diff options
| -rw-r--r-- | .topdeps | 3 | ||||
| -rw-r--r-- | .topmsg | 14 | ||||
| -rw-r--r-- | sysdeps/mach/hurd/i386/sigreturn.c | 68 |
3 files changed, 50 insertions, 35 deletions
@@ -1 +1,2 @@ -t/tls +t/tls-threadvar +t/hurdsig-global-dispositions @@ -1,9 +1,7 @@ -COMMITED +From: Samuel Thibault <samuel.thibault@ens-lyon.org> +Subject: [PATCH] Fix SS_ONSTACK support -From: Thomas Schwinge <thomas@schwinge.name> -Subject: [PATCH] tls-threadvar - -replace the custom threadvar mechanism with generic TLS. -That will fix sigaltstack. - -Note: the added reply_port and _hurd_sigstate fields should be kept last. +* sysdeps/mach/hurd/i386/sigreturn.c (__sigreturn2): New function, +unlocks SS and returns to the saved PC. +(__sigreturn): Do not unlock SS, and "return" into __sigreturn2 on the +thread stack instead of the saved PC. diff --git a/sysdeps/mach/hurd/i386/sigreturn.c b/sysdeps/mach/hurd/i386/sigreturn.c index 4462b5e792..9a61854c9a 100644 --- a/sysdeps/mach/hurd/i386/sigreturn.c +++ b/sysdeps/mach/hurd/i386/sigreturn.c @@ -24,6 +24,36 @@ register int *sp asm ("%esp"); #include <stdlib.h> #include <string.h> +/* This is run on the thread stack after restoring it, to be able to + unlock SS off sigstack. */ +static void +__sigreturn2 (int *usp) +{ + struct hurd_sigstate *ss = _hurd_self_sigstate (); + _hurd_sigstate_unlock (ss); + + sp = usp; +#define A(line) asm volatile (#line) + /* The members in the sigcontext are arranged in this order + so we can pop them easily. */ + + /* Pop the segment registers (except %cs and %ss, done last). */ + A (popl %gs); + A (popl %fs); + A (popl %es); + A (popl %ds); + /* Pop the general registers. */ + A (popa); + /* Pop the processor flags. */ + A (popf); + /* Return to the saved PC. */ + A (ret); + + /* Firewall. */ + A (hlt); +#undef A +} + int __sigreturn (struct sigcontext *scp) { @@ -67,13 +97,7 @@ __sigreturn (struct sigcontext *scp) } if (scp->sc_onstack) - { - ss->sigaltstack.ss_flags &= ~SS_ONSTACK; - /* XXX cannot unlock until off sigstack */ - abort (); - } - else - _hurd_sigstate_unlock (ss); + ss->sigaltstack.ss_flags &= ~SS_ONSTACK; /* Destroy the MiG reply port used by the signal handler, and restore the reply port in use by the thread when interrupted. */ @@ -108,27 +132,19 @@ __sigreturn (struct sigcontext *scp) *--usp = scp->sc_efl; memcpy (usp -= 12, &scp->sc_i386_thread_state, 12 * sizeof (int)); - sp = usp; - -#define A(line) asm volatile (#line) - /* The members in the sigcontext are arranged in this order - so we can pop them easily. */ - - /* Pop the segment registers (except %cs and %ss, done last). */ - A (popl %gs); - A (popl %fs); - A (popl %es); - A (popl %ds); - /* Pop the general registers. */ - A (popa); - /* Pop the processor flags. */ - A (popf); - /* Return to the saved PC. */ - A (ret); + /* Pass usp to __sigreturn2 so it can unwind itself easily. */ + *(usp-1) = (int) usp; + --usp; + /* Bogus return address for __sigreturn2 */ + *--usp = 0; + *--usp = (int) __sigreturn2; + /* Restore thread stack */ + sp = usp; + /* Return into __sigreturn2. */ + asm volatile ("ret"); /* Firewall. */ - A (hlt); -#undef A + asm volatile ("hlt"); } /* NOTREACHED */ |