diff options
| author | Kees Cook <keescook@chromium.org> | 2018-04-29 08:00:53 -0700 |
|---|---|---|
| committer | Boris Brezillon <boris.brezillon@bootlin.com> | 2018-04-30 16:11:16 +0200 |
| commit | 27ab41e2c183e960a045c8f3b87b2341a5f10f19 (patch) | |
| tree | 0168e650060ee93e20af3692c9ddd98fbab0651d | |
| parent | 7cc9aa669a5119a8d70b22c57779d1decd4d0d62 (diff) | |
mtd: nftl: Remove VLA usage
On the quest to remove all stack VLAs from the kernel[1] this changes
the check_free_sectors() routine to use a kmalloc()ed buffer instead
of a large VLA stack buffer.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
| -rw-r--r-- | drivers/mtd/inftlmount.c | 23 | ||||
| -rw-r--r-- | drivers/mtd/nftlmount.c | 23 |
2 files changed, 32 insertions, 14 deletions
diff --git a/drivers/mtd/inftlmount.c b/drivers/mtd/inftlmount.c index aab4f68bd36f..2d598412972d 100644 --- a/drivers/mtd/inftlmount.c +++ b/drivers/mtd/inftlmount.c @@ -334,28 +334,37 @@ static int memcmpb(void *a, int c, int n) static int check_free_sectors(struct INFTLrecord *inftl, unsigned int address, int len, int check_oob) { - u8 buf[SECTORSIZE + inftl->mbd.mtd->oobsize]; struct mtd_info *mtd = inftl->mbd.mtd; size_t retlen; - int i; + int i, ret; + u8 *buf; + + buf = kmalloc(SECTORSIZE + mtd->oobsize, GFP_KERNEL); + if (!buf) + return -1; + ret = -1; for (i = 0; i < len; i += SECTORSIZE) { if (mtd_read(mtd, address, SECTORSIZE, &retlen, buf)) - return -1; + goto out; if (memcmpb(buf, 0xff, SECTORSIZE) != 0) - return -1; + goto out; if (check_oob) { if(inftl_read_oob(mtd, address, mtd->oobsize, &retlen, &buf[SECTORSIZE]) < 0) - return -1; + goto out; if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0) - return -1; + goto out; } address += SECTORSIZE; } - return 0; + ret = 0; + +out: + kfree(buf); + return ret; } /* diff --git a/drivers/mtd/nftlmount.c b/drivers/mtd/nftlmount.c index a6fbfa4e5799..6281da3dadac 100644 --- a/drivers/mtd/nftlmount.c +++ b/drivers/mtd/nftlmount.c @@ -272,28 +272,37 @@ static int memcmpb(void *a, int c, int n) static int check_free_sectors(struct NFTLrecord *nftl, unsigned int address, int len, int check_oob) { - u8 buf[SECTORSIZE + nftl->mbd.mtd->oobsize]; struct mtd_info *mtd = nftl->mbd.mtd; size_t retlen; - int i; + int i, ret; + u8 *buf; + + buf = kmalloc(SECTORSIZE + mtd->oobsize, GFP_KERNEL); + if (!buf) + return -1; + ret = -1; for (i = 0; i < len; i += SECTORSIZE) { if (mtd_read(mtd, address, SECTORSIZE, &retlen, buf)) - return -1; + goto out; if (memcmpb(buf, 0xff, SECTORSIZE) != 0) - return -1; + goto out; if (check_oob) { if(nftl_read_oob(mtd, address, mtd->oobsize, &retlen, &buf[SECTORSIZE]) < 0) - return -1; + goto out; if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0) - return -1; + goto out; } address += SECTORSIZE; } - return 0; + ret = 0; + +out: + kfree(buf); + return ret; } /* NFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase Unit and |