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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/x86/kernel/signal_64.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'arch/x86/kernel/signal_64.c')
-rw-r--r--arch/x86/kernel/signal_64.c510
1 files changed, 510 insertions, 0 deletions
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
new file mode 100644
index 000000000..13a1e6083
--- /dev/null
+++ b/arch/x86/kernel/signal_64.c
@@ -0,0 +1,510 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/unistd.h>
+#include <linux/uaccess.h>
+#include <linux/syscalls.h>
+
+#include <asm/ucontext.h>
+#include <asm/fpu/signal.h>
+#include <asm/sighandling.h>
+
+#include <asm/syscall.h>
+#include <asm/sigframe.h>
+#include <asm/signal.h>
+
+/*
+ * If regs->ss will cause an IRET fault, change it. Otherwise leave it
+ * alone. Using this generally makes no sense unless
+ * user_64bit_mode(regs) would return true.
+ */
+static void force_valid_ss(struct pt_regs *regs)
+{
+ u32 ar;
+ asm volatile ("lar %[old_ss], %[ar]\n\t"
+ "jz 1f\n\t" /* If invalid: */
+ "xorl %[ar], %[ar]\n\t" /* set ar = 0 */
+ "1:"
+ : [ar] "=r" (ar)
+ : [old_ss] "rm" ((u16)regs->ss));
+
+ /*
+ * For a valid 64-bit user context, we need DPL 3, type
+ * read-write data or read-write exp-down data, and S and P
+ * set. We can't use VERW because VERW doesn't check the
+ * P bit.
+ */
+ ar &= AR_DPL_MASK | AR_S | AR_P | AR_TYPE_MASK;
+ if (ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA) &&
+ ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA_EXPDOWN))
+ regs->ss = __USER_DS;
+}
+
+static bool restore_sigcontext(struct pt_regs *regs,
+ struct sigcontext __user *usc,
+ unsigned long uc_flags)
+{
+ struct sigcontext sc;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ if (copy_from_user(&sc, usc, offsetof(struct sigcontext, reserved1)))
+ return false;
+
+ regs->bx = sc.bx;
+ regs->cx = sc.cx;
+ regs->dx = sc.dx;
+ regs->si = sc.si;
+ regs->di = sc.di;
+ regs->bp = sc.bp;
+ regs->ax = sc.ax;
+ regs->sp = sc.sp;
+ regs->ip = sc.ip;
+ regs->r8 = sc.r8;
+ regs->r9 = sc.r9;
+ regs->r10 = sc.r10;
+ regs->r11 = sc.r11;
+ regs->r12 = sc.r12;
+ regs->r13 = sc.r13;
+ regs->r14 = sc.r14;
+ regs->r15 = sc.r15;
+
+ /* Get CS/SS and force CPL3 */
+ regs->cs = sc.cs | 0x03;
+ regs->ss = sc.ss | 0x03;
+
+ regs->flags = (regs->flags & ~FIX_EFLAGS) | (sc.flags & FIX_EFLAGS);
+ /* disable syscall checks */
+ regs->orig_ax = -1;
+
+ /*
+ * Fix up SS if needed for the benefit of old DOSEMU and
+ * CRIU.
