* [PATCH] nftl: fix offset alignments [not found] <605152405.3397101250633087167.JavaMail.root@zimbra3-e1.priv.proxad.net> @ 2009-08-18 22:06 ` dimitri.gorokhovik 2009-08-19 23:34 ` Andrew Morton 0 siblings, 1 reply; 3+ messages in thread From: dimitri.gorokhovik @ 2009-08-18 22:06 UTC (permalink / raw) To: David Woodhouse, David Woodhouse, Tim Gardner, Scott James Remnant, Julia Lawall, David Brownell Cc: linux-mtd, linux-kernel Arithmetic conversion in the mask computation makes the upper word of the second argument passed down to mtd->read_oob(), be always 0 (assuming 'offs' being a 64-bit signed long long type, and 'mtd->writesize' being a 32-bit unsigned int type). This patch applies over the other one adding masking in nftl_write, "nftl: write support is broken". Signed-off-by: <dimitri.gorokhovik@free.fr> --- diff --git a/drivers/mtd/nftlcore.c b/drivers/mtd/nftlcore.c index 665d3eb..d2fd066 100644 --- a/drivers/mtd/nftlcore.c +++ b/drivers/mtd/nftlcore.c @@ -135,16 +135,17 @@ static void nftl_remove_dev(struct mtd_blktrans_dev *dev) int nftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf) { + typeof(offs) mask = mtd->writesize - 1; struct mtd_oob_ops ops; int res; ops.mode = MTD_OOB_PLACE; - ops.ooboffs = offs & (mtd->writesize - 1); + ops.ooboffs = offs & mask; ops.ooblen = len; ops.oobbuf = buf; ops.datbuf = NULL; - res = mtd->read_oob(mtd, offs & ~(mtd->writesize - 1), &ops); + res = mtd->read_oob(mtd, offs & ~mask, &ops); *retlen = ops.oobretlen; return res; } @@ -155,16 +156,17 @@ int nftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, int nftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf) { + typeof(offs) mask = mtd->writesize - 1; struct mtd_oob_ops ops; int res; ops.mode = MTD_OOB_PLACE; - ops.ooboffs = offs & (mtd->writesize - 1); + ops.ooboffs = offs & mask; ops.ooblen = len; ops.oobbuf = buf; ops.datbuf = NULL; - res = mtd->write_oob(mtd, offs & ~(mtd->writesize - 1), &ops); + res = mtd->write_oob(mtd, offs & ~mask, &ops); *retlen = ops.oobretlen; return res; } @@ -177,17 +179,18 @@ int nftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len, static int nftl_write(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf, uint8_t *oob) { + typeof(offs) mask = mtd->writesize - 1; struct mtd_oob_ops ops; int res; ops.mode = MTD_OOB_PLACE; - ops.ooboffs = offs & (mtd->writesize - 1); + ops.ooboffs = offs & mask; ops.ooblen = mtd->oobsize; ops.oobbuf = oob; ops.datbuf = buf; ops.len = len; - res = mtd->write_oob(mtd, offs & ~(mtd->writesize - 1), &ops); + res = mtd->write_oob(mtd, offs & ~mask, &ops); *retlen = ops.retlen; return res; } ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] nftl: fix offset alignments 2009-08-18 22:06 ` [PATCH] nftl: fix offset alignments dimitri.gorokhovik @ 2009-08-19 23:34 ` Andrew Morton 2009-08-20 21:13 ` dimitri.gorokhovik 0 siblings, 1 reply; 3+ messages in thread From: Andrew Morton @ 2009-08-19 23:34 UTC (permalink / raw) To: dimitri.gorokhovik Cc: Scott James Remnant, David Brownell, David Woodhouse, linux-kernel, Julia Lawall, linux-mtd, Tim Gardner, David Woodhouse On Wed, 19 Aug 2009 00:06:28 +0200 (CEST) dimitri.gorokhovik@free.fr wrote: > Arithmetic conversion in the mask computation makes the upper word > of the second argument passed down to mtd->read_oob(), be always 0 > (assuming 'offs' being a 64-bit signed long long type, and > 'mtd->writesize' being a 32-bit unsigned int type). > > This patch applies over the other one adding masking in nftl_write, > "nftl: write support is broken". > > Signed-off-by: <dimitri.gorokhovik@free.fr> > --- > > diff --git a/drivers/mtd/nftlcore.c b/drivers/mtd/nftlcore.c > index 665d3eb..d2fd066 100644 > --- a/drivers/mtd/nftlcore.c > +++ b/drivers/mtd/nftlcore.c > @@ -135,16 +135,17 @@ static void nftl_remove_dev(struct mtd_blktrans_dev *dev) > int nftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, > size_t *retlen, uint8_t *buf) > { > + typeof(offs) mask = mtd->writesize - 1; I see no reason to use typeof here. Plain old loff_t mask = mtd->writesize - 1; would be more conventional. > struct mtd_oob_ops ops; > int res; > > ops.mode = MTD_OOB_PLACE; > - ops.ooboffs = offs & (mtd->writesize - 1); > + ops.ooboffs = offs & mask; > ops.ooblen = len; > ops.oobbuf = buf; > ops.datbuf = NULL; > > - res = mtd->read_oob(mtd, offs & ~(mtd->writesize - 1), &ops); > + res = mtd->read_oob(mtd, offs & ~mask, &ops); yup. ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] nftl: fix offset alignments 2009-08-19 23:34 ` Andrew Morton @ 2009-08-20 21:13 ` dimitri.gorokhovik 0 siblings, 0 replies; 3+ messages in thread From: dimitri.gorokhovik @ 2009-08-20 21:13 UTC (permalink / raw) To: Andrew Morton Cc: Scott James Remnant, David Brownell, David Woodhouse, linux-kernel, Julia Lawall, linux-mtd, Tim Gardner, David Woodhouse "Andrew Morton" <akpm@linux-foundation.org> a écrit : > On Wed, 19 Aug 2009 00:06:28 +0200 (CEST) dimitri.gorokhovik@free.fr > wrote: > ... > > + typeof(offs) mask = mtd->writesize - 1; > > I see no reason to use typeof here. Plain old > > loff_t mask = mtd->writesize - 1; > > would be more conventional. I use typeoff in this way to guard masking code against absent-minded modifications. Attached is a corrected version as suggested. Maybe Julia can come up with a clever rule for detecting unusual masking operations automatically :-) ? --- From: Dimitri Gorokhovik <dimitri.gorokhovik@free.fr> Subject: nftl: fix offset alignments Arithmetic conversion in the mask computation makes the upper word of the second argument passed down to mtd->read_oob(), be always 0 (assuming 'offs' being a 64-bit signed long long type, and 'mtd->writesize' being a 32-bit unsigned int type). This patch applies over the other one adding masking in nftl_write, "nftl: write support is broken". Signed-off-by: Dimitri Gorokhovik <dimitri.gorokhovik@free.fr> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Tim Gardner <tim.gardner@canonical.com> Cc: Scott James Remnant <scott@canonical.com> --- drivers/mtd/nftlcore.c | 15 +++++++++------ 1 files changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/mtd/nftlcore.c b/drivers/mtd/nftlcore.c index 665d3eb..1002e18 100644 --- a/drivers/mtd/nftlcore.c +++ b/drivers/mtd/nftlcore.c @@ -135,16 +135,17 @@ static void nftl_remove_dev(struct mtd_blktrans_dev *dev) int nftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf) { + loff_t mask = mtd->writesize - 1; struct mtd_oob_ops ops; int res; ops.mode = MTD_OOB_PLACE; - ops.ooboffs = offs & (mtd->writesize - 1); + ops.ooboffs = offs & mask; ops.ooblen = len; ops.oobbuf = buf; ops.datbuf = NULL; - res = mtd->read_oob(mtd, offs & ~(mtd->writesize - 1), &ops); + res = mtd->read_oob(mtd, offs & ~mask, &ops); *retlen = ops.oobretlen; return res; } @@ -155,16 +156,17 @@ int nftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, int nftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf) { + loff_t mask = mtd->writesize - 1; struct mtd_oob_ops ops; int res; ops.mode = MTD_OOB_PLACE; - ops.ooboffs = offs & (mtd->writesize - 1); + ops.ooboffs = offs & mask; ops.ooblen = len; ops.oobbuf = buf; ops.datbuf = NULL; - res = mtd->write_oob(mtd, offs & ~(mtd->writesize - 1), &ops); + res = mtd->write_oob(mtd, offs & ~mask, &ops); *retlen = ops.oobretlen; return res; } @@ -177,17 +179,18 @@ int nftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len, static int nftl_write(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf, uint8_t *oob) { + loff_t mask = mtd->writesize - 1; struct mtd_oob_ops ops; int res; ops.mode = MTD_OOB_PLACE; - ops.ooboffs = offs & (mtd->writesize - 1); + ops.ooboffs = offs & mask; ops.ooblen = mtd->oobsize; ops.oobbuf = oob; ops.datbuf = buf; ops.len = len; - res = mtd->write_oob(mtd, offs & ~(mtd->writesize - 1), &ops); + res = mtd->write_oob(mtd, offs & ~mask, &ops); *retlen = ops.retlen; return res; } -- 1.6.3.3 ^ permalink raw reply related [flat|nested] 3+ messages in thread
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2009-08-18 22:06 ` [PATCH] nftl: fix offset alignments dimitri.gorokhovik
2009-08-19 23:34 ` Andrew Morton
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