diff options
| -rw-r--r-- | block/linux-aio.c | 2 | ||||
| -rw-r--r-- | chardev/char-fd.c | 2 | ||||
| -rw-r--r-- | chardev/char-pty.c | 2 | ||||
| -rw-r--r-- | chardev/char-socket.c | 2 | ||||
| -rw-r--r-- | hw/audio/ac97.c | 4 | ||||
| -rw-r--r-- | hw/audio/cs4231a.c | 4 | ||||
| -rw-r--r-- | hw/audio/es1370.c | 2 | ||||
| -rw-r--r-- | hw/audio/gus.c | 2 | ||||
| -rw-r--r-- | hw/audio/marvell_88w8618.c | 2 | ||||
| -rw-r--r-- | hw/audio/sb16.c | 2 | ||||
| -rw-r--r-- | hw/audio/via-ac97.c | 2 | ||||
| -rw-r--r-- | hw/char/sclpconsole-lm.c | 2 | ||||
| -rw-r--r-- | hw/display/vmware_vga.c | 2 | ||||
| -rw-r--r-- | hw/dma/xlnx_csu_dma.c | 2 | ||||
| -rw-r--r-- | hw/hyperv/syndbg.c | 2 | ||||
| -rw-r--r-- | hw/misc/aspeed_hace.c | 2 | ||||
| -rw-r--r-- | hw/net/rtl8139.c | 2 | ||||
| -rw-r--r-- | hw/net/tulip.c | 2 | ||||
| -rw-r--r-- | hw/net/virtio-net.c | 6 | ||||
| -rw-r--r-- | hw/net/xgmac.c | 2 | ||||
| -rw-r--r-- | hw/nvme/ctrl.c | 6 | ||||
| -rw-r--r-- | hw/ppc/pnv_occ.c | 2 | ||||
| -rw-r--r-- | hw/ppc/spapr_tpm_proxy.c | 4 | ||||
| -rw-r--r-- | hw/scsi/lsi53c895a.c | 2 | ||||
| -rw-r--r-- | hw/scsi/megasas.c | 7 | ||||
| -rw-r--r-- | hw/ufs/lu.c | 2 | ||||
| -rw-r--r-- | hw/usb/hcd-ohci.c | 2 | ||||
| -rw-r--r-- | hw/virtio/virtio.c | 8 | ||||
| -rw-r--r-- | include/qemu/compiler.h | 20 | ||||
| -rw-r--r-- | net/socket.c | 2 | ||||
| -rw-r--r-- | net/stream.c | 2 |
31 files changed, 61 insertions, 44 deletions
diff --git a/block/linux-aio.c b/block/linux-aio.c index 407369f5c9..c200e7ad20 100644 --- a/block/linux-aio.c +++ b/block/linux-aio.c @@ -291,7 +291,7 @@ static void ioq_submit(LinuxAioState *s) { int ret, len; struct qemu_laiocb *aiocb; - struct iocb *iocbs[MAX_EVENTS]; + QEMU_UNINITIALIZED struct iocb *iocbs[MAX_EVENTS]; QSIMPLEQ_HEAD(, qemu_laiocb) completed; do { diff --git a/chardev/char-fd.c b/chardev/char-fd.c index 23bfe3c0b1..6f03adf872 100644 --- a/chardev/char-fd.c +++ b/chardev/char-fd.c @@ -50,7 +50,7 @@ static gboolean fd_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque) Chardev *chr = CHARDEV(opaque); FDChardev *s = FD_CHARDEV(opaque); int len; - uint8_t buf[CHR_READ_BUF_LEN]; + QEMU_UNINITIALIZED uint8_t buf[CHR_READ_BUF_LEN]; ssize_t ret; len = sizeof(buf); diff --git a/chardev/char-pty.c b/chardev/char-pty.c index c28554e6e0..674e9b3f14 100644 --- a/chardev/char-pty.c +++ b/chardev/char-pty.c @@ -154,7 +154,7 @@ static gboolean pty_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque) Chardev *chr = CHARDEV(opaque); PtyChardev *s = PTY_CHARDEV(opaque); gsize len; - uint8_t buf[CHR_READ_BUF_LEN]; + QEMU_UNINITIALIZED uint8_t buf[CHR_READ_BUF_LEN]; ssize_t ret; len = sizeof(buf); diff --git a/chardev/char-socket.c b/chardev/char-socket.c index e8dd2931dc..1e8313915b 100644 --- a/chardev/char-socket.c +++ b/chardev/char-socket.c @@ -497,7 +497,7 @@ static gboolean tcp_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque) { Chardev *chr = CHARDEV(opaque); SocketChardev *s = SOCKET_CHARDEV(opaque); - uint8_t buf[CHR_READ_BUF_LEN]; + QEMU_UNINITIALIZED