diff options
Diffstat (limited to 'fs/fcntl.c')
| -rw-r--r-- | fs/fcntl.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/fs/fcntl.c b/fs/fcntl.c index 3b01b646e528..8d78ffd7b399 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/fcntl.c * @@ -741,10 +742,21 @@ 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 ((signum != SIGPOLL) && 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 |