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path: root/ui/vnc-enc-zlib.c
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2019-09-17vnc: fix memory leak when vnc disconnectLi Qiang
Currently when qemu receives a vnc connect, it creates a 'VncState' to represent this connection. In 'vnc_worker_thread_loop' it creates a local 'VncState'. The connection 'VcnState' and local 'VncState' exchange data in 'vnc_async_encoding_start' and 'vnc_async_encoding_end'. In 'zrle_compress_data' it calls 'deflateInit2' to allocate the libz library opaque data. The 'VncState' used in 'zrle_compress_data' is the local 'VncState'. In 'vnc_zrle_clear' it calls 'deflateEnd' to free the libz library opaque data. The 'VncState' used in 'vnc_zrle_clear' is the connection 'VncState'. In currently implementation there will be a memory leak when the vnc disconnect. Following is the asan output backtrack: Direct leak of 29760 byte(s) in 5 object(s) allocated from: 0 0xffffa67ef3c3 in __interceptor_calloc (/lib64/libasan.so.4+0xd33c3) 1 0xffffa65071cb in g_malloc0 (/lib64/libglib-2.0.so.0+0x571cb) 2 0xffffa5e968f7 in deflateInit2_ (/lib64/libz.so.1+0x78f7) 3 0xaaaacec58613 in zrle_compress_data ui/vnc-enc-zrle.c:87 4 0xaaaacec58613 in zrle_send_framebuffer_update ui/vnc-enc-zrle.c:344 5 0xaaaacec34e77 in vnc_send_framebuffer_update ui/vnc.c:919 6 0xaaaacec5e023 in vnc_worker_thread_loop ui/vnc-jobs.c:271 7 0xaaaacec5e5e7 in vnc_worker_thread ui/vnc-jobs.c:340 8 0xaaaacee4d3c3 in qemu_thread_start util/qemu-thread-posix.c:502 9 0xffffa544e8bb in start_thread (/lib64/libpthread.so.0+0x78bb) 10 0xffffa53965cb in thread_start (/lib64/libc.so.6+0xd55cb) This is because the opaque allocated in 'deflateInit2' is not freed in 'deflateEnd'. The reason is that the 'deflateEnd' calls 'deflateStateCheck' and in the latter will check whether 's->strm != strm'(libz's data structure). This check will be true so in 'deflateEnd' it just return 'Z_STREAM_ERROR' and not free the data allocated in 'deflateInit2'. The reason this happens is that the 'VncState' contains the whole 'VncZrle', so when calling 'deflateInit2', the 's->strm' will be the local address. So 's->strm != strm' will be true. To fix this issue, we need to make 'zrle' of 'VncState' to be a pointer. Then the connection 'VncState' and local 'VncState' exchange mechanism will work as expection. The 'tight' of 'VncState' has the same issue, let's also turn it to a pointer. Reported-by: Ying Fang <fangying1@huawei.com> Signed-off-by: Li Qiang <liq3ea@163.com> Message-id: 20190831153922.121308-1-liq3ea@163.com Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-02-04ui: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1454089805-5470-2-git-send-email-peter.maydell@linaro.org
2011-08-20Use glib memory allocation and free functionsAnthony Liguori
qemu_malloc/qemu_free no longer exist after this commit. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-04-10vnc: tight: Fix crash after 2GB of outputMichael Tokarev
fix 2Gb integer overflow in in VNC tight and zlib encodings As found by Roland Dreier <roland@purestorage.com> (excellent catch!), when amount of VNC compressed data produced by zlib and sent to client exceeds 2Gb, integer overflow occurs because currently, we calculate amount of data produced at each step by comparing saved total_out with new total_out, and total_out is something which grows without bounds. Compare it with previous avail_out instead of total_out, and leave total_out alone. The same code is used in vnc-enc-tight.c and vnc-enc-zlib.c, so fix both cases. There, there's no actual need to save previous_out value, since capacity-offset (which is how that value is calculated) stays the same so it can be recalculated again after call to deflate(), but whole thing becomes less readable this way. Reported-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> Signed-off-by: Corentin Chary <corentin.chary@gmail.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-26vnc: encapsulate encoding membersCorentin Chary
This will allow to implement the threaded VNC server in a more cleaner way. Signed-off-by: Corentin Chary <corentincj@iksaif.net> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-07-26vnc: rename vnc-encoding-* vnc-enc-*Corentin Chary
For the same reason that we don't use vnc-authentication-sasl.c but vnc-auth-sals.c. Because it's tooooo long. Signed-off-by: Corentin Chary <corentincj@iksaif.net> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>