| Message ID | 20211029085521.2203458-1-siddhesh@sourceware.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] Handle NULL input to malloc_usable_size [BZ #28506] | expand |
On Fri, Oct 29, 2021 at 02:25:21PM +0530, Siddhesh Poyarekar wrote: > Hoist the NULL check for malloc_usable_size into its entry points in > malloc-debug and malloc and assume non-NULL in all callees. This fixes > BZ #28506 > > Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> > --- > malloc/malloc-debug.c | 12 ++++++------ > malloc/malloc.c | 24 ++++++++---------------- > malloc/tst-malloc-usable.c | 21 ++++++++------------- > 3 files changed, 22 insertions(+), 35 deletions(-) > > diff --git a/malloc/malloc-debug.c b/malloc/malloc-debug.c > index 9922ef5f25..5e954d7dc2 100644 > --- a/malloc/malloc-debug.c > +++ b/malloc/malloc-debug.c > @@ -399,17 +399,17 @@ strong_alias (__debug_calloc, calloc) > size_t > malloc_usable_size (void *mem) > { > + if (mem == NULL) > + return 0; > + > if (__is_malloc_debug_enabled (MALLOC_MCHECK_HOOK)) > return mcheck_usable_size (mem); > if (__is_malloc_debug_enabled (MALLOC_CHECK_HOOK)) > return malloc_check_get_size (mem); > > - if (mem != NULL) > - { > - mchunkptr p = mem2chunk (mem); > - if (DUMPED_MAIN_ARENA_CHUNK (p)) > - return chunksize (p) - SIZE_SZ; > - } > + mchunkptr p = mem2chunk (mem); > + if (DUMPED_MAIN_ARENA_CHUNK (p)) > + return chunksize (p) - SIZE_SZ; > > return musable (mem); > } > diff --git a/malloc/malloc.c b/malloc/malloc.c > index 2ba1fee144..a9dfc82788 100644 > --- a/malloc/malloc.c > +++ b/malloc/malloc.c > @@ -5007,20 +5007,13 @@ __malloc_trim (size_t s) > static size_t > musable (void *mem) > { > - mchunkptr p; > - if (mem != 0) > - { > - size_t result = 0; > - > - p = mem2chunk (mem); > + mchunkptr p = mem2chunk (mem); > > - if (chunk_is_mmapped (p)) > - result = chunksize (p) - CHUNK_HDR_SZ; > - else if (inuse (p)) > - result = memsize (p); > + if (chunk_is_mmapped (p)) > + return chunksize (p) - CHUNK_HDR_SZ; > + else if (inuse (p)) > + return memsize (p); > > - return result; > - } > return 0; > } > > @@ -5028,10 +5021,9 @@ musable (void *mem) > size_t > __malloc_usable_size (void *m) > { > - size_t result; > - > - result = musable (m); > - return result; > + if (m == NULL) > + return 0; > + return musable (m); > } > #endif > > diff --git a/malloc/tst-malloc-usable.c b/malloc/tst-malloc-usable.c > index a1074b782a..e50cadcf10 100644 > --- a/malloc/tst-malloc-usable.c > +++ b/malloc/tst-malloc-usable.c > @@ -21,29 +21,24 @@ > #include <malloc.h> > #include <string.h> > #include <stdio.h> > +#include <support/support.h> > +#include <support/check.h> > > static int > do_test (void) > { > size_t usable_size; > void *p = malloc (7); > - if (!p) > - { > - printf ("memory allocation failed\n"); > - return 1; > - } > > + TEST_VERIFY_EXIT (p != NULL); > usable_size = malloc_usable_size (p); > - if (usable_size != 7) > - { > - printf ("malloc_usable_size: expected 7 but got %zu\n", usable_size); > - return 1; > - } > - > + TEST_COMPARE (usable_size, 7); > memset (p, 0, usable_size); > free (p); > + > + TEST_COMPARE (malloc_usable_size (NULL), 0); > + > return 0; > } > > -#define TEST_FUNCTION do_test () > -#include "../test-skeleton.c" > +#include "support/test-driver.c" Also looks sensible, so: Reviewed-by: Richard W.M. Jones <rjones@redhat.com> Rich.
