From e3960d1c57e57f33e0e846d615788f4ede73b945 Mon Sep 17 00:00:00 2001 From: Martin Liska Date: Tue, 7 Jul 2020 13:58:24 +0200 Subject: [PATCH] Add mallinfo2 function that support sizes >= 4GB. The current int type can easily overflow for allocation of more than 4GB. --- malloc/malloc.c | 35 ++++++++++++++++++++++++++++++----- malloc/malloc.h | 21 +++++++++++++++++++++ manual/memory.texi | 36 ++++++++++++++++++------------------ 3 files changed, 69 insertions(+), 23 deletions(-) diff --git a/malloc/malloc.c b/malloc/malloc.c index ee87ddbbf9..560fee2c31 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -638,6 +638,8 @@ libc_hidden_proto (__libc_mallopt) be kept as longs, the reported values may wrap around zero and thus be inaccurate. */ +struct mallinfo2 __libc_mallinfo2(void); + struct mallinfo __libc_mallinfo(void); @@ -4911,7 +4913,7 @@ __malloc_usable_size (void *m) */ static void -int_mallinfo (mstate av, struct mallinfo *m) +int_mallinfo (mstate av, struct mallinfo2 *m) { size_t i; mbinptr b; @@ -4974,10 +4976,10 @@ int_mallinfo (mstate av, struct mallinfo *m) } -struct mallinfo -__libc_mallinfo (void) +struct mallinfo2 +__libc_mallinfo2 (void) { - struct mallinfo m; + struct mallinfo2 m; mstate ar_ptr; if (__malloc_initialized < 0) @@ -4998,6 +5000,27 @@ __libc_mallinfo (void) return m; } +struct mallinfo +__libc_mallinfo (void) +{ + struct mallinfo m; + struct mallinfo2 m2 = __libc_mallinfo2 (); + + m.arena = m2.arena; + m.ordblks = m2.ordblks; + m.smblks = m2.smblks; + m.hblks = m2.hblks; + m.hblkhd = m2.hblkhd; + m.usmblks = m2.usmblks; + m.fsmblks = m2.fsmblks; + m.uordblks = m2.uordblks; + m.fordblks = m2.fordblks; + m.keepcost = m2.keepcost; + + return m; +} + + /* ------------------------------ malloc_stats ------------------------------ */ @@ -5016,7 +5039,7 @@ __malloc_stats (void) stderr->_flags2 |= _IO_FLAGS2_NOTCANCEL; for (i = 0, ar_ptr = &main_arena;; i++) { - struct mallinfo mi; + struct mallinfo2 mi; memset (&mi, 0, sizeof (mi)); __libc_lock_lock (ar_ptr->mutex); @@ -5632,6 +5655,8 @@ strong_alias (__libc_valloc, __valloc) weak_alias (__libc_valloc, valloc) strong_alias (__libc_pvalloc, __pvalloc) weak_alias (__libc_pvalloc, pvalloc) strong_alias (__libc_mallinfo, __mallinfo) weak_alias (__libc_mallinfo, mallinfo) +strong_alias (__libc_mallinfo2, __mallinfo2) +weak_alias (__libc_mallinfo2, mallinfo2) strong_alias (__libc_mallopt, __mallopt) weak_alias (__libc_mallopt, mallopt) weak_alias (__malloc_stats, malloc_stats) diff --git a/malloc/malloc.h b/malloc/malloc.h index e0e91a9331..e25b33462a 100644 --- a/malloc/malloc.h +++ b/malloc/malloc.h @@ -97,9 +97,30 @@ struct mallinfo int keepcost; /* top-most, releasable (via malloc_trim) space */ }; +/* SVID2/XPG mallinfo2 structure which can handle allocations + bigger than 4GB. */ + +struct mallinfo2 +{ + size_t arena; /* non-mmapped space allocated from system */ + size_t ordblks; /* number of free chunks */ + size_t smblks; /* number of fastbin blocks */ + size_t hblks; /* number of mmapped regions */ + size_t hblkhd; /* space in mmapped regions */ + size_t usmblks; /* always 0, preserved for backwards compatibility */ + size_t fsmblks; /* space available in freed fastbin blocks */ + size_t uordblks; /* total allocated space */ + size_t fordblks; /* total free space */ + size_t keepcost; /* top-most, releasable (via malloc_trim) space */ +}; + /* Returns a copy of the updated current mallinfo. */ +__MALLOC_DEPRECATED; extern struct mallinfo mallinfo (void) __THROW; +/* Returns a copy of the updated current mallinfo. */ +extern struct mallinfo2 mallinfo2 (void) __THROW; + /* SVID2/XPG mallopt options */ #ifndef M_MXFAST # define M_MXFAST 1 /* maximum request size for "fastbins" */ diff --git a/manual/memory.texi b/manual/memory.texi index aa5011e4f9..e5ea71bc6d 100644 --- a/manual/memory.texi +++ b/manual/memory.texi @@ -1505,50 +1505,50 @@ installing such hooks. @cindex allocation statistics You can