The patch titled Subject: kasan: call print_report from kasan_report_invalid_free has been added to the -mm tree. Its filename is kasan-call-print_report-from-kasan_report_invalid_free.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/kasan-call-print_report-from-kasan_report_invalid_free.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/kasan-call-print_report-from-kasan_report_invalid_free.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: kasan: call print_report from kasan_report_invalid_free Call print_report() in kasan_report_invalid_free() instead of calling printing functions directly. Compared to the existing implementation of kasan_report_invalid_free(), print_report() makes sure that the buggy address has metadata before printing it. The change requires adding a report type field into kasan_access_info and using it accordingly. kasan_report_async() is left as is, as using print_report() will only complicate the code. Link: https://lkml.kernel.org/r/9ea6f0604c5d2e1fb28d93dc6c44232c1f8017fe.1646237226.git.andreyknvl@xxxxxxxxxx Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Marco Elver <elver@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/kasan/kasan.h | 6 ++++++ mm/kasan/report.c | 42 ++++++++++++++++++++++++++---------------- 2 files changed, 32 insertions(+), 16 deletions(-) --- a/mm/kasan/kasan.h~kasan-call-print_report-from-kasan_report_invalid_free +++ a/mm/kasan/kasan.h @@ -127,7 +127,13 @@ static inline bool kasan_sync_fault_poss #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE) #define META_ROWS_AROUND_ADDR 2 +enum kasan_report_type { + KASAN_REPORT_ACCESS, + KASAN_REPORT_INVALID_FREE, +}; + struct kasan_access_info { + enum kasan_report_type type; void *access_addr; void *first_bad_addr; size_t access_size; --- a/mm/kasan/report.c~kasan-call-print_report-from-kasan_report_invalid_free +++ a/mm/kasan/report.c @@ -86,6 +86,12 @@ __setup("kasan_multi_shot", kasan_set_mu static void print_error_description(struct kasan_access_info *info) { + if (info->type == KASAN_REPORT_INVALID_FREE) { + pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", + (void *)info->ip); + return; + } + pr_err("BUG: KASAN: %s in %pS\n", kasan_get_bug_type(info), (void *)info->ip); if (info->access_size) @@ -386,22 +392,6 @@ static bool report_enabled(void) return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags); } -void kasan_report_invalid_free(void *object, unsigned long ip) -{ - unsigned long flags; - u8 tag = get_tag(object); - - object = kasan_reset_tag(object); - - start_report(&flags, true); - pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", (void *)ip); - kasan_print_tags(tag, object); - pr_err("\n"); - print_address_description(object, tag); - print_memory_metadata(object); - end_report(&flags, object); -} - #ifdef CONFIG_KASAN_HW_TAGS void kasan_report_async(void) { @@ -435,6 +425,25 @@ static void print_report(struct kasan_ac } } +void kasan_report_invalid_free(void *ptr, unsigned long ip) +{ + unsigned long flags; + struct kasan_access_info info; + + start_report(&flags, true); + + info.type = KASAN_REPORT_INVALID_FREE; + info.access_addr = ptr; + info.first_bad_addr = kasan_reset_tag(ptr); + info.access_size = 0; + info.is_write = false; + info.ip = ip; + + print_report(&info); + + end_report(&flags, ptr); +} + bool kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip) { @@ -451,6 +460,7 @@ bool kasan_report(unsigned long addr, si start_report(&irq_flags, true); + info.type = KASAN_REPORT_ACCESS; info.access_addr = ptr; info.first_bad_addr = kasan_find_first_bad_addr(ptr, size); info.access_size = size; _ Patches currently in -mm which might be from