* Siddhesh Poyarekar: > Hoist the NULL check for malloc_usable_size into its entry points in > malloc-debug and malloc and assume non-NULL in all callees. This fixes > BZ #28506 > > Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> I forgot: If you use Signed-off-by: for real (without FSF copyright assignment), you need to adjust the copyright headers. The rest of the patch looks okay to me. Thanks, Florian
diff --git a/malloc/malloc-debug.c b/malloc/malloc-debug.c index 9922ef5f25..5e954d7dc2 100644 --- a/malloc/malloc-debug.c +++ b/malloc/malloc-debug.c @@ -399,17 +399,17 @@ strong_alias (__debug_calloc, calloc) size_t malloc_usable_size (void *mem) { + if (mem == NULL) + return 0; + if (__is_malloc_debug_enabled (MALLOC_MCHECK_HOOK)) return mcheck_usable_size (mem); if (__is_malloc_debug_enabled (MALLOC_CHECK_HOOK)) return malloc_check_get_size (mem); - if (mem != NULL) - { - mchunkptr p = mem2chunk (mem); - if (DUMPED_MAIN_ARENA_CHUNK (p)) - return chunksize (p) - SIZE_SZ; - } + mchunkptr p = mem2chunk (mem); + if (DUMPED_MAIN_ARENA_CHUNK (p)) + return chunksize (p) - SIZE_SZ; return musable (mem); } diff --git a/malloc/malloc.c b/malloc/malloc.c index 2ba1fee144..a9dfc82788 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -5007,20 +5007,13 @@ __malloc_trim (size_t s) static size_t musable (void *mem) { - mchunkptr p; - if (mem != 0) - { - size_t result = 0; - - p = mem2chunk (mem); + mchunkptr p = mem2chunk (mem); - if (chunk_is_mmapped (p)) - result = chunksize (p) - CHUNK_HDR_SZ; - else if (inuse (p)) - result = memsize (p); + if (chunk_is_mmapped (p)) + return chunksize (p) - CHUNK_HDR_SZ; + else if (inuse (p)) + return memsize (p); - return result; - } return 0; } @@ -5028,10 +5021,9 @@ musable (void *mem) size_t __malloc_usable_size (void *m) { - size_t result; - - result = musable (m); - return result; + if (m == NULL) + return 0; + return musable (m); } #endif diff --git a/malloc/tst-malloc-usable.c b/malloc/tst-malloc-usable.c index a1074b782a..e50cadcf10 100644 --- a/malloc/tst-malloc-usable.c +++ b/malloc/tst-malloc-usable.c @@ -21,29 +21,24 @@ #include <malloc.h> #include <string.h> #include <stdio.h> +#include <support/support.h> +#include <support/check.h> static int do_test (void) { size_t usable_size; void *p = malloc (7); - if (!p) - { - printf ("memory allocation failed\n"); - return 1; - } + TEST_VERIFY_EXIT (p != NULL); usable_size = malloc_usable_size (p); - if (usable_size != 7) - { - printf ("malloc_usable_size: expected 7 but got %zu\n", usable_size); - return 1; - } - + TEST_COMPARE (usable_size, 7); memset (p, 0, usable_size); free (p); + + TEST_COMPARE (malloc_usable_size (NULL), 0); + return 0; } -#define TEST_FUNCTION do_test () -#include "../test-skeleton.c" +#include "support/test-driver.c"
Hoist the NULL check for malloc_usable_size into its entry points in malloc-debug and malloc and assume non-NULL in all callees. This fixes BZ #28506 Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> --- malloc/malloc-debug.c | 12 ++++++------ malloc/malloc.c | 24 ++++++++---------------- malloc/tst-malloc-usable.c | 21 ++++++++------------- 3 files changed, 22 insertions(+), 35 deletions(-)