch/x86/purgatory/Makefile3
-rw-r--r--arch/x86/tools/relocs.c9
19 files changed, 120 insertions, 123 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 6f49999a6b..bfccf12138 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2474,9 +2474,13 @@ menuconfig CPU_MITIGATIONS
help
Say Y here to enable options which enable mitigations for hardware
vulnerabilities (usually related to speculative execution).
+ Mitigations can be disabled or restricted to SMT systems at runtime
+ via the "mitigations" kernel parameter.
- If you say N, all mitigations will be disabled. You really
- should know what you are doing to say so.
+ If you say N, all mitigations will be disabled. This CANNOT be
+ overridden at runtime.
+
+ Say 'Y', unless you really know what you are doing.
if CPU_MITIGATIONS
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index bf4a10a579..1dcb794c54 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -398,6 +398,11 @@ SYM_CODE_START(startup_64)
call sev_enable
#endif
+ /* Preserve only the CR4 bits that must be preserved, and clear the rest */
+ movq %cr4, %rax
+ andl $(X86_CR4_PAE | X86_CR4_MCE | X86_CR4_LA57), %eax
+ movq %rax, %cr4
+
/*
* configure_5level_paging() updates the number of paging levels using
* a trampoline in 32-bit addressable memory if the current number does
diff --git a/arch/x86/crypto/nh-avx2-x86_64.S b/arch/x86/crypto/nh-avx2-x86_64.S
index ef73a3ab87..791386d9a8 100644
--- a/arch/x86/crypto/nh-avx2-x86_64.S
+++ b/arch/x86/crypto/nh-avx2-x86_64.S
@@ -154,5 +154,6 @@ SYM_TYPED_FUNC_START(nh_avx2)
vpaddq T1, T0, T0
vpaddq T4, T0, T0
vmovdqu T0, (HASH)
+ vzeroupper
RET
SYM_FUNC_END(nh_avx2)
diff --git a/arch/x86/crypto/sha256-avx2-asm.S b/arch/x86/crypto/sha256-avx2-asm.S
index 9918212faf..0ffb072be9 100644
--- a/arch/x86/crypto/sha256-avx2-asm.S
+++ b/arch/x86/crypto/sha256-avx2-asm.S
@@ -716,6 +716,7 @@ SYM_TYPED_FUNC_START(sha256_transform_rorx)
popq %r13
popq %r12
popq %rbx
+ vzeroupper
RET
SYM_FUNC_END(sha256_transform_rorx)
diff --git a/arch/x86/crypto/sha512-avx2-asm.S b/arch/x86/crypto/sha512-avx2-asm.S
index f08496cd68..24973f42c4 100644
--- a/arch/x86/crypto/sha512-avx2-asm.S
+++ b/arch/x86/crypto/sha512-avx2-asm.S
@@ -680,6 +680,7 @@ SYM_TYPED_FUNC_START(sha512_transform_rorx)
pop %r12
pop %rbx
+ vzeroupper
RET
SYM_FUNC_END(sha512_transform_rorx)
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c
index e0ca8120ae..1245000a87 100644
--- a/arch/x86/entry/vsyscall/vsyscall_64.c
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -98,11 +98,6 @@ static int addr_to_vsyscall_nr(unsigned long addr)
static bool write_ok_or_segv(unsigned long ptr, size_t size)
{
- /*
- * XXX: if access_ok, get_user, and put_user handled
- * sig_on_uaccess_err, this could go away.
- */
-
if (!access_ok((void __user *)ptr, size)) {
struct thread_struct *thread = &current->thread;
@@ -120,10 +115,8 @@ static bool write_ok_or_segv(unsigned long ptr, size_t size)
bool emulate_vsyscall(unsigned long error_code,
struct pt_regs *regs, unsigned long address)
{
- struct task_struct *tsk;
unsigned long caller;
int vsyscall_nr, syscall_nr, tmp;
- int prev_sig_on_uaccess_err;
long ret;
unsigned long orig_dx;
@@ -172,8 +165,6 @@ bool emulate_vsyscall(unsigned long error_code,
goto sigsegv;
}
- tsk = current;
-
/*
* Check for access_ok violations and find the syscall nr.
