diff options
| author | Kees Cook <keescook@chromium.org> | 2015-02-17 13:48:00 -0800 |
|---|---|---|
| committer | Mister Oyster <oysterized@gmail.com> | 2017-04-11 10:57:25 +0200 |
| commit | fcfc0b5d6c20972ab9198780d38a3a8c86de0408 (patch) | |
| tree | e52284659172b46104eb767a4cfea373956ae275 /kernel | |
| parent | a27766976672ba5e41519ea75503564912bb68b7 (diff) | |
UPSTREAM: seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO
The value resulting from the SECCOMP_RET_DATA mask could exceed MAX_ERRNO
when setting errno during a SECCOMP_RET_ERRNO filter action. This makes
sure we have a reliable value being set, so that an invalid errno will not
be ignored by userspace.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Dmitry V. Levin <ldv@altlinux.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 580c57f1076872ebc2427f898b927944ce170f2d)
Signed-off-by: Kees Cook <keescook@google.com>
Change-Id: If82aa1b5f4be6375e8ca301d317d3d2db88a66dd
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/seccomp.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 1fbb1a2bc..e9eff38dc 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -600,7 +600,9 @@ int __secure_computing(int this_syscall) ret &= SECCOMP_RET_ACTION; switch (ret) { case SECCOMP_RET_ERRNO: - /* Set the low-order 16-bits as a errno. */ + /* Set low-order bits as an errno, capped at MAX_ERRNO. */ + if (data > MAX_ERRNO) + data = MAX_ERRNO; syscall_set_return_value(current, regs, -data, 0); goto skip; |