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Fixup the geliboot sector rounding code

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Replace all rounding with the round{up,down}2 macros
a missing set of braces caused the previous code to be incorrect

replace alloca() with malloc() because alloca() can return an allocation
that is actually invalid, causing boot to fail

Reviewed by:	emaste, ed
Thanks To:	peter
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D6213
This commit is contained in:
Allan Jude 2016-05-20 01:41:47 +00:00
parent 71957470d5
commit 02fd555670
2 changed files with 31 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
sys/boot/i386/libi386/biosdisk.c
View File

@ -749,21 +749,29 @@ bd_read(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest)
* sectors cannot be decrypted. Round the requested LBA down to
* nearest multiple of DEV_GELIBOOT_BSIZE bytes.
*/
alignlba = dblk &
~(daddr_t)((DEV_GELIBOOT_BSIZE / BIOSDISK_SECSIZE) - 1);
alignlba = rounddown2(dblk * BD(dev).bd_sectorsize,
DEV_GELIBOOT_BSIZE) / BD(dev).bd_sectorsize;
/*
* Round number of blocks to read up to nearest multiple of
* DEV_GELIBOOT_BSIZE
*/
alignblks = blks + (dblk - alignlba) +
((DEV_GELIBOOT_BSIZE / BIOSDISK_SECSIZE) - 1) &
~(int)((DEV_GELIBOOT_BSIZE / BIOSDISK_SECSIZE) - 1);
diff = (dblk - alignlba) * BIOSDISK_SECSIZE;
diff = (dblk - alignlba) * BD(dev).bd_sectorsize;
alignblks = roundup2(blks * BD(dev).bd_sectorsize + diff,
DEV_GELIBOOT_BSIZE) / BD(dev).bd_sectorsize;
/*
* Use a temporary buffer here because the buffer provided by
* the caller may be too small.
* If the read is rounded up to a larger size, use a temporary
* buffer here because the buffer provided by the caller may be
* too small.
*/
tmpbuf = alloca(alignblks * BIOSDISK_SECSIZE);
if (diff == 0) {
tmpbuf = dest;
} else {
tmpbuf = malloc(alignblks * BD(dev).bd_sectorsize);
if (tmpbuf == NULL) {
return (-1);
}
}
err = bd_io(dev, alignlba, alignblks, tmpbuf, 0);
if (err)
@ -779,12 +787,15 @@ bd_read(struct disk_devdesc *dev, daddr_t dblk, int blks, caddr_t dest)
/* GELI needs the offset relative to the partition start */
p_off = alignlba - dskp.start;
err = geli_read(&dskp, p_off * BIOSDISK_SECSIZE, tmpbuf,
alignblks * BIOSDISK_SECSIZE);
err = geli_read(&dskp, p_off * BD(dev).bd_sectorsize, tmpbuf,
alignblks * BD(dev).bd_sectorsize);
if (err)
return (err);
bcopy(tmpbuf + diff, dest, blks * BIOSDISK_SECSIZE);
if (tmpbuf != dest) {
bcopy(tmpbuf + diff, dest, blks * BD(dev).bd_sectorsize);
free(tmpbuf);
}
return (0);
}
#endif /* LOADER_GELI_SUPPORT */
@ -898,10 +909,10 @@ bios_read(void *vdev __unused, struct dsk *priv, off_t off, char *buf, size_t by
dev.d_partition = priv->part;
dev.d_offset = priv->start;
off = off / BIOSDISK_SECSIZE;
off = off / BD(&dev).bd_sectorsize;
/* GELI gives us the offset relative to the partition start */
off += dev.d_offset;
bytes = bytes / BIOSDISK_SECSIZE;
bytes = bytes / BD(&dev).bd_sectorsize;
return (bd_io(&dev, off, bytes, buf, 0));
}

11
sys/boot/i386/zfsboot/zfsboot.c
View File

@ -200,7 +200,7 @@ vdev_read(vdev_t *vdev, void *priv, off_t off, void *buf, size_t bytes)
{
char *p;
daddr_t lba, alignlba;
off_t alignoff, diff;
off_t diff;
unsigned int nb, alignnb;
struct dsk *dsk = (struct dsk *) priv;
@ -210,10 +210,11 @@ vdev_read(vdev_t *vdev, void *priv, off_t off, void *buf, size_t bytes)
p = buf;
lba = off / DEV_BSIZE;
lba += dsk->start;
/* Align reads to 4k else 4k sector GELIs will not decrypt. */
alignoff = off & ~ (off_t)(DEV_GELIBOOT_BSIZE - 1);
/* Round LBA down to nearest multiple of DEV_GELIBOOT_BSIZE bytes. */
alignlba = alignoff / DEV_BSIZE;
/*
* Align reads to 4k else 4k sector GELIs will not decrypt.
* Round LBA down to nearest multiple of DEV_GELIBOOT_BSIZE bytes.
*/
alignlba = rounddown2(off, DEV_GELIBOOT_BSIZE) / DEV_BSIZE;
/*
* The read must be aligned to DEV_GELIBOOT_BSIZE bytes relative to the
* start of the GELI partition, not the start of the actual disk.