*
@@ -234,12 +225,8 @@ bool emulate_vsyscall(unsigned long error_code,
goto do_ret; /* skip requested */
/*
- * With a real vsyscall, page faults cause SIGSEGV. We want to
- * preserve that behavior to make writing exploits harder.
+ * With a real vsyscall, page faults cause SIGSEGV.
*/
- prev_sig_on_uaccess_err = current->thread.sig_on_uaccess_err;
- current->thread.sig_on_uaccess_err = 1;
-
ret = -EFAULT;
switch (vsyscall_nr) {
case 0:
@@ -262,23 +249,12 @@ bool emulate_vsyscall(unsigned long error_code,
break;
}
- current->thread.sig_on_uaccess_err = prev_sig_on_uaccess_err;
-
check_fault:
if (ret == -EFAULT) {
/* Bad news -- userspace fed a bad pointer to a vsyscall. */
warn_bad_vsyscall(KERN_INFO, regs,
"vsyscall fault (exploit attempt?)");
-
- /*
- * If we failed to generate a signal for any reason,
- * generate one here. (This should be impossible.)
- */
- if (WARN_ON_ONCE(!sigismember(&tsk->pending.signal, SIGBUS) &&
- !sigismember(&tsk->pending.signal, SIGSEGV)))
- goto sigsegv;
-
- return true; /* Don't emulate the ret. */
+ goto sigsegv;
}
regs->ax = ret;
diff --git a/arch/x86/include/asm/cmpxchg_64.h b/arch/x86/include/asm/cmpxchg_64.h
index 44b08b53ab..c1d6cd58f8 100644
--- a/arch/x86/include/asm/cmpxchg_64.h
+++ b/arch/x86/include/asm/cmpxchg_64.h
@@ -62,7 +62,7 @@ static __always_inline u128 arch_cmpxchg128_local(volatile u128 *ptr, u128 old,
asm volatile(_lock "cmpxchg16b %[ptr]" \
CC_SET(e) \
: CC_OUT(e) (ret), \
- [ptr] "+m" (*ptr), \
+ [ptr] "+m" (*(_ptr)), \
"+a" (o.low), "+d" (o.high) \
: "b" (n.low), "c" (n.high) \
: "memory"); \
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 9abb8cc4cd..b786449626 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -567,6 +567,8 @@ static inline void update_page_count(int level, unsigned long pages) { }
extern pte_t *lookup_address(unsigned long address, unsigned int *level);
extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
unsigned int *level);
+pte_t *lookup_address_in_pgd_attr(pgd_t *pgd, unsigned long address,
+ unsigned int *level, bool *nx, bool *rw);
extern pmd_t *lookup_pmd_address(unsigned long address);
extern phys_addr_t slow_virt_to_phys(void *__address);
extern int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn,
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 26620d7642..5636ad6973 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -479,7 +479,6 @@ struct thread_struct {
unsigned long iopl_emul;
unsigned int iopl_warn:1;
- unsigned int sig_on_uaccess_err:1;
/*
* Protection Keys Register for Userspace. Loaded immediately on
diff --git a/arch/x86/include/asm/sparsemem.h b/arch/x86/include/asm/sparsemem.h
index 1be13b2dfe..64df897c0e 100644
--- a/arch/x86/include/asm/sparsemem.h
+++ b/arch/x86/include/asm/sparsemem.h
@@ -37,8 +37,6 @@ extern int phys_to_target_node(phys_addr_t start);
#define phys_to_target_node phys_to_target_node
extern int memory_add_physaddr_to_nid(u64 start);
#define memory_add_physaddr_to_nid memory_add_physaddr_to_nid
-extern int numa_fill_memblks(u64 start, u64 end);
-#define numa_fill_memblks numa_fill_memblks
#endif
#endif /* __ASSEMBLY__ */
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 13b45b9c80..620f0af713 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -465,7 +465,7 @@ static bool early_apply_microcode(u32 cpuid_1_eax, u32 old_rev, void *ucode, siz
return !__apply_microcode_amd(mc);
}
-static bool get_builtin_microcode(struct cpio_data *cp, unsigned int family)
+static bool get_builtin_microcode(struct cpio_data *cp, u8 family)
{
char fw_name[36] = "amd-ucode/microcode_amd.bin";
struct firmware fw;
diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c
index 1123ef3ccf..4334033658 100644
--- a/arch/x86/kernel/tsc_sync.c
+++ b/arch/x86/kernel/tsc_sync.c
@@ -193,11 +193,9 @@ bool tsc_store_and_check_tsc_adjust(bool bootcpu)
cur->warned = false;
/*
- * If a non-zero TSC value for socket 0 may be valid then the default
- * adjusted value cannot assumed to be zero either.
