Commit-ID: f01703b3d2e6faf7233cedf78f1e2d31b39fa90f Gitweb: https://git.kernel.org/tip/f01703b3d2e6faf7233cedf78f1e2d31b39fa90f Author: Vincenzo Frascino <[email protected]> AuthorDate: Fri, 21 Jun 2019 10:52:41 +0100 Committer: Thomas Gleixner <[email protected]> CommitDate: Sat, 22 Jun 2019 21:21:09 +0200
arm64: compat: Get sigreturn trampolines from vDSO When the compat vDSO is enabled, the sigreturn trampolines are not anymore available through [sigpage] but through [vdso]. Add the relevant code the enable the feature. Signed-off-by: Vincenzo Frascino <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Shijith Thotton <[email protected]> Tested-by: Andre Przywara <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Russell King <[email protected]> Cc: Ralf Baechle <[email protected]> Cc: Paul Burton <[email protected]> Cc: Daniel Lezcano <[email protected]> Cc: Mark Salyzyn <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Dmitry Safonov <[email protected]> Cc: Rasmus Villemoes <[email protected]> Cc: Huw Davies <[email protected]> Link: https://lkml.kernel.org/r/[email protected] --- arch/arm64/include/asm/vdso.h | 3 +++ arch/arm64/kernel/signal32.c | 26 ++++++++++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/arch/arm64/include/asm/vdso.h b/arch/arm64/include/asm/vdso.h index 1f94ec19903c..9c15e0a06301 100644 --- a/arch/arm64/include/asm/vdso.h +++ b/arch/arm64/include/asm/vdso.h @@ -17,6 +17,9 @@ #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 8a9a5ceb63b7..12a585386c2f 100644 --- a/arch/arm64/kernel/signal32.c +++ b/arch/arm64/kernel/signal32.c @@ -18,6 +18,7 @@ #include <asm/traps.h> #include <linux/uaccess.h> #include <asm/unistd.h> +#include <asm/vdso.h> struct compat_vfp_sigframe { compat_ulong_t magic; @@ -341,6 +342,30 @@ 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; if (ka->sa.sa_flags & SA_SIGINFO) @@ -348,6 +373,7 @@ static void compat_setup_return(struct pt_regs *regs, struct k_sigaction *ka, retcode = (unsigned long)current->mm->context.vdso + (idx << 2) + thumb; +#endif } regs->regs[0] = usig;

