From mboxrd@z Thu Jan 1 00:00:00 1970 From: AKASHI Takahiro Date: Wed, 27 Nov 2019 11:26:07 +0900 Subject: [U-Boot] [PATCH v3 1/6] fat: write: fix broken write to fragmented files In-Reply-To: <20191126165729.GA15966@bill-the-cat> References: <20191126081512.5138-1-m.szyprowski@samsung.com> <20191126081512.5138-2-m.szyprowski@samsung.com> <20191126165729.GA15966@bill-the-cat> Message-ID: <20191127022606.GK22427@linaro.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Thank you for the heads-up. On Tue, Nov 26, 2019 at 11:57:29AM -0500, Tom Rini wrote: > On Tue, Nov 26, 2019 at 09:15:07AM +0100, Marek Szyprowski wrote: > > > The code for handing file overwrite incorrectly assumed that the file on > > disk is always contiguous. This resulted in corrupting disk structure > > every time when write to existing fragmented file happened. Fix this > > by adding proper check for cluster discontinuity and adjust chunk size > > on each partial write. > > > > Signed-off-by: Marek Szyprowski > > Reviewed-by: Oleksandr Suvorov > > Reviewed-by: Lukasz Majewski > > --- > > fs/fat/fat_write.c | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c > > index 729cf39630..6cfa5b4565 100644 > > --- a/fs/fat/fat_write.c > > +++ b/fs/fat/fat_write.c > > @@ -794,6 +794,8 @@ set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, > > > > newclust = get_fatent(mydata, endclust); > > > > + if ((newclust - 1) != endclust) "newclust != (endclust + 1)" would be more intuitive? But it's just my preference. > > + break; > > if (IS_LAST_CLUST(newclust, mydata->fatsize)) > > break; > > if (CHECK_CLUST(newclust, mydata->fatsize)) { > > @@ -811,7 +813,7 @@ set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, > > offset = 0; > > else > > offset = pos - cur_pos; > > - wsize = min(cur_pos + actsize, filesize) - pos; > > + wsize = min_t(unsigned long long, actsize, filesize - cur_pos); This hunk is not directly related to the issue, is it? > > if (get_set_cluster(mydata, curclust, offset, > > buffer, wsize, &actsize)) { > > printf("Error get-and-setting cluster\n"); > > @@ -824,8 +826,6 @@ set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, > > if (filesize <= cur_pos) > > break; > > > > - /* CHECK: newclust = get_fatent(mydata, endclust); */ > > - > > if (IS_LAST_CLUST(newclust, mydata->fatsize)) > > /* no more clusters */ > > break; > > Adding in Heinrich and Akashi-san for more review on this, thanks! Otherwise, it looks good. Reviewed-by: AKASHI Takahiro > -- > Tom