+ */
+ if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && user_64bit_mode(regs)))
+ force_valid_ss(regs);
+
+ return fpu__restore_sig((void __user *)sc.fpstate, 0);
+}
+
+static __always_inline int
+__unsafe_setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
+ struct pt_regs *regs, unsigned long mask)
+{
+ unsafe_put_user(regs->di, &sc->di, Efault);
+ unsafe_put_user(regs->si, &sc->si, Efault);
+ unsafe_put_user(regs->bp, &sc->bp, Efault);
+ unsafe_put_user(regs->sp, &sc->sp, Efault);
+ unsafe_put_user(regs->bx, &sc->bx, Efault);
+ unsafe_put_user(regs->dx, &sc->dx, Efault);
+ unsafe_put_user(regs->cx, &sc->cx, Efault);
+ unsafe_put_user(regs->ax, &sc->ax, Efault);
+ unsafe_put_user(regs->r8, &sc->r8, Efault);
+ unsafe_put_user(regs->r9, &sc->r9, Efault);
+ unsafe_put_user(regs->r10, &sc->r10, Efault);
+ unsafe_put_user(regs->r11, &sc->r11, Efault);
+ unsafe_put_user(regs->r12, &sc->r12, Efault);
+ unsafe_put_user(regs->r13, &sc->r13, Efault);
+ unsafe_put_user(regs->r14, &sc->r14, Efault);
+ unsafe_put_user(regs->r15, &sc->r15, Efault);
+
+ unsafe_put_user(current->thread.trap_nr, &sc->trapno, Efault);
+ unsafe_put_user(current->thread.error_code, &sc->err, Efault);
+ unsafe_put_user(regs->ip, &sc->ip, Efault);
+ unsafe_put_user(regs->flags, &sc->flags, Efault);
+ unsafe_put_user(regs->cs, &sc->cs, Efault);
+ unsafe_put_user(0, &sc->gs, Efault);
+ unsafe_put_user(0, &sc->fs, Efault);
+ unsafe_put_user(regs->ss, &sc->ss, Efault);
+
+ unsafe_put_user(fpstate, (unsigned long __user *)&sc->fpstate, Efault);
+
+ /* non-iBCS2 extensions.. */
+ unsafe_put_user(mask, &sc->oldmask, Efault);
+ unsafe_put_user(current->thread.cr2, &sc->cr2, Efault);
+ return 0;
+Efault:
+ return -EFAULT;
+}
+
+#define unsafe_put_sigcontext(sc, fp, regs, set, label) \
+do { \
+ if (__unsafe_setup_sigcontext(sc, fp, regs, set->sig[0])) \
+ goto label; \
+} while(0);
+
+#define unsafe_put_sigmask(set, frame, label) \
+ unsafe_put_user(*(__u64 *)(set), \
+ (__u64 __user *)&(frame)->uc.uc_sigmask, \
+ label)
+
+static unsigned long frame_uc_flags(struct pt_regs *regs)
+{
+ unsigned long flags;
+
+ if (boot_cpu_has(X86_FEATURE_XSAVE))
+ flags = UC_FP_XSTATE | UC_SIGCONTEXT_SS;
+ else
+ flags = UC_SIGCONTEXT_SS;
+
+ if (likely(user_64bit_mode(regs)))
+ flags |= UC_STRICT_RESTORE_SS;
+
+ return flags;
+}
+
+int x64_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
+{
+ sigset_t *set = sigmask_to_save();
+ struct rt_sigframe __user *frame;
+ void __user *fp = NULL;
+ unsigned long uc_flags;
+
+ /* x86-64 should always use SA_RESTORER. */
+ if (!(ksig->ka.sa.sa_flags & SA_RESTORER))
+ return -EFAULT;
+
+ frame = get_sigframe(ksig, regs, sizeof(struct rt_sigframe), &fp);
+ uc_flags = frame_uc_flags(regs);
+
+ if (!user_access_begin(frame, sizeof(*frame)))
+ return -EFAULT;
+
+ /* Create the ucontext. */
+ unsafe_put_user(uc_flags, &frame->uc.uc_flags, Efault);
+ unsafe_put_user(0, &frame->uc.uc_link, Efault);
+ unsafe_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ unsafe_put_user(ksig->ka.sa.sa_restorer, &frame->pretcode, Efault);
+ unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault);
+ unsafe_put_sigmask(set, frame, Efault);
+ user_access_end();
+
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
+ if (copy_siginfo_to_user(&frame->info, &ksig->info))
+ return -EFAULT;
+ }
+
+ /* Set up registers for signal handler */
+ regs->di = ksig->sig;
+ /* In case the signal handler was declared without prototypes */
+ regs->ax = 0;
+
+ /* This also works for non SA_SIGINFO handlers because they expect the
+ next argument after the signal number on the stack. */
+ regs->si = (unsigned long)&frame->info;
+ regs->dx = (unsigned long)&frame->uc;
+ regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
+
+ regs->sp = (unsigned long)frame;
+
+ /*
+ * Set up the CS and SS registers to run signal handlers in
+ * 64-bit mode, even if the handler happens to be interrupting
+ * 32-bit or 16-bit code.