+ * The default adjust value cannot be assumed to be zero on any socket.
*/
- if (tsc_async_resets)
- cur->adjusted = bootval;
+ cur->adjusted = bootval;
/*
* Check whether this CPU is the first in a package to come up. In
diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt
index 5168ee0360..d1ccd06c53 100644
--- a/arch/x86/lib/x86-opcode-map.txt
+++ b/arch/x86/lib/x86-opcode-map.txt
@@ -148,7 +148,7 @@ AVXcode:
65: SEG=GS (Prefix)
66: Operand-Size (Prefix)
67: Address-Size (Prefix)
-68: PUSH Iz (d64)
+68: PUSH Iz
69: IMUL Gv,Ev,Iz
6a: PUSH Ib (d64)
6b: IMUL Gv,Ev,Ib
@@ -698,10 +698,10 @@ AVXcode: 2
4d: vrcp14ss/d Vsd,Hpd,Wsd (66),(ev)
4e: vrsqrt14ps/d Vpd,Wpd (66),(ev)
4f: vrsqrt14ss/d Vsd,Hsd,Wsd (66),(ev)
-50: vpdpbusd Vx,Hx,Wx (66),(ev)
-51: vpdpbusds Vx,Hx,Wx (66),(ev)
-52: vdpbf16ps Vx,Hx,Wx (F3),(ev) | vpdpwssd Vx,Hx,Wx (66),(ev) | vp4dpwssd Vdqq,Hdqq,Wdq (F2),(ev)
-53: vpdpwssds Vx,Hx,Wx (66),(ev) | vp4dpwssds Vdqq,Hdqq,Wdq (F2),(ev)
+50: vpdpbusd Vx,Hx,Wx (66)
+51: vpdpbusds Vx,Hx,Wx (66)
+52: vdpbf16ps Vx,Hx,Wx (F3),(ev) | vpdpwssd Vx,Hx,Wx (66) | vp4dpwssd Vdqq,Hdqq,Wdq (F2),(ev)
+53: vpdpwssds Vx,Hx,Wx (66) | vp4dpwssds Vdqq,Hdqq,Wdq (F2),(ev)
54: vpopcntb/w Vx,Wx (66),(ev)
55: vpopcntd/q Vx,Wx (66),(ev)
58: vpbroadcastd Vx,Wx (66),(v)
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index b01df023de..e604d2d6cc 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -717,39 +717,8 @@ kernelmode_fixup_or_oops(struct pt_regs *regs, unsigned long error_code,
WARN_ON_ONCE(user_mode(regs));
/* Are we prepared to handle this kernel fault? */
- if (fixup_exception(regs, X86_TRAP_PF, error_code, address)) {
- /*
- * Any interrupt that takes a fault gets the fixup. This makes
- * the below recursive fault logic only apply to a faults from
- * task context.
- */
- if (in_interrupt())
- return;
-
- /*
- * Per the above we're !in_interrupt(), aka. task context.
- *
- * In this case we need to make sure we're not recursively
- * faulting through the emulate_vsyscall() logic.
- */
- if (current->thread.sig_on_uaccess_err && signal) {
- sanitize_error_code(address, &error_code);
-
- set_signal_archinfo(address, error_code);
-
- if (si_code == SEGV_PKUERR) {
- force_sig_pkuerr((void __user *)address, pkey);
- } else {
- /* XXX: hwpoison faults will set the wrong code. */
- force_sig_fault(signal, si_code, (void __user *)address);
- }
- }
-
- /*
- * Barring that, we can do the fixup and be happy.
