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| author | kib <kib@FreeBSD.org> | 2009-10-27 10:47:58 +0000 |
|---|---|---|
| committer | kib <kib@FreeBSD.org> | 2009-10-27 10:47:58 +0000 |
| commit | ce081b037e7a762f0dd090a207cafc5121f39f51 (patch) | |
| tree | 359a5b0885ae5a789f55ba40dc485621e67c34b1 /sys/i386/linux/linux_sysvec.c | |
| parent | eb4c68098b66d84de3abc7be00acfdc6d2f8f980 (diff) | |
| download | FreeBSD-src-ce081b037e7a762f0dd090a207cafc5121f39f51.zip FreeBSD-src-ce081b037e7a762f0dd090a207cafc5121f39f51.tar.gz | |
In r197963, a race with thread being selected for signal delivery
while in kernel mode, and later changing signal mask to block the
signal, was fixed for sigprocmask(2) and ptread_exit(3). The same race
exists for sigreturn(2), setcontext(2) and swapcontext(2) syscalls.
Use kern_sigprocmask() instead of direct manipulation of td_sigmask to
reschedule newly blocked signals, closing the race.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
Diffstat (limited to 'sys/i386/linux/linux_sysvec.c')
| -rw-r--r-- | sys/i386/linux/linux_sysvec.c | 18 |
1 files changed, 6 insertions, 12 deletions
diff --git a/sys/i386/linux/linux_sysvec.c b/sys/i386/linux/linux_sysvec.c index d07f655..069b5bb 100644 --- a/sys/i386/linux/linux_sysvec.c +++ b/sys/i386/linux/linux_sysvec.c @@ -667,10 +667,10 @@ linux_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) int linux_sigreturn(struct thread *td, struct linux_sigreturn_args *args) { - struct proc *p = td->td_proc; struct l_sigframe frame; struct trapframe *regs; l_sigset_t lmask; + sigset_t bmask; int eflags, i; ksiginfo_t ksi; @@ -725,11 +725,8 @@ linux_sigreturn(struct thread *td, struct linux_sigreturn_args *args) lmask.__bits[0] = frame.sf_sc.sc_mask; for (i = 0; i < (LINUX_NSIG_WORDS-1); i++) lmask.__bits[i+1] = frame.sf_extramask[i]; - PROC_LOCK(p); - linux_to_bsd_sigset(&lmask, &td->td_sigmask); - SIG_CANTMASK(td->td_sigmask); - signotify(td); - PROC_UNLOCK(p); + linux_to_bsd_sigset(&lmask, &bmask); + kern_sigprocmask(td, SIG_SETMASK, &bmask, NULL, 0); /* * Restore signal context. @@ -767,9 +764,9 @@ linux_sigreturn(struct thread *td, struct linux_sigreturn_args *args) int linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) { - struct proc *p = td->td_proc; struct l_ucontext uc; struct l_sigcontext *context; + sigset_t bmask; l_stack_t *lss; stack_t ss; struct trapframe *regs; @@ -826,11 +823,8 @@ linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) return(EINVAL); } - PROC_LOCK(p); - linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); - SIG_CANTMASK(td->td_sigmask); - signotify(td); - PROC_UNLOCK(p); + linux_to_bsd_sigset(&uc.uc_sigmask, &bmask); + kern_sigprocmask(td, SIG_SETMASK, &bmask, NULL, 0); /* * Restore signal context |
