[PATCH 20/27] arm64: compat: Get sigreturn trampolines from vDSO
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STALE2879d
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From: vincenzo.frascino@arm.com (Vincenzo Frascino)
Date: 2018-11-09 12:37:23
Also in:
linux-arch
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
Revision v1 of 6 in this series.
Revisions (6)
When the compat vDSO is enabled, the sigreturn trampolines are not anymore available through [sigpage] but through [vdso]. This patch adds the relevant code the enable the feature. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <redacted> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> --- arch/arm64/include/asm/vdso.h | 3 +++ arch/arm64/kernel/signal32.c | 29 +++++++++++++++++++++++++++-- 2 files changed, 30 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/include/asm/vdso.h b/arch/arm64/include/asm/vdso.h
index 839ce0031bd5..9b197e5ea759 100644
--- a/arch/arm64/include/asm/vdso.h
+++ b/arch/arm64/include/asm/vdso.h@@ -28,6 +28,9 @@ #ifndef __ASSEMBLY__ #include <generated/vdso-offsets.h> +#ifdef CONFIG_COMPAT_VDSO +#include <generated/vdso32-offsets.h> +#endif #define VDSO_SYMBOL(base, name) \ ({ \
diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c
index 16c490a83131..be471a81084e 100644
--- a/arch/arm64/kernel/signal32.c
+++ b/arch/arm64/kernel/signal32.c@@ -29,6 +29,7 @@ #include <asm/traps.h> #include <linux/uaccess.h> #include <asm/unistd.h> +#include <asm/vdso.h> struct compat_vfp_sigframe { compat_ulong_t magic;
@@ -333,7 +334,6 @@ static void compat_setup_return(struct pt_regs *regs, struct k_sigaction *ka, compat_ulong_t retcode; compat_ulong_t spsr = regs->pstate & ~(PSR_f | PSR_AA32_E_BIT); int thumb; - void *sigreturn_base; /* Check if the handler is written for ARM or Thumb */ thumb = handler & 1;
@@ -353,14 +353,39 @@ static void compat_setup_return(struct pt_regs *regs, struct k_sigaction *ka, retcode = ptr_to_compat(ka->sa.sa_restorer); } else { /* Set up sigreturn pointer */ +#ifdef CONFIG_COMPAT_VDSO + void *vdso_base = current->mm->context.vdso; + void *vdso_trampoline; + + if (ka->sa.sa_flags & SA_SIGINFO) { + if (thumb) { + vdso_trampoline = VDSO_SYMBOL(vdso_base, + compat_rt_sigreturn_thumb); + } else { + vdso_trampoline = VDSO_SYMBOL(vdso_base, + compat_rt_sigreturn_arm); + } + } else { + if (thumb) { + vdso_trampoline = VDSO_SYMBOL(vdso_base, + compat_sigreturn_thumb); + } else { + vdso_trampoline = VDSO_SYMBOL(vdso_base, + compat_sigreturn_arm); + } + } + + retcode = ptr_to_compat(vdso_trampoline) + thumb; +#else unsigned int idx = thumb << 1; - sigreturn_base = current->mm->context.vdso; + void *sigreturn_base = current->mm->context.vdso; if (ka->sa.sa_flags & SA_SIGINFO) idx += 3; retcode = ptr_to_compat(sigreturn_base) + (idx << 2) + thumb; +#endif } regs->regs[0] = usig;
--
2.19.1