From: Jeremy Kerr <jk@xxxxxxxxxx> [ Upstream commit 88413a6bfbbe2f648df399b62f85c934460b7a4d ] Currently, we may perform a copy_to_user (through simple_read_from_buffer()) while holding a context's register_lock, while accessing the context save area. This change uses a temporary buffer for the context save area data, which we then pass to simple_read_from_buffer. Includes changes from Christoph Hellwig <hch@xxxxxx>. Fixes: bf1ab978be23 ("[POWERPC] coredump: Add SPU elf notes to coredump.") Signed-off-by: Jeremy Kerr <jk@xxxxxxxxxx> Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx> [hch: renamed to function to avoid ___-prefixes] Signed-off-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/powerpc/platforms/cell/spufs/file.c | 113 +++++++++++++++-------- 1 file changed, 75 insertions(+), 38 deletions(-) diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c index 5038fd578e65..e708c163fd6d 100644 --- a/arch/powerpc/platforms/cell/spufs/file.c +++ b/arch/powerpc/platforms/cell/spufs/file.c @@ -2044,8 +2044,9 @@ static ssize_t __spufs_mbox_info_read(struct spu_context *ctx, static ssize_t spufs_mbox_info_read(struct file *file, char __user *buf, size_t len, loff_t *pos) { - int ret; struct spu_context *ctx = file->private_data; + u32 stat, data; + int ret; if (!access_ok(VERIFY_WRITE, buf, len)) return -EFAULT; @@ -2054,11 +2055,16 @@ static ssize_t spufs_mbox_info_read(struct file *file, char __user *buf, if (ret) return ret; spin_lock(&ctx->csa.register_lock); - ret = __spufs_mbox_info_read(ctx, buf, len, pos); + stat = ctx->csa.prob.mb_stat_R; + data = ctx->csa.prob.pu_mb_R; spin_unlock(&ctx->csa.register_lock); spu_release_saved(ctx); - return ret; + /* EOF if there's no entry in the mbox */ + if (!(stat & 0x0000ff)) + return 0; + + return simple_read_from_buffer(buf, len, pos, &data, sizeof(data)); } static const struct file_operations spufs_mbox_info_fops = { @@ -2085,6 +2091,7 @@ static ssize_t spufs_ibox_info_read(struct file *file, char __user *buf, size_t len, loff_t *pos) { struct spu_context *ctx = file->private_data; + u32 stat, data; int ret; if (!access_ok(VERIFY_WRITE, buf, len)) @@ -2094,11 +2101,16 @@ static ssize_t spufs_ibox_info_read(struct file *file, char __user *buf, if (ret) return ret; spin_lock(&ctx->csa.register_lock); - ret = __spufs_ibox_info_read(ctx, buf, len, pos); + stat = ctx->csa.prob.mb_stat_R; + data = ctx->csa.priv2.puint_mb_R; spin_unlock(&ctx->csa.register_lock); spu_release_saved(ctx); - return ret; + /* EOF if there's no entry in the ibox */ + if (!(stat & 0xff0000)) + return 0; + + return simple_read_from_buffer(buf, len, pos, &data, sizeof(data)); } static const struct file_operations spufs_ibox_info_fops = { @@ -2107,6 +2119,11 @@ static const struct file_operations spufs_ibox_info_fops = { .llseek = generic_file_llseek, }; +static size_t spufs_wbox_info_cnt(struct spu_context *ctx) +{ + return (4 - ((ctx->csa.prob.mb_stat_R & 0x00ff00) >> 8)) * sizeof(u32); +} + static ssize_t __spufs_wbox_info_read(struct spu_context *ctx, char __user *buf, size_t len, loff_t *pos) { @@ -2115,7 +2132,7 @@ static ssize_t __spufs_wbox_info_read(struct spu_context *ctx, u32 wbox_stat; wbox_stat = ctx->csa.prob.mb_stat_R; - cnt = 4 - ((wbox_stat & 0x00ff00) >> 8); + cnt = spufs_wbox_info_cnt(ctx); for (i = 0; i < cnt; i++) { data[i] = ctx->csa.spu_mailbox_data[i]; } @@ -2128,7 +2145,8 @@ static ssize_t spufs_wbox_info_read(struct file *file, char __user *buf, size_t len, loff_t *pos) { struct spu_context *ctx = file->private_data; - int ret; + u32 data[ARRAY_SIZE(ctx->csa.spu_mailbox_data)]; + int ret, count; if (!access_ok(VERIFY_WRITE, buf, len)) return -EFAULT; @@ -2137,11 +2155,13 @@ static ssize_t spufs_wbox_info_read(struct file *file, char __user *buf, if (ret) return ret; spin_lock(&ctx->csa.register_lock); - ret = __spufs_wbox_info_read(ctx, buf, len, pos); + count = spufs_wbox_info_cnt(ctx); + memcpy(&data, &ctx->csa.spu_mailbox_data, sizeof(data)); spin_unlock(&ctx->csa.register_lock); spu_release_saved(ctx); - return ret; + return simple_read_from_buffer(buf, len, pos, &data, + count * sizeof(u32)); } static const struct file_operations spufs_wbox_info_fops = { @@ -2150,27 +2170,33 @@ static const struct file_operations spufs_wbox_info_fops = { .llseek = generic_file_llseek, }; -static ssize_t __spufs_dma_info_read(struct spu_context *ctx, - char __user *buf, size_t len, loff_t *pos) +static void