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| author | Rucha Deodhar <rucha.deodhar@mariadb.com> | 2022-07-25 14:34:44 +0530 |
|---|---|---|
| committer | Rucha Deodhar <rucha.deodhar@mariadb.com> | 2022-07-25 22:13:40 +0530 |
| commit | 46ff660883aade25f16abb13588f0a1934e9da56 (patch) | |
| tree | 2744b6b4fcb347d33a6b767a8fd457b30f3b17e5 /sql/item_jsonfunc.cc | |
| parent | f1c8749f46f2479b9298195a7799f44ce1529757 (diff) | |
| download | mariadb-git-46ff660883aade25f16abb13588f0a1934e9da56.tar.gz | |
This commit is a fixup for MDEV-28762
Diffstat (limited to 'sql/item_jsonfunc.cc')
| -rw-r--r-- | sql/item_jsonfunc.cc | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/sql/item_jsonfunc.cc b/sql/item_jsonfunc.cc index b502db0d867..2fa6b19d95f 100644 --- a/sql/item_jsonfunc.cc +++ b/sql/item_jsonfunc.cc @@ -21,6 +21,22 @@ #include "sql_parse.h" // For check_stack_overrun /* + Allocating memory and *also* using it (reading and + writing from it) because some build instructions cause + compiler to optimize out stack_used_up. Since alloca() + here depends on stack_used_up, it doesnt get executed + correctly and causes json_debug_nonembedded to fail + ( --error ER_STACK_OVERRUN_NEED_MORE does not occur). +*/ +#define ALLOCATE_MEM_ON_STACK(A) do \ + { \ + uchar *array= (uchar*)alloca(A); \ + array[0]= 1; \ + array[0]++; \ + array[0] ? array[0]++ : array[0]--; \ + } while(0) + +/* Compare ASCII string against the string with the specified character set. Only compares the equality, case insencitive. @@ -138,9 +154,10 @@ int json_path_parts_compare( long arbitrary_var; long stack_used_up= (available_stack_size(current_thd->thread_stack, &arbitrary_var)); DBUG_EXECUTE_IF("json_check_min_stack_requirement", - {alloca(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); + {ALLOCATE_MEM_ON_STACK(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); if (check_stack_overrun(current_thd, STACK_MIN_SIZE , NULL)) return 1; + while (a <= a_end) { if (b > b_end) @@ -1139,15 +1156,10 @@ static int check_contains(json_engine_t *js, json_engine_t *value) long arbitrary_var; long stack_used_up= (available_stack_size(current_thd->thread_stack, &arbitrary_var)); DBUG_EXECUTE_IF("json_check_min_stack_requirement", - {alloca(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); + {ALLOCATE_MEM_ON_STACK(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); if (check_stack_overrun(current_thd, STACK_MIN_SIZE , NULL)) return 1; - DBUG_EXECUTE_IF("json_check_min_stack_requirement", - {alloca(my_thread_stack_size-(STACK_MIN_SIZE));}); - if (check_stack_overrun(current_thd, STACK_MIN_SIZE, NULL)) - return 0; - switch (js->value_type) { case JSON_VALUE_OBJECT: @@ -2040,7 +2052,7 @@ static int do_merge(String *str, json_engine_t *je1, json_engine_t *je2) long arbitrary_var; long stack_used_up= (available_stack_size(current_thd->thread_stack, &arbitrary_var)); DBUG_EXECUTE_IF("json_check_min_stack_requirement", - {alloca(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); + {ALLOCATE_MEM_ON_STACK(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); if (check_stack_overrun(current_thd, STACK_MIN_SIZE , NULL)) return 1; @@ -2379,7 +2391,7 @@ static int do_merge_patch(String *str, json_engine_t *je1, json_engine_t *je2, long arbitrary_var; long stack_used_up= (available_stack_size(current_thd->thread_stack, &arbitrary_var)); DBUG_EXECUTE_IF("json_check_min_stack_requirement", - {alloca(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); + {ALLOCATE_MEM_ON_STACK(my_thread_stack_size-stack_used_up-STACK_MIN_SIZE);}); if (check_stack_overrun(current_thd, STACK_MIN_SIZE , NULL)) return 1; |