uint8_t buf[CHR_READ_BUF_LEN]; int len, size; if ((s->state != TCP_CHARDEV_STATE_CONNECTED) || diff --git a/hw/audio/ac97.c b/hw/audio/ac97.c index 669a0463cc..eb7a847080 100644 --- a/hw/audio/ac97.c +++ b/hw/audio/ac97.c @@ -886,7 +886,7 @@ static void nabm_writel(void *opaque, uint32_t addr, uint32_t val) static int write_audio(AC97LinkState *s, AC97BusMasterRegs *r, int max, int *stop) { - uint8_t tmpbuf[4096]; + QEMU_UNINITIALIZED uint8_t tmpbuf[4096]; uint32_t addr = r->bd.addr; uint32_t temp = r->picb << 1; uint32_t written = 0; @@ -959,7 +959,7 @@ static void write_bup(AC97LinkState *s, int elapsed) static int read_audio(AC97LinkState *s, AC97BusMasterRegs *r, int max, int *stop) { - uint8_t tmpbuf[4096]; + QEMU_UNINITIALIZED uint8_t tmpbuf[4096]; uint32_t addr = r->bd.addr; uint32_t temp = r->picb << 1; uint32_t nread = 0; diff --git a/hw/audio/cs4231a.c b/hw/audio/cs4231a.c index eb9a45805b..6dfff202ff 100644 --- a/hw/audio/cs4231a.c +++ b/hw/audio/cs4231a.c @@ -528,7 +528,7 @@ static int cs_write_audio (CSState *s, int nchan, int dma_pos, int dma_len, int len) { int temp, net; - uint8_t tmpbuf[4096]; + QEMU_UNINITIALIZED uint8_t tmpbuf[4096]; IsaDmaClass *k = ISADMA_GET_CLASS(s->isa_dma); temp = len; @@ -547,7 +547,7 @@ static int cs_write_audio (CSState *s, int nchan, int dma_pos, copied = k->read_memory(s->isa_dma, nchan, tmpbuf, dma_pos, to_copy); if (s->tab) { int i; - int16_t linbuf[4096]; + QEMU_UNINITIALIZED int16_t linbuf[4096]; for (i = 0; i < copied; ++i) linbuf[i] = s->tab[tmpbuf[i]]; diff --git a/hw/audio/es1370.c b/hw/audio/es1370.c index 8efb969212..a6a32a6348 100644 --- a/hw/audio/es1370.c +++ b/hw/audio/es1370.c @@ -604,7 +604,7 @@ static uint64_t es1370_read(void *opaque, hwaddr addr, unsigned size) static void es1370_transfer_audio (ES1370State *s, struct chan *d, int loop_sel, int max, bool *irq) { - uint8_t tmpbuf[4096]; + QEMU_UNINITIALIZED uint8_t tmpbuf[4096]; size_t to_transfer; uint32_t addr = d->frame_addr; int sc = d->scount & 0xffff; diff --git a/hw/audio/gus.c b/hw/audio/gus.c index 87e8634893..c36df0240f 100644 --- a/hw/audio/gus.c +++ b/hw/audio/gus.c @@ -183,7 +183,7 @@ static int GUS_read_DMA (void *opaque, int nchan, int dma_pos, int dma_len) { GUSState *s = opaque; IsaDmaClass *k = ISADMA_GET_CLASS(s->isa_dma); - char tmpbuf[4096]; + QEMU_UNINITIALIZED char tmpbuf[4096]; int pos = dma_pos, mode, left = dma_len - dma_pos; ldebug ("read DMA %#x %d\n", dma_pos, dma_len); diff --git a/hw/audio/marvell_88w8618.c b/hw/audio/marvell_88w8618.c index 6d3ebbb0c8..c5c79d083a 100644 --- a/hw/audio/marvell_88w8618.c +++ b/hw/audio/marvell_88w8618.c @@ -66,7 +66,7 @@ static void mv88w8618_audio_callback(void *opaque, int free_out, int free_in) { mv88w8618_audio_state *s = opaque; int16_t *codec_buffer; - int8_t buf[4096]; + QEMU_UNINITIALIZED int8_t buf[4096]; int8_t *mem_buffer; int pos, block_size; diff --git a/hw/audio/sb16.c b/hw/audio/sb16.c index 19fd3b9020..bac64118fe 100644 --- a/hw/audio/sb16.c +++ b/hw/audio/sb16.c @@ -1181,7 +1181,7 @@ static