diff options
author | 2023-02-21 18:24:12 -0800 | |
---|---|---|
committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/sh/kernel/signal_32.c | |
download | linux-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/sh/kernel/signal_32.c')
-rw-r--r-- | arch/sh/kernel/signal_32.c | 507 |
1 files changed, 507 insertions, 0 deletions
diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c new file mode 100644 index 000000000..90f495d35 --- /dev/null +++ b/arch/sh/kernel/signal_32.c @@ -0,0 +1,507 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/arch/sh/kernel/signal.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * + * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson + * + * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima + * + */ +#include <linux/sched.h> +#include <linux/sched/task_stack.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/ptrace.h> +#include <linux/unistd.h> +#include <linux/stddef.h> +#include <linux/tty.h> +#include <linux/elf.h> +#include <linux/personality.h> +#include <linux/binfmts.h> +#include <linux/io.h> +#include <linux/resume_user_mode.h> +#include <asm/ucontext.h> +#include <linux/uaccess.h> +#include <asm/cacheflush.h> +#include <asm/syscalls.h> +#include <asm/fpu.h> + +struct fdpic_func_descriptor { + unsigned long text; + unsigned long GOT; +}; + +/* + * The following define adds a 64 byte gap between the signal + * stack frame and previous contents of the stack. This allows + * frame unwinding in a function epilogue but only if a frame + * pointer is used in the function. This is necessary because + * current gcc compilers (<4.3) do not generate unwind info on + * SH for function epilogues. + */ +#define UNWINDGUARD 64 + +/* + * Do a signal return; undo the signal stack. + */ + +#define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */ +#if defined(CONFIG_CPU_SH2) +#define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */ +#else +#define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */ +#endif +#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */ + +struct sigframe +{ + struct sigcontext sc; + unsigned long extramask[_NSIG_WORDS-1]; + u16 retcode[8]; +}; + +struct rt_sigframe +{ + struct siginfo info; + struct ucontext uc; + u16 retcode[8]; +}; + +#ifdef CONFIG_SH_FPU +static inline int restore_sigcontext_fpu(struct sigcontext __user *sc) +{ + struct task_struct *tsk = current; + + if (!(boot_cpu_data.flags & CPU_HAS_FPU)) + return 0; + + set_used_math(); + return __copy_from_user(&tsk->thread.xstate->hardfpu, &sc->sc_fpregs[0], + sizeof(long)*(16*2+2)); +} + +static inline int save_sigcontext_fpu(struct sigcontext __user *sc, + struct pt_regs *regs) +{ + struct task_struct *tsk = current; + + if (!(boot_cpu_data.flags & CPU_HAS_FPU)) + return 0; + + if (!used_math()) + return __put_user(0, &sc->sc_ownedfp); + + if (__put_user(1, &sc->sc_ownedfp)) + return -EFAULT; + + /* This will cause a "finit" to be triggered by the next + attempted FPU operation by the 'current' process. + */ + clear_used_math(); + + unlazy_fpu(tsk, regs); + return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.xstate->hardfpu, + sizeof(long)*(16*2+2)); +} +#endif /* CONFIG_SH_FPU */ + +static int +restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p) +{ + unsigned int err = 0; + +#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) + COPY(regs[1]); + COPY(regs[2]); COPY(regs[3]); + COPY(regs[4]); COPY(regs[5]); + COPY(regs[6]); COPY(regs[7]); + COPY(regs[8]); COPY(regs[9]); + COPY(regs[10]); COPY(regs[11]); + COPY(regs[12]); COPY(regs[13]); + COPY(regs[14]); COPY(regs[15]); + COPY(gbr); COPY(mach); + COPY(macl); COPY(pr); + COPY(sr); COPY(pc); +#undef COPY + +#ifdef CONFIG_SH_FPU + if (boot_cpu_data.flags & CPU_HAS_FPU) { + int owned_fp; + struct task_struct *tsk = current; + + regs->sr |= SR_FD; /* Release FPU */ + clear_fpu(tsk, regs); + clear_used_math(); + err |= __get_user (owned_fp, &sc->sc_ownedfp); + if (owned_fp) + err |= restore_sigcontext_fpu(sc); + } +#endif + + regs->tra = -1; /* disable syscall checks */ + err |= __get_user(*r0_p, &sc->sc_regs[0]); + return err; +} + +asmlinkage int sys_sigreturn(void) +{ + struct pt_regs *regs = current_pt_regs(); + struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15]; + sigset_t set; + int r0; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + if (!access_ok(frame, sizeof(*frame))) + goto badframe; + + if (__get_user(set.sig[0], &frame->sc.oldmask) + || (_NSIG_WORDS > 1 + && __copy_from_user(&set.sig[1], &frame->extramask, + sizeof(frame->extramask)))) + goto badframe; + + set_current_blocked(&set); + + if (restore_sigcontext(regs, &frame->sc, &r0)) + goto badframe; + return r0; + +badframe: + force_sig(SIGSEGV); + return 0; +} + +asmlinkage int sys_rt_sigreturn(void) +{ + struct pt_regs *regs = current_pt_regs(); + struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15]; + sigset_t set; + int r0; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + if (!access_ok(frame, sizeof(*frame))) + goto badframe; + + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) + goto badframe; + + set_current_blocked(&set); + + if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0)) + goto badframe; + + if (restore_altstack(&frame->uc.uc_stack)) + goto badframe; + + return r0; + +badframe: + force_sig(SIGSEGV); + return 0; +} + +/* + * Set up a signal frame. + */ + +static int +setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, + unsigned long mask) +{ + int err = 0; + +#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x) + COPY(regs[0]); COPY(regs[1]); + COPY(regs[2]); COPY(regs[3]); + COPY(regs[4]); COPY(regs[5]); + COPY(regs[6]); COPY(regs[7]); + COPY(regs[8]); COPY(regs[9]); + COPY(regs[10]); COPY(regs[11]); + COPY(regs[12]); COPY(regs[13]); + COPY(regs[14]); COPY(regs[15]); + COPY(gbr); COPY(mach); + COPY(macl); COPY(pr); + COPY(sr); COPY(pc); +#undef COPY + +#ifdef CONFIG_SH_FPU + err |= save_sigcontext_fpu(sc, regs); +#endif + + /* non-iBCS2 extensions.. */ + err |= __put_user(mask, &sc->oldmask); + + return err; +} + +/* + * Determine which stack to use.. + */ +static inline void __user * +get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) +{ + if (ka->sa.sa_flags & SA_ONSTACK) { + if (sas_ss_flags(sp) == 0) + sp = current->sas_ss_sp + current->sas_ss_size; + } + + return (void __user *)((sp - (frame_size+UNWINDGUARD)) & -8ul); +} + +/* These symbols are defined with the addresses in the vsyscall page. + See vsyscall-trapa.S. */ +extern void __kernel_sigreturn(void); +extern void __kernel_rt_sigreturn(void); + +static int setup_frame(struct ksignal *ksig, sigset_t *set, + struct pt_regs *regs) +{ + struct sigframe __user *frame; + int err = 0, sig = ksig->sig; + + frame = get_sigframe(&ksig->ka, regs->regs[15], sizeof(*frame)); + + if (!access_ok(frame, sizeof(*frame))) + return -EFAULT; + + err |= setup_sigcontext(&frame->sc, regs, set->sig[0]); + + if (_NSIG_WORDS > 1) + err |= __copy_to_user(frame->extramask, &set->sig[1], + sizeof(frame->extramask)); + + /* Set up to return from userspace. If provided, use a stub + already in userspace. */ + if (ksig->ka.sa.sa_flags & SA_RESTORER) { + regs->pr = (unsigned long) ksig->ka.sa.sa_restorer; +#ifdef CONFIG_VSYSCALL + } else if (likely(current->mm->context.vdso)) { + regs->pr = VDSO_SYM(&__kernel_sigreturn); +#endif + } else { + /* Generate return code (system call to sigreturn) */ + err |= __put_user(MOVW(7), &frame->retcode[0]); + err |= __put_user(TRAP_NOARG, &frame->retcode[1]); + err |= __put_user(OR_R0_R0, &frame->retcode[2]); + err |= __put_user(OR_R0_R0, &frame->retcode[3]); + err |= __put_user(OR_R0_R0, &frame->retcode[4]); + err |= __put_user(OR_R0_R0, &frame->retcode[5]); + err |= __put_user(OR_R0_R0, &frame->retcode[6]); + err |= __put_user((__NR_sigreturn), &frame->retcode[7]); + regs->pr = (unsigned long) frame->retcode; + flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode)); + } + + if (err) + return -EFAULT; + + /* Set up registers for signal handler */ + regs->regs[15] = (unsigned long) frame; + regs->regs[4] = sig; /* Arg for signal handler */ + regs->regs[5] = 0; + regs->regs[6] = (unsigned long) &frame->sc; + + if (current->personality & FDPIC_FUNCPTRS) { + struct fdpic_func_descriptor __user *funcptr = + (struct fdpic_func_descriptor __user *)ksig->ka.sa.sa_handler; + + err |= __get_user(regs->pc, &funcptr->text); + err |= __get_user(regs->regs[12], &funcptr->GOT); + } else + regs->pc = (unsigned long)ksig->ka.sa.sa_handler; + + if (err) + return -EFAULT; + + pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", + current->comm, task_pid_nr(current), frame, regs->pc, regs->pr); + + return 0; +} + +static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, + struct pt_regs *regs) +{ + struct rt_sigframe __user *frame; + int err = 0, sig = ksig->sig; + + frame = get_sigframe(&ksig->ka, regs->regs[15], sizeof(*frame)); + + if (!access_ok(frame, sizeof(*frame))) + return -EFAULT; + + err |= copy_siginfo_to_user(&frame->info, &ksig->info); + + /* Create the ucontext. */ + err |= __put_user(0, &frame->uc.uc_flags); + err |= __put_user(NULL, &frame->uc.uc_link); + err |= __save_altstack(&frame->uc.uc_stack, regs->regs[15]); + err |= setup_sigcontext(&frame->uc.uc_mcontext, + regs, set->sig[0]); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + + /* Set up to return from userspace. If provided, use a stub + already in userspace. */ + if (ksig->ka.sa.sa_flags & SA_RESTORER) { + regs->pr = (unsigned long) ksig->ka.sa.sa_restorer; +#ifdef CONFIG_VSYSCALL + } else if (likely(current->mm->context.vdso)) { + regs->pr = VDSO_SYM(&__kernel_rt_sigreturn); +#endif + } else { + /* Generate return code (system call to rt_sigreturn) */ + err |= __put_user(MOVW(7), &frame->retcode[0]); + err |= __put_user(TRAP_NOARG, &frame->retcode[1]); + err |= __put_user(OR_R0_R0, &frame->retcode[2]); + err |= __put_user(OR_R0_R0, &frame->retcode[3]); + err |= __put_user(OR_R0_R0, &frame->retcode[4]); + err |= __put_user(OR_R0_R0, &frame->retcode[5]); + err |= __put_user(OR_R0_R0, &frame->retcode[6]); + err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]); + regs->pr = (unsigned long) frame->retcode; + flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode)); + } + + if (err) + return -EFAULT; + + /* Set up registers for signal handler */ + regs->regs[15] = (unsigned long) frame; + regs->regs[4] = sig; /* Arg for signal handler */ + regs->regs[5] = (unsigned long) &frame->info; + regs->regs[6] = (unsigned long) &frame->uc; + + if (current->personality & FDPIC_FUNCPTRS) { + struct fdpic_func_descriptor __user *funcptr = + (struct fdpic_func_descriptor __user *)ksig->ka.sa.sa_handler; + + err |= __get_user(regs->pc, &funcptr->text); + err |= __get_user(regs->regs[12], &funcptr->GOT); + } else + regs->pc = (unsigned long)ksig->ka.sa.sa_handler; + + if (err) + return -EFAULT; + + pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", + current->comm, task_pid_nr(current), frame, regs->pc, regs->pr); + + return 0; +} + +static inline void +handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs, + struct sigaction *sa) +{ + /* If we're not from a syscall, bail out */ + if (regs->tra < 0) + return; + + /* check for system call restart.. */ + switch (regs->regs[0]) { + case -ERESTART_RESTARTBLOCK: + case -ERESTARTNOHAND: + no_system_call_restart: + regs->regs[0] = -EINTR; + break; + + case -ERESTARTSYS: + if (!(sa->sa_flags & SA_RESTART)) + goto no_system_call_restart; + fallthrough; + case -ERESTARTNOINTR: + regs->regs[0] = save_r0; + regs->pc -= instruction_size(__raw_readw(regs->pc - 4)); + break; + } +} + +/* + * OK, we're invoking a handler + */ +static void +handle_signal(struct ksignal *ksig, struct pt_regs *regs, unsigned int save_r0) +{ + sigset_t *oldset = sigmask_to_save(); + int ret; + + /* Set up the stack frame */ + if (ksig->ka.sa.sa_flags & SA_SIGINFO) + ret = setup_rt_frame(ksig, oldset, regs); + else + ret = setup_frame(ksig, oldset, regs); + + signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP)); +} + +/* + * Note that 'init' is a special process: it doesn't get signals it doesn't + * want to handle. Thus you cannot kill init even with a SIGKILL even by + * mistake. + * + * Note that we go through the signals twice: once to check the signals that + * the kernel can handle, and then we build all the user-level signal handling + * stack-frames in one go after that. + */ +static void do_signal(struct pt_regs *regs, unsigned int save_r0) +{ + struct ksignal ksig; + + /* + * We want the common case to go fast, which + * is why we may in certain cases get here from + * kernel mode. Just return without doing anything + * if so. + */ + if (!user_mode(regs)) + return; + + if (get_signal(&ksig)) { + handle_syscall_restart(save_r0, regs, &ksig.ka.sa); + + /* Whee! Actually deliver the signal. */ + handle_signal(&ksig, regs, save_r0); + return; + } + + /* Did we come from a system call? */ + if (regs->tra >= 0) { + /* Restart the system call - no handlers present */ + if (regs->regs[0] == -ERESTARTNOHAND || + regs->regs[0] == -ERESTARTSYS || + regs->regs[0] == -ERESTARTNOINTR) { + regs->regs[0] = save_r0; + regs->pc -= instruction_size(__raw_readw(regs->pc - 4)); + } else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) { + regs->pc -= instruction_size(__raw_readw(regs->pc - 4)); + regs->regs[3] = __NR_restart_syscall; + } + } + + /* + * If there's no signal to deliver, we just put the saved sigmask + * back. + */ + restore_saved_sigmask(); +} + +asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0, + unsigned long thread_info_flags) +{ + /* deal with pending signal delivery */ + if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) + do_signal(regs, save_r0); + + if (thread_info_flags & _TIF_NOTIFY_RESUME) + resume_user_mode_work(regs); +} |