diff --git a/src/san_bump.c b/src/san_bump.c index 09ed18ca..11031290 100644 --- a/src/san_bump.c +++ b/src/san_bump.c @@ -31,6 +31,7 @@ san_bump_alloc(tsdn_t *tsdn, san_bump_alloc_t *sba, pac_t *pac, bool err = san_bump_grow_locked( tsdn, sba, pac, ehooks, guarded_size); if (err) { + sba->curr_reg = to_destroy; goto label_err; } } else { diff --git a/test/unit/san_bump.c b/test/unit/san_bump.c index 9aa0210e..54d8583d 100644 --- a/test/unit/san_bump.c +++ b/test/unit/san_bump.c @@ -4,6 +4,50 @@ #include "jemalloc/internal/arena_structs.h" #include "jemalloc/internal/san_bump.h" +static extent_hooks_t *san_bump_default_hooks; +static extent_hooks_t san_bump_hooks; +static bool fail_retained_alloc; +static unsigned retained_alloc_fail_calls; + +static void * +san_bump_fail_alloc_hook(extent_hooks_t *UNUSED extent_hooks, void *new_addr, + size_t size, size_t alignment, bool *zero, bool *commit, + unsigned arena_ind) { + if (fail_retained_alloc && new_addr == NULL + && size >= SBA_RETAINED_ALLOC_SIZE) { + retained_alloc_fail_calls++; + return NULL; + } + return san_bump_default_hooks->alloc(san_bump_default_hooks, new_addr, + size, alignment, zero, commit, arena_ind); +} + +static void +install_san_bump_fail_alloc_hooks(unsigned arena_ind) { + size_t hooks_mib[3]; + size_t hooks_miblen = sizeof(hooks_mib) / sizeof(size_t); + size_t old_size = sizeof(extent_hooks_t *); + size_t new_size = sizeof(extent_hooks_t *); + extent_hooks_t *new_hooks; + extent_hooks_t *old_hooks; + + expect_d_eq( + mallctlnametomib("arena.0.extent_hooks", hooks_mib, &hooks_miblen), + 0, "Unexpected mallctlnametomib() failure"); + hooks_mib[1] = (size_t)arena_ind; + expect_d_eq(mallctlbymib(hooks_mib, hooks_miblen, (void *)&old_hooks, + &old_size, NULL, 0), + 0, "Unexpected extent_hooks error"); + + san_bump_default_hooks = old_hooks; + san_bump_hooks = *old_hooks; + san_bump_hooks.alloc = san_bump_fail_alloc_hook; + new_hooks = &san_bump_hooks; + expect_d_eq(mallctlbymib(hooks_mib, hooks_miblen, NULL, NULL, + (void *)&new_hooks, new_size), + 0, "Unexpected extent_hooks install failure"); +} + TEST_BEGIN(test_san_bump_alloc) { test_skip_if(!maps_coalesce || !opt_retain); @@ -69,6 +113,48 @@ TEST_BEGIN(test_san_bump_alloc) { } TEST_END +TEST_BEGIN(test_failed_grow_preserves_curr_reg) { + test_skip_if(!maps_coalesce || !opt_retain); + + tsdn_t *tsdn = tsdn_fetch(); + + san_bump_alloc_t sba; + san_bump_alloc_init(&sba); + + unsigned arena_ind = do_arena_create(0, 0); + assert_u_ne(arena_ind, UINT_MAX, "Failed to create an arena"); + install_san_bump_fail_alloc_hooks(arena_ind); + + arena_t *arena = arena_get(tsdn, arena_ind, false); + pac_t *pac = &arena->pa_shard.pac; + + size_t small_alloc_size = PAGE * 16; + edata_t *edata = san_bump_alloc(tsdn, &sba, pac, pac_ehooks_get(pac), + small_alloc_size, /* zero */ false); + expect_ptr_not_null(edata, "Initial san_bump allocation failed"); + expect_ptr_not_null(sba.curr_reg, + "Expected retained region remainder after initial allocation"); + + fail_retained_alloc = true; + retained_alloc_fail_calls = 0; + + edata_t *failed = san_bump_alloc(tsdn, &sba, pac, pac_ehooks_get(pac), + SBA_RETAINED_ALLOC_SIZE, /* zero */ false); + expect_ptr_null(failed, "Expected retained grow allocation failure"); + expect_u_eq(retained_alloc_fail_calls, 1, + "Expected exactly one failed retained allocation attempt"); + + edata_t *reused = san_bump_alloc(tsdn, &sba, pac, pac_ehooks_get(pac), + small_alloc_size, /* zero */ false); + expect_ptr_not_null( + reused, "Expected allocator to reuse preexisting current region"); + expect_u_eq(retained_alloc_fail_calls, 1, + "Reuse path should not attempt another retained grow allocation"); + + fail_retained_alloc = false; +} +TEST_END + TEST_BEGIN(test_large_alloc_size) { test_skip_if(!maps_coalesce || !opt_retain); @@ -105,5 +191,6 @@ TEST_END int main(void) { - return test(test_san_bump_alloc, test_large_alloc_size); + return test(test_san_bump_alloc, test_failed_grow_preserves_curr_reg, + test_large_alloc_size); }