- */
+ if (fixup_exception(regs, X86_TRAP_PF, error_code, address))
return;
- }
/*
* AMD erratum #91 manifests as a spurious page fault on a PREFETCH
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index 65e9a6e391..ce84ba86e6 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -929,6 +929,8 @@ int memory_add_physaddr_to_nid(u64 start)
}
EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
+#endif
+
static int __init cmp_memblk(const void *a, const void *b)
{
const struct numa_memblk *ma = *(const struct numa_memblk **)a;
@@ -1001,5 +1003,3 @@ int __init numa_fill_memblks(u64 start, u64 end)
}
return 0;
}
-
-#endif
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 135bb594df..b4073fb452 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -619,7 +619,8 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long start,
* Validate strict W^X semantics.
*/
static inline pgprot_t verify_rwx(pgprot_t old, pgprot_t new, unsigned long start,
- unsigned long pfn, unsigned long npg)
+ unsigned long pfn, unsigned long npg,
+ bool nx, bool rw)
{
unsigned long end;
@@ -641,6 +642,10 @@ static inline pgprot_t verify_rwx(pgprot_t old, pgprot_t new, unsigned long star
if ((pgprot_val(new) & (_PAGE_RW | _PAGE_NX)) != _PAGE_RW)
return new;
+ /* Non-leaf translation entries can disable writing or execution. */
+ if (!rw || nx)
+ return new;
+
end = start + npg * PAGE_SIZE - 1;
WARN_ONCE(1, "CPA detected W^X violation: %016llx -> %016llx range: 0x%016lx - 0x%016lx PFN %lx\n",
(unsigned long long)pgprot_val(old),
@@ -657,20 +662,26 @@ static inline pgprot_t verify_rwx(pgprot_t old, pgprot_t new, unsigned long star
/*
* Lookup the page table entry for a virtual address in a specific pgd.
- * Return a pointer to the entry and the level of the mapping.
+ * Return a pointer to the entry, the level of the mapping, and the effective
+ * NX and RW bits of all page table levels.
*/
-pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
- unsigned int *level)
+pte_t *lookup_address_in_pgd_attr(pgd_t *pgd, unsigned long address,
+ unsigned int *level, bool *nx, bool *rw)
{
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
*level = PG_LEVEL_NONE;
+ *nx = false;
+ *rw = true;
if (pgd_none(*pgd))
return NULL;
+ *nx |= pgd_flags(*pgd) & _PAGE_NX;
+ *rw &= pgd_flags(*pgd) & _PAGE_RW;
+
p4d = p4d_offset(pgd, address);
if (p4d_none(*p4d))
return NULL;
@@ -679,6 +690,9 @@ pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
if (p4d_large(*p4d) || !p4d_present(*p4d))
return (pte_t *)p4d;
+ *nx |= p4d_flags(*p4d) & _PAGE_NX;
+ *rw &= p4d_flags(*p4d) & _PAGE_RW;
+
pud = pud_offset(p4d, address);
if (pud_none(*pud))
return NULL;
@@ -687,6 +701,9 @@ pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
if (pud_leaf(*pud) || !pud_present(*pud))
return (pte_t *)pud;
+ *nx |= pud_flags(*pud) & _PAGE_NX;
+ *rw &= pud_flags(*pud) & _PAGE_RW;
+
pmd = pmd_offset(pud, address);
if (pmd_none(*pmd))
return NULL;
@@ -695,12 +712,27 @@ pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
if (pmd_large(*pmd) || !pmd_present(*pmd))
return (pte_t *)pmd;
+ *nx |= pmd_flags(*pmd) & _PAGE_NX;
+ *rw &= pmd_flags(*pmd) & _PAGE_RW;
+
*level = PG_LEVEL_4K;
return pte_offset_kernel(pmd, address);
}
/*
+ * Lookup the page table entry for a virtual address in a specific pgd.
+ * Return a pointer to the entry and the level of the mapping.
+ */
+pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
+ unsigned int *level)
+{
+ bool nx, rw;
+
+ return lookup_address_in_pgd_attr(pgd, address, level, &nx, &rw);
+}
+
+/*
* Lookup the page table entry for a virtual address. Return a pointer
* to the entry and the level of the mapping.
