From ae0119f5f73b1e9cf7177fbbeea68d74c5751def Mon Sep 17 00:00:00 2001 From: Xie XiuQi Date: Tue, 6 Sep 2016 16:55:38 +0800 Subject: [PATCH] drm: fix signed integer overflow Use 1UL for unsigned long, or we'll meet a overflow issue with UBSAN. [ 15.589489] UBSAN: Undefined behaviour in drivers/gpu/drm/drm_hashtab.c:145:35 [ 15.589500] signed integer overflow: [ 15.589999] -2147483648 - 1 cannot be represented in type 'int' [ 15.590434] CPU: 2 PID: 294 Comm: plymouthd Not tainted 3.10.0-327.28.3.el7.x86_64 #1 [ 15.590653] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 01/07/2011 [ 15.591001] 1ffff1000670fe83 000000000d6b385e ffff88003387f3e0 ffffffff81ee3140 [ 15.591028] ffff88003387f3f8 ffffffff81ee31fd ffffffffa032f460 ffff88003387f560 [ 15.591044] ffffffff81ee46e2 0000002d00000009 0000000000000001 0000000041b58ab3 [ 15.591059] Call Trace: [ 15.591078] [] dump_stack+0x1e/0x20 [ 15.591093] [] ubsan_epilogue+0x12/0x55 [ 15.591109] [] handle_overflow+0x1ba/0x215 [ 15.591126] [] ? __ubsan_handle_negate_overflow+0x162/0x162 [ 15.591146] [] ? print_context_stack+0x9c/0x160 [ 15.591163] [] ? dump_trace+0x252/0x750 [ 15.591181] [] ? __list_add+0x93/0x160 [ 15.591197] [] __ubsan_handle_sub_overflow+0x2a/0x31 [ 15.591261] [] drm_ht_just_insert_please+0x1e0/0x200 [drm] [ 15.591290] [] ttm_base_object_init+0x10a/0x270 [ttm] [ 15.591316] [] ttm_vt_lock+0x28c/0x3a0 [ttm] [ 15.591343] [] ? ttm_write_lock+0x180/0x180 [ttm] [ 15.591362] [] ? kasan_unpoison_shadow+0x36/0x50 [ 15.591379] [] ? kasan_unpoison_shadow+0x36/0x50 [ 15.591396] [] ? kasan_unpoison_shadow+0x36/0x50 [ 15.591413] [] ? kasan_unpoison_shadow+0x36/0x50 [ 15.591442] [] vmw_master_set+0x121/0x470 [vmwgfx] [ 15.591459] [] ? __init_waitqueue_head+0x45/0x70 [ 15.591487] [] ? vmw_master_drop+0x310/0x310 [vmwgfx] [ 15.591535] [] drm_open+0x92a/0xc00 [drm] [ 15.591563] [] ? vmw_driver_open+0x170/0x170 [vmwgfx] [ 15.591610] [] ? drm_poll+0xe0/0xe0 [drm] [ 15.591661] [] drm_stub_open+0x224/0x330 [drm] [ 15.591711] [] ? drm_minor_acquire+0x240/0x240 [drm] [ 15.591727] [] chrdev_open+0x1fa/0x3f0 [ 15.591742] [] ? cdev_put+0x50/0x50 [ 15.591761] [] ? __fsnotify_parent+0x53/0x210 [ 15.591778] [] do_dentry_open+0x351/0x670 [ 15.591792] [] ? cdev_put+0x50/0x50 [ 15.591807] [] vfs_open+0xa2/0x170 [ 15.591824] [] do_last+0xccf/0x2c80 [ 15.591842] [] ? filename_create+0x320/0x320 [ 15.591858] [] ? path_init+0x1b9/0xa90 [ 15.591875] [] ? mountpoint_last+0x9a0/0x9a0 [ 15.591894] [] ? selinux_file_alloc_security+0xcf/0x130 [ 15.591911] [] path_openat+0x1e7/0xcc0 [ 15.591927] [] ? dump_trace+0x252/0x750 [ 15.591943] [] ? do_last+0x2c80/0x2c80 [ 15.591959] [] ? __list_add+0x93/0x160 [ 15.591974] [] ? save_stack_trace+0x7d/0xb0 [ 15.591989] [] do_filp_open+0xa4/0x160 [ 15.592004] [] ? user_path_mountpoint_at+0x50/0x50 [ 15.592022] [] ? __alloc_fd+0x175/0x300 [ 15.592039] [] do_sys_open+0x1b7/0x3f0 [ 15.592054] [] ? filp_open+0x80/0x80 [ 15.592070] [] SyS_open+0x32/0x40 [ 15.592088] [] system_call_fastpath+0x16/0x1b Signed-off-by: Xie XiuQi [seanpaul tweaked subject to remove "gpu/"] Signed-off-by: Sean Paul Link: http://patchwork.freedesktop.org/patch/msgid/1473152138-25335-1-git-send-email-xiexiuqi@huawei.com --- drivers/gpu/drm/drm_hashtab.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_hashtab.c b/drivers/gpu/drm/drm_hashtab.c index 7b30b307674b..dae18e58e79b 100644 --- a/drivers/gpu/drm/drm_hashtab.c +++ b/drivers/gpu/drm/drm_hashtab.c @@ -142,7 +142,7 @@ int drm_ht_just_insert_please(struct drm_open_hash *ht, struct drm_hash_item *it unsigned long add) { int ret; - unsigned long mask = (1 << bits) - 1; + unsigned long mask = (1UL << bits) - 1; unsigned long first, unshifted_key; unshifted_key = hash_long(seed, bits);