Fix memory leak in shm_get_var() when variable is corrupted#21388
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ndossche wants to merge 2 commits intophp:PHP-8.4from
Open
Fix memory leak in shm_get_var() when variable is corrupted#21388ndossche wants to merge 2 commits intophp:PHP-8.4from
ndossche wants to merge 2 commits intophp:PHP-8.4from
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This path wasn't tested (clearly). To trigger this we use FFI, which seemed like the easiest way that doesn't involve using another process messing with the shared memory.
devnexen
reviewed
Mar 9, 2026
| PHP_VAR_UNSERIALIZE_INIT(var_hash); | ||
| if (php_var_unserialize(return_value, (const unsigned char **) &shm_data, (unsigned char *) shm_data + shm_var->length, &var_hash) != 1) { | ||
| int res = php_var_unserialize(return_value, (const unsigned char **) &shm_data, (unsigned char *) shm_data + shm_var->length, &var_hash); | ||
| PHP_VAR_UNSERIALIZE_DESTROY(var_hash); |
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is it possible to minimise the change (i.e. keeping RETVAL_FALSE) ?
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Someone else is going to change it to RETURN_FALSE on master anyway, so might as well already do it
devnexen
approved these changes
Mar 9, 2026
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This path wasn't tested (clearly).
To trigger this we use FFI, which seemed like the easiest way that doesn't involve using another process messing with the shared memory.
There are more mistakes against php_var_unserialize to be found, but it just takes a while to come up with a test that triggers the necessary code paths.