get information about dynamic memory allocation by calling the -@code{mallinfo} function. This function and its associated data type +@code{mallinfo2} function. This function and its associated data type are declared in @file{malloc.h}; they are an extension of the standard SVID/XPG version. @pindex malloc.h -@deftp {Data Type} {struct mallinfo} +@deftp {Data Type} {struct mallinfo2} @standards{GNU, malloc.h} This structure type is used to return information about the dynamic memory allocator. It contains the following members: @table @code -@item int arena +@item size_t arena This is the total size of memory allocated with @code{sbrk} by @code{malloc}, in bytes. -@item int ordblks +@item size_t ordblks This is the number of chunks not in use. (The memory allocator -internally gets chunks of memory from the operating system, and then +size_ternally gets chunks of memory from the operating system, and then carves them up to satisfy individual @code{malloc} requests; @pxref{The GNU Allocator}.) -@item int smblks +@item size_t smblks This field is unused. -@item int hblks +@item size_t hblks This is the total number of chunks allocated with @code{mmap}. -@item int hblkhd +@item size_t hblkhd This is the total size of memory allocated with @code{mmap}, in bytes. -@item int usmblks +@item size_t usmblks This field is unused and always 0. -@item int fsmblks +@item size_t fsmblks This field is unused. -@item int uordblks +@item size_t uordblks This is the total size of memory occupied by chunks handed out by @code{malloc}. -@item int fordblks +@item size_t fordblks This is the total size of memory occupied by free (not in use) chunks. -@item int keepcost +@item size_t keepcost This is the size of the top-most releasable chunk that normally borders the end of the heap (i.e., the high end of the virtual address space's data segment). @@ -1556,7 +1556,7 @@ space's data segment). @end table @end deftp -@deftypefun {struct mallinfo} mallinfo (void) +@deftypefun {struct mallinfo2} mallinfo2 (void) @standards{SVID, malloc.h} @safety{@prelim{}@mtunsafe{@mtuinit{} @mtasuconst{:mallopt}}@asunsafe{@asuinit{} @asulock{}}@acunsafe{@acuinit{} @aculock{}}} @c Accessing mp_.n_mmaps and mp_.max_mmapped_mem, modified with atomics @@ -1564,7 +1564,7 @@ space's data segment). @c mark the statistics as unsafe, rather than the fast-path functions @c that collect the possibly inconsistent data. -@c __libc_mallinfo @mtuinit @mtasuconst:mallopt @asuinit @asulock @aculock +@c __libc_mallinfo2 @mtuinit @mtasuconst:mallopt @asuinit @asulock @aculock @c ptmalloc_init (once) dup @mtsenv @asulock @aculock @acsfd @acsmem @c mutex_lock dup @asulock @aculock @c int_mallinfo @mtasuconst:mallopt [mp_ access on main_arena] @@ -1577,7 +1577,7 @@ space's data segment). @c mutex_unlock @aculock This function returns information about the current dynamic memory usage -in a structure of type @code{struct mallinfo}. +in a structure of type @code{struct mallinfo2}. @end deftypefun @node Summary of Malloc @@ -1644,7 +1644,7 @@ A pointer to a function that @code{free} uses whenever it is called. A pointer to a function that @code{aligned_alloc}, @code{memalign}, @code{posix_memalign} and @code{valloc} use whenever they are called. -@item struct mallinfo mallinfo (void) +@item struct mallinfo2 mallinfo2 (void) Return information about the current dynamic memory usage. @xref{Statistics of Malloc}. @end table @@ -1970,7 +1970,7 @@ In addition, very old applications may use the obsolete @code{cfree} function. Further @code{malloc}-related functions such as @code{mallopt} or -@code{mallinfo} will not have any effect or return incorrect statistics +@code{mallinfo2} will not have any effect or return incorrect statistics when a replacement @code{malloc} is in use. However, failure to replace these functions typically does not result in crashes or other incorrect application behavior, but may result in static linking failures. -- 2.43.5