Gitweb:
https://git.exim.org/exim.git/commitdiff/60e2e80a81b642a78a58997719dc26828eed2c2b
Commit: 60e2e80a81b642a78a58997719dc26828eed2c2b
Parent: 4381d60bc96bed88d96e8cc6b534dd0dcd48163f
Author: Jeremy Harris <jgh146exb@???>
AuthorDate: Tue Jan 28 22:40:57 2020 +0000
Committer: Jeremy Harris <jgh146exb@???>
CommitDate: Tue Jan 28 22:40:57 2020 +0000
Taint: mmap no longer needed
---
src/src/store.c | 116 ++++++++++++++------------------------------------------
1 file changed, 29 insertions(+), 87 deletions(-)
diff --git a/src/src/store.c b/src/src/store.c
index 8e77656..346b0cc 100644
--- a/src/src/store.c
+++ b/src/src/store.c
@@ -49,13 +49,6 @@ The following different types of store are recognized:
to not copy untrusted data into untainted memory, as downstream taint-checks
would be avoided.
- Internally we currently use malloc for nontainted pools, and mmap for tainted
- pools. The disparity is for speed of testing the taintedness of pointers;
- because Linux appears to use distinct non-overlapping address allocations for
- mmap vs. everything else, which means only two pointer-compares suffice for the
- test. Other OS' cannot use that optimisation, and a more lengthy test against
- the limits of tainted-pool allcations has to be done.
-
Intermediate layers (eg. the string functions) can test for taint, and use this
for ensurinng that results have proper state. For example the
string_vformat_trc() routing supporting the string_sprintf() interface will
@@ -172,10 +165,8 @@ static const uschar * poolclass[NPOOLS] = {
#endif
-static void * store_mmap(int, const char *, int);
static void * internal_store_malloc(int, const char *, int);
-static void internal_untainted_free(void *, const char *, int linenumber);
-static void internal_tainted_free(storeblock *, const char *, int linenumber);
+static void internal_store_free(void *, const char *, int linenumber);
/******************************************************************************/
@@ -269,10 +260,7 @@ if (size > yield_length[pool])
{
/* Give up on this block, because it's too small */
nblocks[pool]--;
- if (pool < POOL_TAINT_BASE)
- internal_untainted_free(newblock, func, linenumber);
- else
- internal_tainted_free(newblock, func, linenumber);
+ internal_store_free(newblock, func, linenumber);
newblock = NULL;
}
@@ -288,9 +276,7 @@ if (size > yield_length[pool])
if (++nblocks[pool] > maxblocks[pool])
maxblocks[pool] = nblocks[pool];
- newblock = tainted
- ? store_mmap(mlength, func, linenumber)
- : internal_store_malloc(mlength, func, linenumber);
+ newblock = internal_store_malloc(mlength, func, linenumber);
newblock->next = NULL;
newblock->length = length;
@@ -530,10 +516,7 @@ while ((b = bb))
nbytes[pool] -= siz;
pool_malloc -= siz;
nblocks[pool]--;
- if (pool < POOL_TAINT_BASE)
- internal_untainted_free(b, func, linenumber);
- else
- internal_tainted_free(b, func, linenumber);
+ internal_store_free(b, func, linenumber);
}
/* Cut out the debugging stuff for utilities, but stop picky compilers from
@@ -765,52 +748,6 @@ return (void *)newtext;
-/******************************************************************************/
-static void *
-store_alloc_tail(void * yield, int size, const char * func, int line,
- const uschar * type)
-{
-if ((nonpool_malloc += size) > max_nonpool_malloc)
- max_nonpool_malloc = nonpool_malloc;
-
-/* Cut out the debugging stuff for utilities, but stop picky compilers from
-giving warnings. */
-
-#ifdef COMPILE_UTILITY
-func = func; line = line; type = type;
-#else
-
-/* If running in test harness, spend time making sure all the new store
-is not filled with zeros so as to catch problems. */
-
-if (f.running_in_test_harness)
- memset(yield, 0xF0, (size_t)size);
-DEBUG(D_memory) debug_printf("--%6s %6p %5d bytes\t%-14s %4d\tpool %5d nonpool %5d\n",
- type, yield, size, func, line, pool_malloc, nonpool_malloc);
-#endif /* COMPILE_UTILITY */
-
-return yield;
-}
-
-/*************************************************
-* Mmap store *
-*************************************************/
-
-static void *
-store_mmap(int size, const char * func, int line)
-{
-void * yield, * top;
-
-if (size < 16) size = 16;
-
-if (!(yield = mmap(NULL, (size_t)size,
- PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)))
- log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to mmap %d bytes of memory: "
- "called from line %d of %s", size, line, func);
-
-return store_alloc_tail(yield, size, func, line, US"Mmap");
-}
-
/*************************************************
* Malloc store *
*************************************************/
@@ -822,13 +759,13 @@ function is called via the macro store_malloc().
Arguments:
size amount of store wanted
func function from which called
- linenumber line number in source file
+ line line number in source file
Returns: pointer to gotten store (panic on failure)
*/
static void *
-internal_store_malloc(int size, const char *func, int linenumber)
+internal_store_malloc(int size, const char *func, int line)
{
void * yield;
@@ -836,9 +773,28 @@ if (size < 16) size = 16;
if (!(yield = malloc((size_t)size)))
log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to malloc %d bytes of memory: "
- "called from line %d in %s", size, linenumber, func);
+ "called from line %d in %s", size, line, func);
+
+if ((nonpool_malloc += size) > max_nonpool_malloc)
+ max_nonpool_malloc = nonpool_malloc;
+
+/* Cut out the debugging stuff for utilities, but stop picky compilers from
+giving warnings. */
+
+#ifdef COMPILE_UTILITY
+func = func; line = line;
+#else
+
+/* If running in test harness, spend time making sure all the new store
+is not filled with zeros so as to catch problems. */
-return store_alloc_tail(yield, size, func, linenumber, US"Malloc");
+if (f.running_in_test_harness)
+ memset(yield, 0xF0, (size_t)size);
+DEBUG(D_memory) debug_printf("--Malloc %6p %5d bytes\t%-14s %4d\tpool %5d nonpool %5d\n",
+ yield, size, func, line, pool_malloc, nonpool_malloc);
+#endif /* COMPILE_UTILITY */
+
+return yield;
}
void *
@@ -865,7 +821,7 @@ Returns: nothing
*/
static void
-internal_untainted_free(void * block, const char * func, int linenumber)
+internal_store_free(void * block, const char * func, int linenumber)
{
#ifdef COMPILE_UTILITY
func = func;
@@ -881,21 +837,7 @@ void
store_free_3(void * block, const char * func, int linenumber)
{
n_nonpool_blocks--;
-internal_untainted_free(block, func, linenumber);
-}
-
-/******************************************************************************/
-static void
-internal_tainted_free(storeblock * block, const char * func, int linenumber)
-{
-#ifdef COMPILE_UTILITY
-func = func;
-linenumber = linenumber;
-#else
-DEBUG(D_memory)
- debug_printf("---Unmap %6p %-20s %4d\n", block, func, linenumber);
-#endif
-munmap((void *)block, block->length + ALIGNED_SIZEOF_STOREBLOCK);
+internal_store_free(block, func, linenumber);
}
/******************************************************************************/
