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Kernel: Reading from negative offset in fb dev gives out info

This commit is contained in:
Bananymous 2023-11-28 23:47:49 +02:00
parent 09b7cb2f33
commit d86ecf4f61
2 changed files with 32 additions and 1 deletions
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14
kernel/kernel/Device/FramebufferDevice.cpp
View File

@ -82,8 +82,20 @@ namespace Kernel
BAN::ErrorOr<size_t> FramebufferDevice::read_impl(off_t offset, BAN::ByteSpan buffer)
{
// Reading from negative offset will fill buffer with framebuffer info
if (offset < 0)
return BAN::Error::from_errno(EINVAL);
{
if (buffer.size() < sizeof(framebuffer_info_t))
return BAN::Error::from_errno(ENOBUFS);
auto& fb_info = buffer.as<framebuffer_info_t>();
fb_info.width = m_width;
fb_info.height = m_height;
fb_info.bpp = m_bpp;
return sizeof(framebuffer_info_t);
}
if ((size_t)offset >= m_width * m_height * bytes_per_pixel_internal)
return 0;

19
libc/include/sys/framebuffer.h Normal file
View File

@ -0,0 +1,19 @@
#ifndef _FRAMEBUFFER_H
#define _FRAMEBUFFER_H 1
#include <sys/cdefs.h>
__BEGIN_DECLS
#include <stdint.h>
struct framebuffer_info_t
{
uint32_t width;
uint32_t height;
uint8_t bpp;
};
__END_DECLS
#endif