+ *
+ * SS is subtle. In 64-bit mode, we don't need any particular
+ * SS descriptor, but we do need SS to be valid. It's possible
+ * that the old SS is entirely bogus -- this can happen if the
+ * signal we're trying to deliver is #GP or #SS caused by a bad
+ * SS value. We also have a compatibility issue here: DOSEMU
+ * relies on the contents of the SS register indicating the
+ * SS value at the time of the signal, even though that code in
+ * DOSEMU predates sigreturn's ability to restore SS. (DOSEMU
+ * avoids relying on sigreturn to restore SS; instead it uses
+ * a trampoline.) So we do our best: if the old SS was valid,
+ * we keep it. Otherwise we replace it.
+ */
+ regs->cs = __USER_CS;
+
+ if (unlikely(regs->ss != __USER_DS))
+ force_valid_ss(regs);
+
+ return 0;
+
+Efault:
+ user_access_end();
+ return -EFAULT;
+}
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+SYSCALL_DEFINE0(rt_sigreturn)
+{
+ struct pt_regs *regs = current_pt_regs();
+ struct rt_sigframe __user *frame;
+ sigset_t set;
+ unsigned long uc_flags;
+
+ frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
+ if (!access_ok(frame, sizeof(*frame)))
+ goto badframe;
+ if (__get_user(*(__u64 *)&set, (__u64 __user *)&frame->uc.uc_sigmask))
+ goto badframe;
+ if (__get_user(uc_flags, &frame->uc.uc_flags))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags))
+ goto badframe;
+
+ if (restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return regs->ax;
+
+badframe:
+ signal_fault(regs, frame, "rt_sigreturn");
+ return 0;
+}
+
+#ifdef CONFIG_X86_X32_ABI
+static int x32_copy_siginfo_to_user(struct compat_siginfo __user *to,
+ const struct kernel_siginfo *from)
+{
+ struct compat_siginfo new;
+
+ copy_siginfo_to_external32(&new, from);
+ if (from->si_signo == SIGCHLD) {
+ new._sifields._sigchld_x32._utime = from->si_utime;
+ new._sifields._sigchld_x32._stime = from->si_stime;
+ }
+ if (copy_to_user(to, &new, sizeof(struct compat_siginfo)))
+ return -EFAULT;
+ return 0;
+}
+
+int copy_siginfo_to_user32(struct compat_siginfo __user *to,
+ const struct kernel_siginfo *from)
+{
+ if (in_x32_syscall())
+ return x32_copy_siginfo_to_user(to, from);
+ return __copy_siginfo_to_user32(to, from);
+}
+
+int x32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
+{
+ compat_sigset_t *set = (compat_sigset_t *) sigmask_to_save();
+ struct rt_sigframe_x32 __user *frame;
+ unsigned long uc_flags;
+ void __user *restorer;
+ void __user *fp = NULL;
+
+ if (!(ksig->ka.sa.sa_flags & SA_RESTORER))
+ return -EFAULT;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame), &fp);
+
+ uc_flags = frame_uc_flags(regs);
+
+ if (!user_access_begin(frame, sizeof(*frame)))
+ return -EFAULT;
+
+ /* Create the ucontext. */
+ unsafe_put_user(uc_flags, &frame->uc.uc_flags, Efault);
+ unsafe_put_user(0, &frame->uc.uc_link, Efault);
+ unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
+ unsafe_put_user(0, &frame->uc.uc__pad0, Efault);
+ restorer = ksig->ka.sa.sa_restorer;
+ unsafe_put_user(restorer, (unsigned long __user *)&frame->pretcode, Efault);
+ unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault);
+ unsafe_put_sigmask(set, frame, Efault);
+ user_access_end();
+
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
+ if (x32_copy_siginfo_to_user(&frame->info, &ksig->info))
+ return -EFAULT;
+ }
+
+ /* Set up registers for signal handler */
+ regs->sp = (unsigned long) frame;
+ regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
+
+ /* We use the x32 calling convention here... */
+ regs->di = ksig->sig;
+ regs->si = (unsigned long) &frame->info;
+ regs->dx = (unsigned long) &frame->uc;
+
+ loadsegment(ds, __USER_DS);
+ loadsegment(es, __USER_DS);
+
+ regs->cs = __USER_CS;
+ regs->ss = __USER_DS;
+
+ return 0;
+
+Efault:
+ user_access_end();
+ return -EFAULT;
+}
+
+COMPAT_SYSCALL_DEFINE0(x32_rt_sigreturn)
+{
+ struct pt_regs *regs = current_pt_regs();
+ struct rt_sigframe_x32 __user *frame;
+ sigset_t set;
+ unsigned long uc_flags;
+
+ frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8);
+
+ if (!access_ok(frame, sizeof(*frame)))
+ goto badframe;
+ if (__get_user(set.sig[0], (__u64 __user *)&frame->uc.uc_sigmask))
+ goto badframe;
+ if (__get_user(uc_flags, &frame->uc.uc_flags))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags))
+ goto badframe;
+
+ if (compat_restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return regs->ax;
+
+badframe:
+ signal_fault(regs, frame, "x32 rt_sigreturn");
+ return 0;
+}
+#endif /* CONFIG_X86_X32_ABI */
+
+#ifdef CONFIG_COMPAT
+void sigaction_compat_abi(struct k_sigaction *act, struct k_sigaction *oact)
+{
+ if (!act)
+ return;
+
+ if (in_ia32_syscall())
+ act->sa.sa_flags |= SA_IA32_ABI;
+ if (in_x32_syscall())
+ act->sa.sa_flags |= SA_X32_ABI;
+}
+#endif /* CONFIG_COMPAT */
+
+/*
+* If adding a new si_code, there is probably new data in
+* the siginfo. Make sure folks bumping the si_code
+* limits also have to look at this code. Make sure any
+* new fields are handled in copy_siginfo_to_user32()!
+*/
+static_assert(NSIGILL == 11);
+static_assert(NSIGFPE == 15);
+static_assert(NSIGSEGV == 9);
+static_assert(NSIGBUS == 5);
+static_assert(NSIGTRAP == 6);
+static_assert(NSIGCHLD == 6);
+static_assert(NSIGSYS == 2);
+
+/* This is part of the ABI and can never change in size: */
+static_assert(sizeof(siginfo_t) == 128);
+
+/* This is a part of the ABI and can never change in alignment */
+static_assert(__alignof__(siginfo_t) == 8);
+
+/*
+* The offsets of all the (unioned) si_fields are fixed
+* in the ABI, of course. Make sure none of them ever
+* move and are always at the beginning:
+*/
+static_assert(offsetof(siginfo_t, si_signo) == 0);
+static_assert(offsetof(siginfo_t, si_errno) == 4);
+static_assert(offsetof(siginfo_t, si_code) == 8);
+
+/*
+* Ensure that the size of each si_field never changes.
+* If it does, it is a sign that the
+* copy_siginfo_to_user32() code below needs to updated
+* along with the size in the CHECK_SI_SIZE().
+*
+* We repeat this check for both the generic and compat
+* siginfos.
+*
+* Note: it is OK for these to grow as long as the whole
+* structure stays within the padding size (checked
+* above).
