From: Dan Rosenberg Date: Mon, 6 Sep 2010 22:24:57 +0000 (-0400) Subject: xfs: prevent reading uninitialized stack memory X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a122eb2fdfd78b58c6dd992d6f4b1aaef667eef9;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git xfs: prevent reading uninitialized stack memory The XFS_IOC_FSGETXATTR ioctl allows unprivileged users to read 12 bytes of uninitialized stack memory, because the fsxattr struct declared on the stack in xfs_ioc_fsgetxattr() does not alter (or zero) the 12-byte fsx_pad member before copying it back to the user. This patch takes care of it. Signed-off-by: Dan Rosenberg Reviewed-by: Eric Sandeen Signed-off-by: Alex Elder --- diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c index 4fec427b83e..3b9e626f7cd 100644 --- a/fs/xfs/linux-2.6/xfs_ioctl.c +++ b/fs/xfs/linux-2.6/xfs_ioctl.c @@ -785,6 +785,8 @@ xfs_ioc_fsgetxattr( { struct fsxattr fa; + memset(&fa, 0, sizeof(struct fsxattr)); + xfs_ilock(ip, XFS_ILOCK_SHARED); fa.fsx_xflags = xfs_ip2xflags(ip); fa.fsx_extsize = ip->i_d.di_extsize << ip->i_mount->m_sb.sb_blocklog;