| Message ID | 20241018151300.445618-1-cgoettsche@seltendoof.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/4] libselinux: avoid errno modification by fclose(3) | expand |
On Fri, Oct 18, 2024 at 11:13 AM Christian Göttsche <cgoettsche@seltendoof.de> wrote: > > From: Christian Göttsche <cgzones@googlemail.com> > > In case fclose(3) might modify the global variable errno, use a wrapper > retaining the errno value. In the affected cases the success of > fclose(3) itself is not important, since the underlying descriptor is > only read from. > > Reported-by: clang-analyzer > Signed-off-by: Christian Göttsche <cgzones@googlemail.com> For these four patches: Acked-by: James Carter <jwcart2@gmail.com> > --- > libselinux/src/get_context_list.c | 4 ++-- > libselinux/src/label_file.c | 4 ++-- > libselinux/src/selinux_internal.h | 11 +++++++++++ > 3 files changed, 15 insertions(+), 4 deletions(-) > > diff --git a/libselinux/src/get_context_list.c b/libselinux/src/get_context_list.c > index 0ad24654..222b54c1 100644 > --- a/libselinux/src/get_context_list.c > +++ b/libselinux/src/get_context_list.c > @@ -438,7 +438,7 @@ int get_ordered_context_list(const char *user, > __fsetlocking(fp, FSETLOCKING_BYCALLER); > rc = get_context_user(fp, con, user, &reachable, &nreachable); > > - fclose(fp); > + fclose_errno_safe(fp); > if (rc < 0 && errno != ENOENT) { > selinux_log(SELINUX_ERROR, > "%s: error in processing configuration file %s\n", > @@ -451,7 +451,7 @@ int get_ordered_context_list(const char *user, > if (fp) { > __fsetlocking(fp, FSETLOCKING_BYCALLER); > rc = get_context_user(fp, con, user, &reachable, &nreachable); > - fclose(fp); > + fclose_errno_safe(fp); > if (rc < 0 && errno != ENOENT) { > selinux_log(SELINUX_ERROR, > "%s: error in processing configuration file %s\n", > diff --git a/libselinux/src/label_file.c b/libselinux/src/label_file.c > index 2fad0c93..40628e2c 100644 > --- a/libselinux/src/label_file.c > +++ b/libselinux/src/label_file.c > @@ -628,7 +628,7 @@ static int process_file(const char *path, const char *suffix, > > rc = fcontext_is_binary(fp); > if (rc < 0) { > - (void) fclose(fp); > + fclose_errno_safe(fp); > return -1; > } > > @@ -639,7 +639,7 @@ static int process_file(const char *path, const char *suffix, > rc = digest_add_specfile(digest, fp, NULL, sb.st_size, > found_path); > > - fclose(fp); > + fclose_errno_safe(fp); > > if (!rc) > return 0; > diff --git a/libselinux/src/selinux_internal.h b/libselinux/src/selinux_internal.h > index 450a42c2..372837dd 100644 > --- a/libselinux/src/selinux_internal.h > +++ b/libselinux/src/selinux_internal.h > @@ -2,7 +2,9 @@ > #define SELINUX_INTERNAL_H_ > > #include <selinux/selinux.h> > +#include <errno.h> > #include <pthread.h> > +#include <stdio.h> > > > extern int require_seusers ; > @@ -131,4 +133,13 @@ void *reallocarray(void *ptr, size_t nmemb, size_t size); > #define IGNORE_DEPRECATED_DECLARATION_END > #endif > > +static inline void fclose_errno_safe(FILE *stream) > +{ > + int saved_errno; > + > + saved_errno = errno; > + (void) fclose(stream); > + errno = saved_errno; > +} > + > #endif /* SELINUX_INTERNAL_H_ */ > -- > 2.45.2 > >
diff --git a/libselinux/src/get_context_list.c b/libselinux/src/get_context_list.c index 0ad24654..222b54c1 100644 --- a/libselinux/src/get_context_list.c +++ b/libselinux/src/get_context_list.c @@ -438,7 +438,7 @@ int get_ordered_context_list(const char *user, __fsetlocking(fp, FSETLOCKING_BYCALLER); rc = get_context_user(fp, con, user, &reachable, &nreachable); - fclose(fp); + fclose_errno_safe(fp); if (rc < 0 && errno != ENOENT) { selinux_log(SELINUX_ERROR, "%s: error in processing configuration file %s\n", @@ -451,7 +451,7 @@ int get_ordered_context_list(const char *user, if (fp) { __fsetlocking(fp, FSETLOCKING_BYCALLER); rc = get_context_user(fp, con, user, &reachable, &nreachable); - fclose(fp); + fclose_errno_safe(fp); if (rc < 0 && errno != ENOENT) { selinux_log(SELINUX_ERROR, "%s: error in processing configuration file %s\n", diff --git a/libselinux/src/label_file.c b/libselinux/src/label_file.c index 2fad0c93..40628e2c 100644 --- a/libselinux/src/label_file.c +++ b/libselinux/src/label_file.c @@ -628,7 +628,7 @@ static int process_file(const char *path, const char *suffix, rc = fcontext_is_binary(fp); if (rc < 0) { - (void) fclose(fp); + fclose_errno_safe(fp); return -1; } @@ -639,7 +639,7 @@ static int process_file(const char *path, const char *suffix, rc = digest_add_specfile(digest, fp, NULL, sb.st_size, found_path); - fclose(fp); + fclose_errno_safe(fp); if (!rc) return 0; diff --git a/libselinux/src/selinux_internal.h b/libselinux/src/selinux_internal.h index 450a42c2..372837dd 100644 --- a/libselinux/src/selinux_internal.h +++ b/libselinux/src/selinux_internal.h @@ -2,7 +2,9 @@ #define SELINUX_INTERNAL_H_ #include <selinux/selinux.h> +#include <errno.h> #include <pthread.h> +#include <stdio.h> extern int require_seusers ; @@ -131,4 +133,13 @@ void *reallocarray(void *ptr, size_t nmemb, size_t size); #define IGNORE_DEPRECATED_DECLARATION_END #endif +static inline void fclose_errno_safe(FILE *stream) +{ + int saved_errno; + + saved_errno = errno; + (void) fclose(stream); + errno = saved_errno; +} + #endif /* SELINUX_INTERNAL_H_ */