+*/
+
+#define CHECK_SI_OFFSET(name) \
+ static_assert(offsetof(siginfo_t, _sifields) == \
+ offsetof(siginfo_t, _sifields.name))
+#define CHECK_SI_SIZE(name, size) \
+ static_assert(sizeof_field(siginfo_t, _sifields.name) == size)
+
+CHECK_SI_OFFSET(_kill);
+CHECK_SI_SIZE (_kill, 2*sizeof(int));
+static_assert(offsetof(siginfo_t, si_pid) == 0x10);
+static_assert(offsetof(siginfo_t, si_uid) == 0x14);
+
+CHECK_SI_OFFSET(_timer);
+CHECK_SI_SIZE (_timer, 6*sizeof(int));
+static_assert(offsetof(siginfo_t, si_tid) == 0x10);
+static_assert(offsetof(siginfo_t, si_overrun) == 0x14);
+static_assert(offsetof(siginfo_t, si_value) == 0x18);
+
+CHECK_SI_OFFSET(_rt);
+CHECK_SI_SIZE (_rt, 4*sizeof(int));
+static_assert(offsetof(siginfo_t, si_pid) == 0x10);
+static_assert(offsetof(siginfo_t, si_uid) == 0x14);
+static_assert(offsetof(siginfo_t, si_value) == 0x18);
+
+CHECK_SI_OFFSET(_sigchld);
+CHECK_SI_SIZE (_sigchld, 8*sizeof(int));
+static_assert(offsetof(siginfo_t, si_pid) == 0x10);
+static_assert(offsetof(siginfo_t, si_uid) == 0x14);
+static_assert(offsetof(siginfo_t, si_status) == 0x18);
+static_assert(offsetof(siginfo_t, si_utime) == 0x20);
+static_assert(offsetof(siginfo_t, si_stime) == 0x28);
+
+#ifdef CONFIG_X86_X32_ABI
+/* no _sigchld_x32 in the generic siginfo_t */
+static_assert(sizeof_field(compat_siginfo_t, _sifields._sigchld_x32) ==
+ 7*sizeof(int));
+static_assert(offsetof(compat_siginfo_t, _sifields) ==
+ offsetof(compat_siginfo_t, _sifields._sigchld_x32));
+static_assert(offsetof(compat_siginfo_t, _sifields._sigchld_x32._utime) == 0x18);
+static_assert(offsetof(compat_siginfo_t, _sifields._sigchld_x32._stime) == 0x20);
+#endif
+
+CHECK_SI_OFFSET(_sigfault);
+CHECK_SI_SIZE (_sigfault, 8*sizeof(int));
+static_assert(offsetof(siginfo_t, si_addr) == 0x10);
+
+static_assert(offsetof(siginfo_t, si_trapno) == 0x18);
+
+static_assert(offsetof(siginfo_t, si_addr_lsb) == 0x18);
+
+static_assert(offsetof(siginfo_t, si_lower) == 0x20);
+static_assert(offsetof(siginfo_t, si_upper) == 0x28);
+
+static_assert(offsetof(siginfo_t, si_pkey) == 0x20);
+
+static_assert(offsetof(siginfo_t, si_perf_data) == 0x18);
+static_assert(offsetof(siginfo_t, si_perf_type) == 0x20);
+static_assert(offsetof(siginfo_t, si_perf_flags) == 0x24);
+
+CHECK_SI_OFFSET(_sigpoll);
+CHECK_SI_SIZE (_sigpoll, 4*sizeof(int));
+static_assert(offsetof(siginfo_t, si_band) == 0x10);
+static_assert(offsetof(siginfo_t, si_fd) == 0x18);
+
+CHECK_SI_OFFSET(_sigsys);
+CHECK_SI_SIZE (_sigsys, 4*sizeof(int));
+static_assert(offsetof(siginfo_t, si_call_addr) == 0x10);
+static_assert(offsetof(siginfo_t, si_syscall) == 0x18);
+static_assert(offsetof(siginfo_t, si_arch) == 0x1C);
+
+/* any new si_fields should be added here */