lkml.org 
[lkml]   [2021]   [Feb]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] drm/amdgpu: fix potential integer overflow on shift of a int
Date
From: Colin Ian King <colin.king@canonical.com>

The left shift of int 32 bit integer constant 1 is evaluated using 32
bit arithmetic and then assigned to an unsigned 64 bit integer. In the
case where *frag is 32 or more this can lead to an oveflow. Avoid this
by shifting 1ULL.

Addresses-Coverity: ("Unintentional integer overflow")
Fixes: dfcd99f6273e ("drm/amdgpu: meld together VM fragment and huge page handling")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 9d19078246c8..53a925600510 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1412,7 +1412,7 @@ static void amdgpu_vm_fragment(struct amdgpu_vm_update_params *params,
*frag = max_frag;
*frag_end = end & ~((1ULL << max_frag) - 1);
} else {
- *frag_end = start + (1 << *frag);
+ *frag_end = start + (1ULL << *frag);
}
}

--
2.29.2
\
 
 \ /
  Last update: 2021-02-08 00:09    [W:0.071 / U:0.084 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site