diff options
| -rw-r--r-- | fs/fcntl.c | 13 | ||||
| -rw-r--r-- | include/linux/signal.h | 8 | ||||
| -rw-r--r-- | include/uapi/asm-generic/siginfo.h | 4 |
3 files changed, 22 insertions, 3 deletions
diff --git a/fs/fcntl.c b/fs/fcntl.c index 3b01b646e528..0491da3b28c3 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -741,10 +741,21 @@ static void send_sigio_to_task(struct task_struct *p, si.si_signo = signum; si.si_errno = 0; si.si_code = reason; + /* + * Posix definies POLL_IN and friends to be signal + * specific si_codes for SIG_POLL. Linux extended + * these si_codes to other signals in a way that is + * ambiguous if other signals also have signal + * specific si_codes. In that case use SI_SIGIO instead + * to remove the ambiguity. + */ + if (sig_specific_sicodes(signum)) + si.si_code = SI_SIGIO; + /* Make sure we are called with one of the POLL_* reasons, otherwise we could leak kernel stack into userspace. */ - BUG_ON((reason & __SI_MASK) != __SI_POLL); + BUG_ON((reason < POLL_IN) || ((reason - POLL_IN) >= NSIGPOLL)); if (reason - POLL_IN >= NSIGPOLL) si.si_band = ~0L; else diff --git a/include/linux/signal.h b/include/linux/signal.h index e2678b5dbb21..c97cc20369c0 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -380,10 +380,18 @@ int unhandled_signal(struct task_struct *tsk, int sig); rt_sigmask(SIGCONT) | rt_sigmask(SIGCHLD) | \ rt_sigmask(SIGWINCH) | rt_sigmask(SIGURG) ) +#define SIG_SPECIFIC_SICODES_MASK (\ + rt_sigmask(SIGILL) | rt_sigmask(SIGFPE) | \ + rt_sigmask(SIGSEGV) | rt_sigmask(SIGBUS) | \ + rt_sigmask(SIGTRAP) | rt_sigmask(SIGCHLD) | \ + rt_sigmask(SIGPOLL) | rt_sigmask(SIGSYS) | \ + SIGEMT_MASK ) + #define sig_kernel_only(sig) siginmask(sig, SIG_KERNEL_ONLY_MASK) #define sig_kernel_coredump(sig) siginmask(sig, SIG_KERNEL_COREDUMP_MASK) #define sig_kernel_ignore(sig) siginmask(sig, SIG_KERNEL_IGNORE_MASK) #define sig_kernel_stop(sig) siginmask(sig, SIG_KERNEL_STOP_MASK) +#define sig_specific_sicodes(sig) siginmask(sig, SIG_SPECIFIC_SICODES_MASK) #define sig_fatal(t, signr) \ (!siginmask(signr, SIG_KERNEL_IGNORE_MASK|SIG_KERNEL_STOP_MASK) && \ diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h index 9c4eca6b374a..9e956ea94d57 100644 --- a/include/uapi/asm-generic/siginfo.h +++ b/include/uapi/asm-generic/siginfo.h @@ -184,7 +184,7 @@ typedef struct siginfo { #define SI_TIMER __SI_CODE(__SI_TIMER,-2) /* sent by timer expiration */ #define SI_MESGQ __SI_CODE(__SI_MESGQ,-3) /* sent by real time mesq state change */ #define SI_ASYNCIO -4 /* sent by AIO completion */ -#define SI_SIGIO -5 /* sent by queued SIGIO */ +#define SI_SIGIO __SI_CODE(__SI_POLL,-5) /* sent by queued SIGIO */ #define SI_TKILL -6 /* sent by tkill system call */ #define SI_DETHREAD -7 /* sent by execve() killing subsidiary threads */ @@ -259,7 +259,7 @@ typedef struct siginfo { #define NSIGCHLD 6 /* - * SIGPOLL si_codes + * SIGPOLL (or any other signal without signal specific si_codes) si_codes */ #define POLL_IN (__SI_POLL|1) /* data input available */ #define POLL_OUT (__SI_POLL|2) /* output buffers available */ |