From: Laurent MEYER - When setting a sighandler using sigaction() call, if the flag SA_ONSTACK is set and no alternate stack is provided via sigaltstack(), the kernel still try to install the alternate stack. This behavior is the opposite of the one which is documented in Single Unix Specifications V3. - Also when setting an alternate stack using sigaltstack() with the flag SS_DISABLE, the kernel try to install the alternate stack on signal delivery. These two use cases makes the process crash at signal delivery. [akpm: untested at time of submission] Signed-off-by: Laurent Meyer Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: David Howells Cc: Yoshinori Sato Cc: Geert Uytterhoeven Cc: Roman Zippel Cc: Kyle McMartin Cc: Paul Mundt Cc: Kazumoto Kojima Cc: Chris Zankel Signed-off-by: Andrew Morton --- arch/alpha/kernel/signal.c | 2 +- arch/frv/kernel/signal.c | 2 +- arch/h8300/kernel/signal.c | 2 +- arch/m68k/kernel/signal.c | 2 +- arch/m68knommu/kernel/signal.c | 2 +- arch/parisc/kernel/signal.c | 2 +- arch/sh64/kernel/signal.c | 2 +- arch/v850/kernel/signal.c | 2 +- arch/xtensa/kernel/signal.c | 2 +- 9 files changed, 9 insertions(+), 9 deletions(-) diff -puN arch/alpha/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/alpha/kernel/signal.c --- 25/arch/alpha/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/alpha/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -375,7 +375,7 @@ give_sigsegv: static inline void __user * get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) { - if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp)) + if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) sp = current->sas_ss_sp + current->sas_ss_size; return (void __user *)((sp - frame_size) & -32ul); diff -puN arch/frv/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/frv/kernel/signal.c --- 25/arch/frv/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/frv/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -233,7 +233,7 @@ static inline void __user *get_sigframe( /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { - if (! on_sig_stack(sp)) + if (! sas_ss_flags(sp)) sp = current->sas_ss_sp + current->sas_ss_size; } diff -puN arch/h8300/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/h8300/kernel/signal.c --- 25/arch/h8300/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/h8300/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -307,7 +307,7 @@ get_sigframe(struct k_sigaction *ka, str /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { - if (!on_sig_stack(usp)) + if (!sas_ss_flags(usp)) usp = current->sas_ss_sp + current->sas_ss_size; } return (void *)((usp - frame_size) & -8UL); diff -puN arch/m68k/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/m68k/kernel/signal.c --- 25/arch/m68k/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/m68k/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -763,7 +763,7 @@ get_sigframe(struct k_sigaction *ka, str /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { - if (!on_sig_stack(usp)) + if (!sas_ss_flags(usp)) usp = current->sas_ss_sp + current->sas_ss_size; } return (void __user *)((usp - frame_size) & -8UL); diff -puN arch/m68knommu/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/m68knommu/kernel/signal.c --- 25/arch/m68knommu/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/m68knommu/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -553,7 +553,7 @@ get_sigframe(struct k_sigaction *ka, str /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { - if (!on_sig_stack(usp)) + if (!sas_ss_flags(usp)) usp = current->sas_ss_sp + current->sas_ss_size; } return (void *)((usp - frame_size) & -8UL); diff -puN arch/parisc/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/parisc/kernel/signal.c --- 25/arch/parisc/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/parisc/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -248,7 +248,7 @@ get_sigframe(struct k_sigaction *ka, uns DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n", (unsigned long)ka, sp, frame_size); - if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp)) + if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) sp = current->sas_ss_sp; /* Stacks grow up! */ DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp); diff -puN arch/sh64/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/sh64/kernel/signal.c --- 25/arch/sh64/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/sh64/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -407,7 +407,7 @@ setup_sigcontext(struct sigcontext __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) != 0 && ! on_sig_stack(sp)) + if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) sp = current->sas_ss_sp + current->sas_ss_size; return (void __user *)((sp - frame_size) & -8ul); diff -puN arch/v850/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/v850/kernel/signal.c --- 25/arch/v850/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/v850/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -274,7 +274,7 @@ get_sigframe(struct k_sigaction *ka, str /* Default to using normal stack */ unsigned long sp = regs->gpr[GPR_SP]; - if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp)) + if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) sp = current->sas_ss_sp + current->sas_ss_size; return (void *)((sp - frame_size) & -8UL); diff -puN arch/xtensa/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes arch/xtensa/kernel/signal.c --- 25/arch/xtensa/kernel/signal.c~fix-incorrect-sa_onstack-behaviour-for-64-bit-processes Mon Apr 24 14:42:50 2006 +++ 25-akpm/arch/xtensa/kernel/signal.c Mon Apr 24 14:42:50 2006 @@ -433,7 +433,7 @@ badframe: static inline void * get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) { - if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp)) + if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) sp = current->sas_ss_sp + current->sas_ss_size; return (void *)((sp - frame_size) & -16ul); _