*
@@ -715,13 +747,16 @@ pte_t *lookup_address(unsigned long address, unsigned int *level)
EXPORT_SYMBOL_GPL(lookup_address);
static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
- unsigned int *level)
+ unsigned int *level, bool *nx, bool *rw)
{
- if (cpa->pgd)
- return lookup_address_in_pgd(cpa->pgd + pgd_index(address),
- address, level);
+ pgd_t *pgd;
+
+ if (!cpa->pgd)
+ pgd = pgd_offset_k(address);
+ else
+ pgd = cpa->pgd + pgd_index(address);
- return lookup_address(address, level);
+ return lookup_address_in_pgd_attr(pgd, address, level, nx, rw);
}
/*
@@ -849,12 +884,13 @@ static int __should_split_large_page(pte_t *kpte, unsigned long address,
pgprot_t old_prot, new_prot, req_prot, chk_prot;
pte_t new_pte, *tmp;
enum pg_level level;
+ bool nx, rw;
/*
* Check for races, another CPU might have split this page
* up already:
*/
- tmp = _lookup_address_cpa(cpa, address, &level);
+ tmp = _lookup_address_cpa(cpa, address, &level, &nx, &rw);
if (tmp != kpte)
return 1;
@@ -965,7 +1001,8 @@ static int __should_split_large_page(pte_t *kpte, unsigned long address,
new_prot = static_protections(req_prot, lpaddr, old_pfn, numpages,
psize, CPA_DETECT);
- new_prot = verify_rwx(old_prot, new_prot, lpaddr, old_pfn, numpages);
+ new_prot = verify_rwx(old_prot, new_prot, lpaddr, old_pfn, numpages,
+ nx, rw);
/*
* If there is a conflict, split the large page.
@@ -1046,6 +1083,7 @@ __split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
pte_t *pbase = (pte_t *)page_address(base);
unsigned int i, level;
pgprot_t ref_prot;
+ bool nx, rw;
pte_t *tmp;
spin_lock(&pgd_lock);
@@ -1053,7 +1091,7 @@ __split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
* Check for races, another CPU might have split this page
* up for us already:
*/
- tmp = _lookup_address_cpa(cpa, address, &level);
+ tmp = _lookup_address_cpa(cpa, address, &level, &nx, &rw);
if (tmp != kpte) {
spin_unlock(&pgd_lock);
return 1;
@@ -1594,10 +1632,11 @@ static int __change_page_attr(struct cpa_data *cpa, int primary)
int do_split, err;
unsigned int level;
pte_t *kpte, old_pte;
+ bool nx, rw;
address = __cpa_addr(cpa, cpa->curpage);
repeat:
- kpte = _lookup_address_cpa(cpa, address, &level);
+ kpte = _lookup_address_cpa(cpa, address, &level, &nx, &rw);
if (!kpte)
return __cpa_process_fault(cpa, address, primary);
@@ -1619,7 +1658,8 @@ repeat:
new_prot = static_protections(new_prot, address, pfn, 1, 0,
CPA_PROTECT);
- new_prot = verify_rwx(old_prot, new_prot, address, pfn, 1);
+ new_prot = verify_rwx(old_prot, new_prot, address, pfn, 1,
+ nx, rw);
new_prot = pgprot_clear_protnone_bits(new_prot);
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index df484885cc..f415c2cf53 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1585,36 +1585,41 @@ st: if (is_imm8(insn->off))
if (BPF_MODE(insn->code) == BPF_PROBE_MEM ||
BPF_MODE(insn->code) == BPF_PROBE_MEMSX) {
/* Conservatively check that src_reg + insn->off is a kernel address:
- * src_reg + insn->off >= TASK_SIZE_MAX + PAGE_SIZE
- * src_reg is used as scratch for src_reg += insn->off and restored
- * after emit_ldx if necessary
+ * src_reg + insn->off > TASK_SIZE_MAX + PAGE_SIZE
+ * and
+ * src_reg + insn->off < VSYSCALL_ADDR
*/
- u64 limit = TASK_SIZE_MAX + PAGE_SIZE;
