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| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2008-04-17 07:45:57 +0200 |
|---|---|---|
| committer | Heiko Carstens <heiko.carstens@de.ibm.com> | 2008-04-17 07:46:56 +0200 |
| commit | de553438eb6c487f72d46019eb3821f6687ce011 (patch) | |
| tree | 690fc48f89768c07dc0e338853ff7a93bac25a26 /arch/s390 | |
| parent | [S390] dasd: fix double elevator_exit call when deadline iosched fails to load (diff) | |
| download | linux-de553438eb6c487f72d46019eb3821f6687ce011.tar.xz linux-de553438eb6c487f72d46019eb3821f6687ce011.zip | |
[S390] Protect against sigaltstack wraparound.
This is just a port of 83bd01024b1fdfc41d9b758e5669e80fca72df66
"x86: protect against sigaltstack wraparound".
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/kernel/compat_signal.c | 10 | ||||
| -rw-r--r-- | arch/s390/kernel/signal.c | 10 |
2 files changed, 20 insertions, 0 deletions
diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c index a5692c460bad..ae2f2d313930 100644 --- a/arch/s390/kernel/compat_signal.c +++ b/arch/s390/kernel/compat_signal.c @@ -428,6 +428,10 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) /* Default to using normal stack */ sp = (unsigned long) A(regs->gprs[15]); + /* Overflow on alternate signal stack gives SIGSEGV. */ + if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL)) + return (void __user *) -1UL; + /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { if (! sas_ss_flags(sp)) @@ -461,6 +465,9 @@ static int setup_frame32(int sig, struct k_sigaction *ka, if (!access_ok(VERIFY_WRITE, frame, sizeof(sigframe32))) goto give_sigsegv; + if (frame == (void __user *) -1UL) + goto give_sigsegv; + if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE32)) goto give_sigsegv; @@ -514,6 +521,9 @@ static int setup_rt_frame32(int sig, struct k_sigaction *ka, siginfo_t *info, if (!access_ok(VERIFY_WRITE, frame, sizeof(rt_sigframe32))) goto give_sigsegv; + if (frame == (void __user *) -1UL) + goto give_sigsegv; + if (copy_siginfo_to_user32(&frame->info, info)) goto give_sigsegv; diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c index 4449bf32cbf1..8c92191949c2 100644 --- a/arch/s390/kernel/signal.c +++ b/arch/s390/kernel/signal.c @@ -235,6 +235,10 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) /* Default to using normal stack */ sp = regs->gprs[15]; + /* Overflow on alternate signal stack gives SIGSEGV. */ + if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL)) + return (void __user *) -1UL; + /* This is the X/Open sanctioned signal stack switching. */ if (ka->sa.sa_flags & SA_ONSTACK) { if (! sas_ss_flags(sp)) @@ -270,6 +274,9 @@ static int setup_frame(int sig, struct k_sigaction *ka, if (!access_ok(VERIFY_WRITE, frame, sizeof(sigframe))) goto give_sigsegv; + if (frame == (void __user *) -1UL) + goto give_sigsegv; + if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE)) goto give_sigsegv; @@ -327,6 +334,9 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, if (!access_ok(VERIFY_WRITE, frame, sizeof(rt_sigframe))) goto give_sigsegv; + if (frame == (void __user *) -1UL) + goto give_sigsegv; + if (copy_siginfo_to_user(&frame->info, info)) goto give_sigsegv; |