From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by gabe.freedesktop.org (Postfix) with ESMTPS id CE6A110E6EF for ; Thu, 26 Oct 2023 02:20:56 +0000 (UTC) From: Vignesh Raman To: igt-dev@lists.freedesktop.org Date: Thu, 26 Oct 2023 07:50:41 +0530 Message-Id: <20231026022041.1851831-1-vignesh.raman@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [igt-dev] [PATCH i-g-t] lib/igt_kms: Fix memory corruption List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: helen.koike@collabora.com, daniels@collabora.com Errors-To: igt-dev-bounces@lists.freedesktop.org Sender: "igt-dev" List-ID: In crosvm, the kernel reports 16 for count_crtcs, which exceeds IGT_MAX_PIPES set to 8. The function igt_display_require allocates memory for IGT_MAX_PIPES members of igt_pipe_t structures, but then writes into it based on the count_crtcs reported by the kernel, resulting in memory corruption. # malloc(): corrupted top size # Received signal SIGABRT. # Stack trace: # #0 [fatal_sig_handler+0x17b] # #1 [__sigaction+0x40] # #2 [pthread_key_delete+0x14c] # #3 [gsignal+0x12] # #4 [abort+0xd3] # #5 [__fsetlocking+0x290] # #6 [timer_settime+0x37a] # #7 [__default_morecore+0x1f1b] # #8 [__libc_calloc+0x161] # #9 [drmModeGetPlaneResources+0x44] # #10 [igt_display_require+0x194] # #11 [__igt_unique____real_main1356+0x93c] # #12 [main+0x3f] # #13 [__libc_init_first+0x8a] # #14 [__libc_start_main+0x85] # #15 [_start+0x21] Limit the loop which initializes igt_pipe_t structure to a maximum of IGT_MAX_PIPES iterations, ensuring it does not exceed the allocated pipe count. This prevents igt_display_require overwriting the heap and avoids memory corruption. This fix is required for drm-ci to run igt tests on virtio-gpu. Signed-off-by: Vignesh Raman --- lib/igt_kms.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/igt_kms.c b/lib/igt_kms.c index 453103f90..f3484a942 100644 --- a/lib/igt_kms.c +++ b/lib/igt_kms.c @@ -2774,7 +2774,7 @@ void igt_display_require(igt_display_t *display, int drm_fd) display->pipes = calloc(sizeof(igt_pipe_t), display->n_pipes); igt_assert_f(display->pipes, "Failed to allocate memory for %d pipes\n", display->n_pipes); - for (i = 0; i < resources->count_crtcs; i++) { + for (i = 0; i < min(resources->count_crtcs, IGT_MAX_PIPES); i++) { igt_pipe_t *pipe; int pipe_enum = (is_intel_dev)? __intel_get_pipe_from_crtc_id(drm_fd, -- 2.40.1