+ u64 limit = TASK_SIZE_MAX + PAGE_SIZE - VSYSCALL_ADDR;
u8 *end_of_jmp;
- /* At end of these emitted checks, insn->off will have been added
- * to src_reg, so no need to do relative load with insn->off offset
- */
- insn_off = 0;
+ /* movabsq r10, VSYSCALL_ADDR */
+ emit_mov_imm64(&prog, BPF_REG_AX, (long)VSYSCALL_ADDR >> 32,
+ (u32)(long)VSYSCALL_ADDR);
- /* movabsq r11, limit */
- EMIT2(add_1mod(0x48, AUX_REG), add_1reg(0xB8, AUX_REG));
- EMIT((u32)limit, 4);
- EMIT(limit >> 32, 4);
+ /* mov src_reg, r11 */
+ EMIT_mov(AUX_REG, src_reg);
if (insn->off) {
- /* add src_reg, insn->off */
- maybe_emit_1mod(&prog, src_reg, true);
- EMIT2_off32(0x81, add_1reg(0xC0, src_reg), insn->off);
+ /* add r11, insn->off */
+ maybe_emit_1mod(&prog, AUX_REG, true);
+ EMIT2_off32(0x81, add_1reg(0xC0, AUX_REG), insn->off);
}
- /* cmp src_reg, r11 */
- maybe_emit_mod(&prog, src_reg, AUX_REG, true);
- EMIT2(0x39, add_2reg(0xC0, src_reg, AUX_REG));
+ /* sub r11, r10 */
+ maybe_emit_mod(&prog, AUX_REG, BPF_REG_AX, true);
+ EMIT2(0x29, add_2reg(0xC0, AUX_REG, BPF_REG_AX));
+
+ /* movabsq r10, limit */
+ emit_mov_imm64(&prog, BPF_REG_AX, (long)limit >> 32,
+ (u32)(long)limit);
+
+ /* cmp r10, r11 */
+ maybe_emit_mod(&prog, AUX_REG, BPF_REG_AX, true);
+ EMIT2(0x39, add_2reg(0xC0, AUX_REG, BPF_REG_AX));
- /* if unsigned '>=', goto load */
- EMIT2(X86_JAE, 0);
+ /* if unsigned '>', goto load */
+ EMIT2(X86_JA, 0);
end_of_jmp = prog;
/* xor dst_reg, dst_reg */
@@ -1640,18 +1645,6 @@ st: if (is_imm8(insn->off))
/* populate jmp_offset for JMP above */
start_of_ldx[-1] = prog - start_of_ldx;
- if (insn->off && src_reg != dst_reg) {
- /* sub src_reg, insn->off
- * Restore src_reg after "add src_reg, insn->off" in prev
- * if statement. But if src_reg == dst_reg, emit_ldx
- * above already clobbered src_reg, so no need to restore.
- * If add src_reg, insn->off was unnecessary, no need to
- * restore either.
- */
- maybe_emit_1mod(&prog, src_reg, true);
- EMIT2_off32(0x81, add_1reg(0xE8, src_reg), insn->off);
- }
-
if (!bpf_prog->aux->extable)
break;
diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
index 08aa0f25f1..8d1c82795e 100644
--- a/arch/x86/purgatory/Makefile
+++ b/arch/x86/purgatory/Makefile
@@ -42,7 +42,8 @@ KCOV_INSTRUMENT := n
# make up the standalone purgatory.ro
PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel
-PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss -g0
+PURGATORY_CFLAGS := -mcmodel=small -ffreestanding -fno-zero-initialized-in-bss -g0
+PURGATORY_CFLAGS += -fpic -fvisibility=hidden
PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING
PURGATORY_CFLAGS += -fno-stack-protector
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index b029fb81eb..e7a44a7f61 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -746,6 +746,15 @@ static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel,
if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
continue;
}
+
+ /*
+ * Do not perform relocations in .notes sections; any
+ * values there are meant for pre-boot consumption (e.g.
+ * startup_xen).
+ */
+ if (sec_applies->shdr.sh_type == SHT_NOTE)
+ continue;
+
sh_symtab = sec_symtab->symtab;
sym_strtab = sec_symtab->link->strtab;
for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 18:09:53 +0000