andreyknvl@xxxxxxxxxx are kasan-page_alloc-deduplicate-should_skip_kasan_poison.patch kasan-page_alloc-move-tag_clear_highpage-out-of-kernel_init_free_pages.patch kasan-page_alloc-merge-kasan_free_pages-into-free_pages_prepare.patch kasan-page_alloc-simplify-kasan_poison_pages-call-site.patch kasan-page_alloc-init-memory-of-skipped-pages-on-free.patch kasan-drop-skip_kasan_poison-variable-in-free_pages_prepare.patch mm-clarify-__gfp_zerotags-comment.patch kasan-only-apply-__gfp_zerotags-when-memory-is-zeroed.patch kasan-page_alloc-refactor-init-checks-in-post_alloc_hook.patch kasan-page_alloc-merge-kasan_alloc_pages-into-post_alloc_hook.patch kasan-page_alloc-combine-tag_clear_highpage-calls-in-post_alloc_hook.patch kasan-page_alloc-move-setpageskipkasanpoison-in-post_alloc_hook.patch kasan-page_alloc-move-kernel_init_free_pages-in-post_alloc_hook.patch kasan-page_alloc-rework-kasan_unpoison_pages-call-site.patch kasan-clean-up-metadata-byte-definitions.patch kasan-define-kasan_vmalloc_invalid-for-sw_tags.patch kasan-x86-arm64-s390-rename-functions-for-modules-shadow.patch kasan-vmalloc-drop-outdated-vm_kasan-comment.patch kasan-reorder-vmalloc-hooks.patch kasan-add-wrappers-for-vmalloc-hooks.patch kasan-vmalloc-reset-tags-in-vmalloc-functions.patch kasan-fork-reset-pointer-tags-of-vmapped-stacks.patch kasan-arm64-reset-pointer-tags-of-vmapped-stacks.patch kasan-fork-reset-pointer-tags-of-vmapped-stacks-fix.patch kasan-vmalloc-add-vmalloc-tagging-for-sw_tags.patch kasan-vmalloc-arm64-mark-vmalloc-mappings-as-pgprot_tagged.patch kasan-vmalloc-unpoison-vm_alloc-pages-after-mapping.patch kasan-mm-only-define-___gfp_skip_kasan_poison-with-hw_tags.patch kasan-page_alloc-allow-skipping-unpoisoning-for-hw_tags.patch kasan-page_alloc-allow-skipping-memory-init-for-hw_tags.patch kasan-vmalloc-add-vmalloc-tagging-for-hw_tags.patch kasan-vmalloc-only-tag-normal-vmalloc-allocations.patch kasan-arm64-dont-tag-executable-vmalloc-allocations.patch kasan-mark-kasan_arg_stacktrace-as-__initdata.patch kasan-clean-up-feature-flags-for-hw_tags-mode.patch kasan-add-kasanvmalloc-command-line-flag.patch kasan-allow-enabling-kasan_vmalloc-and-sw-hw_tags.patch arm64-select-kasan_vmalloc-for-sw-hw_tags-modes.patch kasan-documentation-updates.patch kasan-improve-vmalloc-tests.patch kasan-improve-vmalloc-tests-fix-2.patch kasan-improve-vmalloc-tests-fix-3.patch kasan-test-support-async-again-and-asymm-modes-for-hw_tags.patch kasan-print-virtual-mapping-info-in-reports.patch kasan-drop-addr-check-from-describe_object_addr.patch kasan-more-line-breaks-in-reports.patch kasan-rearrange-stack-frame-info-in-reports.patch kasan-improve-stack-frame-info-in-reports.patch kasan-print-basic-stack-frame-info-for-sw_tags.patch kasan-simplify-async-check-in-end_report.patch kasan-simplify-kasan_update_kunit_status-and-call-sites.patch kasan-check-config_kasan_kunit_test-instead-of-config_kunit.patch kasan-move-update_kunit_status-to-start_report.patch kasan-move-disable_trace_on_warning-to-start_report.patch kasan-split-out-print_report-from-__kasan_report.patch kasan-simplify-kasan_find_first_bad_addr-call-sites.patch kasan-restructure-kasan_report.patch kasan-merge-__kasan_report-into-kasan_report.patch kasan-call-print_report-from-kasan_report_invalid_free.patch kasan-move-and-simplify-kasan_report_async.patch kasan-rename-kasan_access_info-to-kasan_report_info.patch kasan-add-comment-about-uaccess-regions-to-kasan_report.patch kasan-respect-kasan_bit_reported-in-all-reporting-routines.patch kasan-reorder-reporting-functions.patch kasan-move-and-hide-kasan_save_enable-restore_multi_shot.patch kasan-disable-lockdep-when-printing-reports.patch