| From 398d2ceef92cb1baac18e6b34a1a8e1bf41296cd Mon Sep 17 00:00:00 2001 |
| From: Nicolas Iooss <nicolas.iooss@m4x.org> |
| Date: Tue, 16 Feb 2021 22:13:28 +0100 |
| Subject: [PATCH] libselinux: rename gettid() to something which never |
| conflicts with the libc |
| |
| Musl recently added a wrapper for gettid() syscall. There is no way to |
| detect this new version in a reliable way, so rename our gettid() |
| wrapper to a non-conflicting name. |
| |
| Introduce a new function which, when using a libc known to provide a |
| wrapper for gettid(), calls it, and which, otherwise, performs the |
| syscall directly. |
| |
| Anyway this function is only used on systems where /proc/thread-self |
| does not exist, which are therefore running Linux<3.17. |
| |
| Fixes: https://github.com/SELinuxProject/selinux/issues/282 |
| Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org> |
| Acked-by: Petr Lautrbach <plautrba@redhat.com> |
| [Retrieved from: |
| https://github.com/SELinuxProject/selinux/commit/398d2ceef92cb1baac18e6b34a1a8e1bf41296cd] |
| Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com> |
| --- |
| src/procattr.c | 18 ++++++++++-------- |
| 1 file changed, 10 insertions(+), 8 deletions(-) |
| |
| diff --git a/src/procattr.c b/src/procattr.c |
| index 1aa67ac53..840570525 100644 |
| --- a/src/procattr.c |
| +++ b/src/procattr.c |
| @@ -25,21 +25,23 @@ static __thread char destructor_initialized; |
| /* Bionic and glibc >= 2.30 declare gettid() system call wrapper in unistd.h and |
| * has a definition for it */ |
| #ifdef __BIONIC__ |
| - #define OVERRIDE_GETTID 0 |
| + #define HAVE_GETTID 1 |
| #elif !defined(__GLIBC_PREREQ) |
| - #define OVERRIDE_GETTID 1 |
| + #define HAVE_GETTID 0 |
| #elif !__GLIBC_PREREQ(2,30) |
| - #define OVERRIDE_GETTID 1 |
| + #define HAVE_GETTID 0 |
| #else |
| - #define OVERRIDE_GETTID 0 |
| + #define HAVE_GETTID 1 |
| #endif |
| |
| -#if OVERRIDE_GETTID |
| -static pid_t gettid(void) |
| +static pid_t selinux_gettid(void) |
| { |
| +#if HAVE_GETTID |
| + return gettid(); |
| +#else |
| return syscall(__NR_gettid); |
| -} |
| #endif |
| +} |
| |
| static void procattr_thread_destructor(void __attribute__((unused)) *unused) |
| { |
| @@ -94,7 +96,7 @@ static int openattr(pid_t pid, const char *attr, int flags) |
| if (fd >= 0 || errno != ENOENT) |
| goto out; |
| free(path); |
| - tid = gettid(); |
| + tid = selinux_gettid(); |
| rc = asprintf(&path, "/proc/self/task/%d/attr/%s", tid, attr); |
| } else { |
| errno = EINVAL; |