int write_audio (SB16State *s, int nchan, int dma_pos, IsaDma *isa_dma = nchan == s->dma ? s->isa_dma : s->isa_hdma; IsaDmaClass *k = ISADMA_GET_CLASS(isa_dma); int temp, net; - uint8_t tmpbuf[4096]; + QEMU_UNINITIALIZED uint8_t tmpbuf[4096]; temp = len; net = 0; diff --git a/hw/audio/via-ac97.c b/hw/audio/via-ac97.c index 1e0a5c7398..d5231e1cf2 100644 --- a/hw/audio/via-ac97.c +++ b/hw/audio/via-ac97.c @@ -175,7 +175,7 @@ static void out_cb(void *opaque, int avail) ViaAC97SGDChannel *c = &s->aur; int temp, to_copy, copied; bool stop = false; - uint8_t tmpbuf[4096]; + QEMU_UNINITIALIZED uint8_t tmpbuf[4096]; if (c->stat & STAT_PAUSED) { return; diff --git a/hw/char/sclpconsole-lm.c b/hw/char/sclpconsole-lm.c index e9580aacba..3e40d5e434 100644 --- a/hw/char/sclpconsole-lm.c +++ b/hw/char/sclpconsole-lm.c @@ -214,7 +214,7 @@ static int process_mdb(SCLPEvent *event, MDBO *mdbo) { int rc; int len; - uint8_t buffer[SIZE_BUFFER]; + QEMU_UNINITIALIZED uint8_t buffer[SIZE_BUFFER]; len = be16_to_cpu(mdbo->length); len -= sizeof(mdbo->length) + sizeof(mdbo->type) diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c index 544bb65320..bc1a8ed466 100644 --- a/hw/display/vmware_vga.c +++ b/hw/display/vmware_vga.c @@ -618,7 +618,7 @@ static void vmsvga_fifo_run(struct vmsvga_state_s *s) uint32_t cmd, colour; int args, len, maxloop = 1024; int x, y, dx, dy, width, height; - struct vmsvga_cursor_definition_s cursor; + QEMU_UNINITIALIZED struct vmsvga_cursor_definition_s cursor; uint32_t cmd_start; len = vmsvga_fifo_length(s); diff --git a/hw/dma/xlnx_csu_dma.c b/hw/dma/xlnx_csu_dma.c index 3db3904d83..d8c7da1a50 100644 --- a/hw/dma/xlnx_csu_dma.c +++ b/hw/dma/xlnx_csu_dma.c @@ -287,7 +287,7 @@ static uint32_t xlnx_csu_dma_advance(XlnxCSUDMA *s, uint32_t len) static void xlnx_csu_dma_src_notify(void *opaque) { XlnxCSUDMA *s = XLNX_CSU_DMA(opaque); - unsigned char buf[4 * 1024]; + QEMU_UNINITIALIZED unsigned char buf[4 * 1024]; size_t rlen = 0; ptimer_transaction_begin(s->src_timer); diff --git a/hw/hyperv/syndbg.c b/hw/hyperv/syndbg.c index 8b8a14750d..ac7e15f6f1 100644 --- a/hw/hyperv/syndbg.c +++ b/hw/hyperv/syndbg.c @@ -192,7 +192,7 @@ static uint16_t handle_recv_msg(HvSynDbg *syndbg, uint64_t outgpa, { uint16_t ret; g_assert(MSG_BUFSZ >= qemu_target_page_size()); - uint8_t data_buf[MSG_BUFSZ]; + QEMU_UNINITIALIZED uint8_t data_buf[MSG_BUFSZ]; hwaddr out_len; void *out_data; ssize_t recv_byte_count; diff --git a/hw/misc/aspeed_hace.c b/hw/misc/aspeed_hace.c index 8924a30eff..726368fbbc 100644 --- a/hw/misc/aspeed_hace.c +++ b/hw/misc/aspeed_hace.c @@ -419,7 +419,7 @@ static void hash_execute_acc_mode(AspeedHACEState *s, int algo, static void do_hash_operation(AspeedHACEState *s, int algo, bool sg_mode, bool acc_mode) { - struct iovec iov[ASPEED_HACE_MAX_SG]; + QEMU_UNINITIALIZED struct iovec iov[ASPEED_HACE_MAX_SG]; bool acc_final_request = false; int iov_idx = -1; diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c index 15b8f7501a..654a087d80 100644 --- a/hw/net/rtl8139.c +++ b/hw/net/rtl8139.c @@ -1816,7 +1816,7 @@ static int rtl8139_transmit_one(RTL8139State *s, int descriptor) PCIDevice *d = PCI_DEVICE(s); int txsize = s->TxStatus[descriptor] & 0x1fff; - uint8_t txbuffer[0x2000]; + QEMU_UNINITIALIZED uint8_t txbuffer[0x2000]; DPRINTF("+++ transmit reading %d bytes from host memory at 0x%08x\n", txsize, s->TxAddr[descriptor]); diff --git a/hw/net/tulip.c b/hw/net/tulip.c index 63fe513458..319af906c8 100644 --- a/hw/net/tulip.c +++ b/hw/net/tulip.c @@ -629,7 +629,7 @@ static void tulip_setup_filter_addr(TULIPState *s, uint8_t *buf, int n) static void tulip_setup_frame(TULIPState *s, struct tulip_descriptor *desc) { - uint8_t buf[4096]; + QEMU_UNINITIALIZED uint8_t buf[4096]; int len = (desc->control >> TDES1_BUF1_SIZE_SHIFT) & TDES1_BUF1_SIZE_MASK; int i; diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 221252e00a..eb93607b8c 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -1911,9 +1911,9 @@ static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf, VirtIONet *n = qemu_get_nic_opaque(nc); VirtIONetQueue *q; VirtIODevice *vdev = VIRTIO_DEVICE(n); - VirtQueueElement *elems[VIRTQUEUE_MAX_SIZE]; - size_t lens[VIRTQUEUE_MAX_SIZE]; - struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE]; + QEMU_UNINITIALIZED VirtQueueElement *elems[VIRTQUEUE_MAX_SIZE]; + QEMU_UNINITIALIZED size_t lens[VIRTQUEUE_MAX_SIZE]; + QEMU_UNINITIALIZED struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE]; struct virtio_net_hdr_v1_hash extra_hdr; unsigned mhdr_cnt = 0; size_t offset, i, guest_offset, j; diff --git a/hw/net/xgmac.c b/hw/net/xgmac.c index 9c87c4e70f..d45f872467 100644 --- a/hw/net/xgmac.c +++ b/hw/net/xgmac.c @@ -207,7 +207,7 @@ static void xgmac_enet_send(XgmacState *s) struct desc bd; int frame_size; int len; - uint8_t frame[8192]; + QEMU_UNINITIALIZED uint8_t frame[8192]; uint8_t *ptr; ptr = frame; diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c index fd935507bc..220002830d 100644 --- a/hw/nvme/ctrl.c +++ b/hw/nvme/ctrl.c @@ -1057,7 +1057,8 @@ static uint16_t nvme_map_sgl(NvmeCtrl *n, NvmeSg *sg, NvmeSglDescriptor sgl, */ #define SEG_CHUNK_SIZE 256 - NvmeSglDescriptor segment[SEG_CHUNK_SIZE], *sgld, *last_sgld; + QEMU_UNINITIALIZED NvmeSglDescriptor segment[SEG_CHUNK_SIZE]; + NvmeSglDescriptor *sgld, *last_sgld; uint64_t nsgld; uint32_t seg_len; uint16_t status; @@ -5128,7 +5129,7 @@ static uint16_t nvme_error_info(NvmeCtrl *n, uint8_t rae, uint32_t buf_len, static uint16_t nvme_changed_nslist(NvmeCtrl *n, uint8_t rae, uint32_t buf_len, uint64_t off, NvmeRequest *req) { - uint32_t nslist[1024]; + uint32_t nslist[1024] = {}; uint32_t trans_len; int i = 0; uint32_t nsid; @@ -5138,7 +5139,6 @@ static uint16_t nvme_changed_nslist(NvmeCtrl *n, uint8_t rae, uint32_t buf_len, return NVME_INVALID_FIELD | NVME_DNR; } - memset(nslist, 0x0, sizeof(nslist)); trans_len = MIN(sizeof(nslist) - off, buf_len); while ((nsid = find_first_bit(n->changed_nsids, NVME_CHANGED_NSID_SIZE)) != diff --git a/hw/ppc/pnv_occ.c b/hw/ppc/pnv_occ.c index fa6f31cb8d..24b789c191 100644 --- a/hw/ppc/pnv_occ.c +++ b/hw/ppc/pnv_occ.c @@ -789,7 +789,7 @@ static bool occ_opal_process_command(PnvOCC *occ, static bool occ_model_tick(PnvOCC *occ) { - struct occ_dynamic_data dynamic_data; + QEMU_UNINITIALIZED struct occ_dynamic_data dynamic_data; if (!occ_read_dynamic_data(occ, &dynamic_data, NULL)) { /* Can't move OCC state field to safe because we can't map it! */ diff --git a/hw/ppc/spapr_tpm_proxy.c b/hw/ppc/spapr_tpm_proxy.c index 862eeaa50a..1297b3ad56 100644 --- a/hw/ppc/spapr_tpm_proxy.c +++ b/hw/ppc/spapr_tpm_proxy.c @@ -41,8 +41,8 @@ static ssize_t tpm_execute(SpaprTpmProxy *tpm_proxy, target_ulong *args) target_ulong data_in_size = args[2]; uint64_t data_out = ppc64_phys_to_real(args[3]); target_ulong data_out_size = args[4]; - uint8_t buf_in[TPM_SPAPR_BUFSIZE]; - uint8_t buf_out[TPM_SPAPR_BUFSIZE]; + QEMU_UNINITIALIZED uint8_t buf_in[TPM_SPAPR_BUFSIZE]; + QEMU_UNINITIALIZED uint8_t buf_out[TPM_SPAPR_BUFSIZE]; ssize_t ret; trace_spapr_tpm_execute(data_in, data_in_size, data_out, data_out_size); diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c index f4f2ef321e..9ea4aa0a85 100644 --- a/hw/scsi/lsi53c895a.c +++ b/hw/scsi/lsi53c895a.c @@ -1112,7 +1112,7 @@ bad: static void lsi_memcpy(LSIState *s, uint32_t dest, uint32_t src, int count) { int n; - uint8_t buf[LSI_BUF_SIZE]; + QEMU_UNINITIALIZED uint8_t buf[LSI_BUF_SIZE]; trace_lsi_memcpy(dest, src, count); while (count) { diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c index 55cd188bd5..844643d916 100644 --- a/hw/scsi/megasas.c +++ b/hw/scsi/megasas.c @@ -981,13 +981,11 @@ static int megasas_event_wait(MegasasState *s, MegasasCmd *cmd) static int megasas_dcmd_pd_get_list(MegasasState *s, MegasasCmd *cmd) { - struct mfi_pd_list info; - size_t dcmd_size = sizeof(info); + struct mfi_pd_list info = {}; BusChild *kid; uint32_t offset, dcmd_limit, num_pd_disks = 0, max_pd_disks; dma_addr_t residual; - memset(&info, 0, dcmd_size); offset = 8; dcmd_limit = offset + sizeof(struct mfi_pd_address); if (cmd->iov_size < dcmd_limit) { @@ -1429,11 +1427,10 @@ static int megasas_dcmd_cfg_read(MegasasState *s, MegasasCmd *cmd) static int megasas_dcmd_get_properties(MegasasState *s, MegasasCmd *cmd) { - struct mfi_ctrl_props info; + struct mfi_ctrl_props info = {}; size_t dcmd_size = sizeof(info); dma_addr_t residual; - memset(&info, 0x0, dcmd_size); if (cmd->iov_size < dcmd_size) { trace_megasas_dcmd_invalid_xfer_len(cmd->index, cmd->iov_size, dcmd_size); diff --git a/hw/ufs/lu.c b/hw/ufs/lu.c index 57b307ea56..2d8ffd72c5 100644 --- a/hw/ufs/lu.c +++ b/hw/ufs/lu.c @@ -194,7 +194,7 @@ static int ufs_emulate_wlun_inquiry(UfsRequest *req, uint8_t *outbuf, static UfsReqResult ufs_emulate_scsi_cmd(UfsLu *lu, UfsRequest *req) { uint8_t lun = lu->lun; - uint8_t outbuf[4096]; + QEMU_UNINITIALIZED uint8_t outbuf[4096]; uint8_t sense_buf[UFS_SENSE_SIZE]; uint8_t scsi_status; int len = 0; diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c index 71b54914d3..72a9f9f474 100644 --- a/hw/usb/hcd-ohci.c +++ b/hw/usb/hcd-ohci.c @@ -577,7 +577,7 @@ static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed) USBDevice *dev; USBEndpoint *ep; USBPacket *pkt; - uint8_t buf[8192]; + QEMU_UNINITIALIZED uint8_t buf[8192]; bool int_req; struct ohci_iso_td iso_td; uint32_t addr; diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 5534251e01..82a285a31d 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -1689,8 +1689,8 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t sz) VirtIODevice *vdev = vq->vdev; VirtQueueElement *elem = NULL; unsigned out_num, in_num, elem_entries; - hwaddr addr[VIRTQUEUE_MAX_SIZE]; - struct iovec iov[VIRTQUEUE_MAX_SIZE]; + hwaddr QEMU_UNINITIALIZED addr[VIRTQUEUE_MAX_SIZE]; + struct iovec QEMU_UNINITIALIZED iov[VIRTQUEUE_MAX_SIZE]; VRingDesc desc; int rc; @@ -1836,8 +1836,8 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t sz) VirtIODevice *vdev = vq->vdev; VirtQueueElement *elem = NULL; unsigned out_num, in_num, elem_entries; - hwaddr addr[VIRTQUEUE_MAX_SIZE]; - struct iovec iov[VIRTQUEUE_MAX_SIZE]; + hwaddr QEMU_UNINITIALIZED addr[VIRTQUEUE_MAX_SIZE]; + struct iovec QEMU_UNINITIALIZED iov[VIRTQUEUE_MAX_SIZE]; VRingPackedDesc desc; uint16_t id; int rc; diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h index 496dac5ac1..65b89958d3 100644 --- a/include/qemu/compiler.h +++ b/include/qemu/compiler.h @@ -208,6 +208,26 @@ #endif /* + * Disable -ftrivial-auto-var-init on a local variable. + * + * Use this in cases where there a method in the device I/O path (or other + * important hot paths), that has large variables on the stack. A rule of + * thumb is that "large" means a method with 4kb data in the local stack + * frame. Any variables which are KB in size, should be annotated with this + * attribute, to pre-emptively eliminate any potential overhead from the + * compiler's implicit zero'ing of memory. + * + * Given that this turns off a security hardening feature, when using this + * to flag variables, it is important that the code is double-checked to + * ensure there is no possible use of uninitialized data in the method. + */ +#if __has_attribute(uninitialized) +# define QEMU_UNINITIALIZED __attribute__((uninitialized)) +#else +# define QEMU_UNINITIALIZED +#endif + +/* * http://clang.llvm.org/docs/ThreadSafetyAnalysis.html * * TSA is available since clang 3.6-ish. diff --git a/net/socket.c b/net/socket.c index 8e3702e1f3..784dda686f 100644 --- a/net/socket.c +++ b/net/socket.c @@ -157,7 +157,7 @@ static void net_socket_send(void *opaque) NetSocketState *s = opaque; int size; int ret; - uint8_t buf1[NET_BUFSIZE]; + QEMU_UNINITIALIZED uint8_t buf1[NET_BUFSIZE]; const uint8_t *buf; size = recv(s->fd, buf1, sizeof(buf1), 0); diff --git a/net/stream.c b/net/stream.c index 4de5613844..6152d2a05e 100644 --- a/net/stream.c +++ b/net/stream.c @@ -148,7 +148,7 @@ static gboolean net_stream_send(QIOChannel *ioc, NetStreamState *s = data; int size; int ret; - char buf1[NET_BUFSIZE]; + QEMU_UNINITIALIZED char buf1[NET_BUFSIZE]; const char *buf; size = qio_channel_read(s->ioc, buf1, sizeof(buf1), NULL); |