commit a350f216b30c5841b8eb0303c9c3fd32a2b2245b Author: Daniel Pinto danielpinto52@gmail.com Date: Tue Apr 17 01:31:49 2018 +0100

Fix crash when calling openat with sandbox enabled #25440

The seccomp rule for the openat syscall checks for the AT_FDCWD constant. Because this constant is usually a negative value, a cast to unsigned int is necessary to make sure it does not get converted to uint64_t used by seccomp.

More info on: https://github.com/seccomp/libseccomp/issues/69#issuecomment-273805980 --- src/common/sandbox.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/common/sandbox.c b/src/common/sandbox.c index 3d27ea66b..0a972d496 100644 --- a/src/common/sandbox.c +++ b/src/common/sandbox.c @@ -469,7 +469,7 @@ allow_file_open(scmp_filter_ctx ctx, int use_openat, const char *file) { if (use_openat) { return seccomp_rule_add_2(ctx, SCMP_ACT_ALLOW, SCMP_SYS(openat), - SCMP_CMP_STR(0, SCMP_CMP_EQ, AT_FDCWD), + SCMP_CMP(0, SCMP_CMP_EQ, (unsigned int)AT_FDCWD), SCMP_CMP_STR(1, SCMP_CMP_EQ, file)); } else { return seccomp_rule_add_1(ctx, SCMP_ACT_ALLOW, SCMP_SYS(open),