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authorMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-19 23:01:26 +0200
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-19 23:37:01 +0200
commit2ae782ca839e0ee07de37122ddea362adff2e975 (patch)
treedf6b1a190760f51465122ca4c13492d5ac5984c6 /mm/mincore.c
parent0a8ab17689e628c84a666195bfc6ab85d11cf057 (diff)
parent0661b3d6cfd774e28a2e2ba90a3d87479e5c399b (diff)
Merge tag 'v4.9.220' into 4.9-2.3.x-imx
This is the 4.9.220 stable release Conflicts: arch/arm/Kconfig.debug arch/arm/boot/dts/imx7s.dtsi arch/arm/mach-imx/common.h arch/arm/mach-imx/cpuidle-imx6q.c arch/arm/mach-imx/cpuidle-imx6sx.c arch/arm/mach-imx/suspend-imx6.S block/blk-core.c drivers/crypto/caam/caamalg.c drivers/crypto/mxs-dcp.c drivers/dma/imx-sdma.c drivers/gpu/drm/bridge/adv7511/adv7511_drv.c drivers/input/keyboard/imx_keypad.c drivers/input/keyboard/snvs_pwrkey.c drivers/mmc/host/sdhci.c drivers/net/can/flexcan.c drivers/net/ethernet/freescale/fec_main.c drivers/net/phy/phy_device.c drivers/net/wireless/ath/ath10k/pci.c drivers/tty/serial/imx.c drivers/usb/dwc3/gadget.c drivers/usb/host/xhci.c include/linux/blkdev.h include/linux/cpu.h include/linux/platform_data/dma-imx-sdma.h kernel/cpu.c net/wireless/util.c sound/soc/fsl/Kconfig sound/soc/fsl/fsl_esai.c sound/soc/fsl/fsl_sai.c sound/soc/fsl/imx-sgtl5000.c
Diffstat (limited to 'mm/mincore.c')
-rw-r--r--mm/mincore.c23
1 files changed, 22 insertions, 1 deletions
diff --git a/mm/mincore.c b/mm/mincore.c
index bfb866435478..3b6a883d0926 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -167,6 +167,22 @@ out:
return 0;
}
+static inline bool can_do_mincore(struct vm_area_struct *vma)
+{
+ if (vma_is_anonymous(vma))
+ return true;
+ if (!vma->vm_file)
+ return false;
+ /*
+ * Reveal pagecache information only for non-anonymous mappings that
+ * correspond to the files the calling process could (if tried) open
+ * for writing; otherwise we'd be including shared non-exclusive
+ * mappings, which opens a side channel.
+ */
+ return inode_owner_or_capable(file_inode(vma->vm_file)) ||
+ inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
+}
+
/*
* Do a chunk of "sys_mincore()". We've already checked
* all the arguments, we hold the mmap semaphore: we should
@@ -187,8 +203,13 @@ static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *v
vma = find_vma(current->mm, addr);
if (!vma || addr < vma->vm_start)
return -ENOMEM;
- mincore_walk.mm = vma->vm_mm;
end = min(vma->vm_end, addr + (pages << PAGE_SHIFT));
+ if (!can_do_mincore(vma)) {
+ unsigned long pages = DIV_ROUND_UP(end - addr, PAGE_SIZE);
+ memset(vec, 1, pages);
+ return pages;
+ }
+ mincore_walk.mm = vma->vm_mm;
err = walk_page_range(addr, end, &mincore_walk);
if (err < 0)
return err;