From: Benjamin Cheng Date: Mon, 13 Apr 2026 13:22:15 +0000 (-0400) Subject: drm/amdgpu/vcn4: Avoid overflow on msg bound check X-Git-Tag: v7.1-rc2~7^2~1^2~7 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=65bce27ea6192320448c30267ffc17ffa094e713;p=thirdparty%2Fkernel%2Flinux.git drm/amdgpu/vcn4: Avoid overflow on msg bound check As pointed out by SDL, the previous condition may be vulnerable to overflow. Fixes: 0a78f2bac142 ("drm/amdgpu/vcn4: Prevent OOB reads when parsing dec msg") Cc: SDL Signed-off-by: Benjamin Cheng Reviewed-by: Ruijing Dong Signed-off-by: Alex Deucher (cherry picked from commit 3c5367d950140d4ec7af830b2268a5a6fdaa3885) --- diff --git a/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c b/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c index bbdd017cbafb..ff7269bafae8 100644 --- a/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c +++ b/drivers/gpu/drm/amd/amdgpu/vcn_v4_0.c @@ -1889,6 +1889,7 @@ static int vcn_v4_0_dec_msg(struct amdgpu_cs_parser *p, struct amdgpu_job *job, for (i = 0, msg = &msg[6]; i < num_buffers; ++i, msg += 4) { uint32_t offset, size, *create; + uint64_t buf_end; if (msg[0] != RDECODE_MESSAGE_CREATE) continue; @@ -1896,7 +1897,8 @@ static int vcn_v4_0_dec_msg(struct amdgpu_cs_parser *p, struct amdgpu_job *job, offset = msg[1]; size = msg[2]; - if (size < 4 || offset + size > end - addr) { + if (size < 4 || check_add_overflow(offset, size, &buf_end) || + buf_end > end - addr) { DRM_ERROR("VCN message buffer exceeds BO bounds!\n"); r = -EINVAL; goto out;