spufs_get_dma_info(struct spu_context *ctx, + struct spu_dma_info *info) { - struct spu_dma_info info; - struct mfc_cq_sr *qp, *spuqp; int i; - info.dma_info_type = ctx->csa.priv2.spu_tag_status_query_RW; - info.dma_info_mask = ctx->csa.lscsa->tag_mask.slot[0]; - info.dma_info_status = ctx->csa.spu_chnldata_RW[24]; - info.dma_info_stall_and_notify = ctx->csa.spu_chnldata_RW[25]; - info.dma_info_atomic_command_status = ctx->csa.spu_chnldata_RW[27]; + info->dma_info_type = ctx->csa.priv2.spu_tag_status_query_RW; + info->dma_info_mask = ctx->csa.lscsa->tag_mask.slot[0]; + info->dma_info_status = ctx->csa.spu_chnldata_RW[24]; + info->dma_info_stall_and_notify = ctx->csa.spu_chnldata_RW[25]; + info->dma_info_atomic_command_status = ctx->csa.spu_chnldata_RW[27]; for (i = 0; i < 16; i++) { - qp = &info.dma_info_command_data[i]; - spuqp = &ctx->csa.priv2.spuq[i]; + struct mfc_cq_sr *qp = &info->dma_info_command_data[i]; + struct mfc_cq_sr *spuqp = &ctx->csa.priv2.spuq[i]; qp->mfc_cq_data0_RW = spuqp->mfc_cq_data0_RW; qp->mfc_cq_data1_RW = spuqp->mfc_cq_data1_RW; qp->mfc_cq_data2_RW = spuqp->mfc_cq_data2_RW; qp->mfc_cq_data3_RW = spuqp->mfc_cq_data3_RW; } +} + +static ssize_t __spufs_dma_info_read(struct spu_context *ctx, + char __user *buf, size_t len, loff_t *pos) +{ + struct spu_dma_info info; + + spufs_get_dma_info(ctx, &info); return simple_read_from_buffer(buf, len, pos, &info, sizeof info); @@ -2180,6 +2206,7 @@ static ssize_t spufs_dma_info_read(struct file *file, char __user *buf, size_t len, loff_t *pos) { struct spu_context *ctx = file->private_data; + struct spu_dma_info info; int ret; if (!access_ok(VERIFY_WRITE, buf, len)) @@ -2189,11 +2216,12 @@ static ssize_t spufs_dma_info_read(struct file *file, char __user *buf, if (ret) return ret; spin_lock(&ctx->csa.register_lock); - ret = __spufs_dma_info_read(ctx, buf, len, pos); + spufs_get_dma_info(ctx, &info); spin_unlock(&ctx->csa.register_lock); spu_release_saved(ctx); - return ret; + return simple_read_from_buffer(buf, len, pos, &info, + sizeof(info)); } static const struct file_operations spufs_dma_info_fops = { @@ -2202,13 +2230,31 @@ static const struct file_operations spufs_dma_info_fops = { .llseek = no_llseek, }; +static void spufs_get_proxydma_info(struct spu_context *ctx, + struct spu_proxydma_info *info) +{ + int i; + + info->proxydma_info_type = ctx->csa.prob.dma_querytype_RW; + info->proxydma_info_mask = ctx->csa.prob.dma_querymask_RW; + info->proxydma_info_status = ctx->csa.prob.dma_tagstatus_R; + + for (i = 0; i < 8; i++) { + struct mfc_cq_sr *qp = &info->proxydma_info_command_data[i]; + struct mfc_cq_sr *puqp = &ctx->csa.priv2.puq[i]; + + qp->mfc_cq_data0_RW = puqp->mfc_cq_data0_RW; + qp->mfc_cq_data1_RW = puqp->mfc_cq_data1_RW; + qp->mfc_cq_data2_RW = puqp->mfc_cq_data2_RW; + qp->mfc_cq_data3_RW = puqp->mfc_cq_data3_RW; + } +} + static ssize_t __spufs_proxydma_info_read(struct spu_context *ctx, char __user *buf, size_t len, loff_t *pos) { struct spu_proxydma_info info; - struct mfc_cq_sr *qp, *puqp; int ret = sizeof info; - int i; if (len < ret) return -EINVAL; @@ -2216,18 +2262,7 @@ static ssize_t __spufs_proxydma_info_read(struct spu_context *ctx, if (!access_ok(VERIFY_WRITE, buf, len)) return -EFAULT; - info.proxydma_info_type = ctx->csa.prob.dma_querytype_RW; - info.proxydma_info_mask = ctx->csa.prob.dma_querymask_RW; - info.proxydma_info_status = ctx->csa.prob.dma_tagstatus_R; - for (i = 0; i < 8; i++) { - qp = &info.proxydma_info_command_data[i]; - puqp = &ctx->csa.priv2.puq[i]; - - qp->mfc_cq_data0_RW = puqp->mfc_cq_data0_RW; - qp->mfc_cq_data1_RW = puqp->mfc_cq_data1_RW; - qp->mfc_cq_data2_RW = puqp->mfc_cq_data2_RW; - qp->mfc_cq_data3_RW = puqp->mfc_cq_data3_RW; - } + spufs_get_proxydma_info(ctx, &info); return simple_read_from_buffer(buf, len, pos, &info, sizeof info); @@ -2237,17 +2272,19 @@ static ssize_t spufs_proxydma_info_read(struct file *file, char __user *buf, size_t len, loff_t *pos) { struct spu_context *ctx = file->private_data; + struct spu_proxydma_info info; int ret; ret = spu_acquire_saved(ctx); if (ret) return ret; spin_lock(&ctx->csa.register_lock); - ret = __spufs_proxydma_info_read(ctx, buf, len, pos); + spufs_get_proxydma_info(ctx, &info); spin_unlock(&ctx->csa.register_lock); spu_release_saved(ctx); - return ret; + return simple_read_from_buffer(buf, len, pos, &info, + sizeof(info)); } static const struct file_operations spufs_proxydma_info_fops = { -- 2.25.1