From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Majewski Date: Mon, 16 Sep 2019 23:38:01 +0200 Subject: [U-Boot] [PATCH 1/3] fat: write: fix broken write to fragmented files In-Reply-To: <20190916122417.27520-2-m.szyprowski@samsung.com> References: <20190916122417.27520-1-m.szyprowski@samsung.com> <20190916122417.27520-2-m.szyprowski@samsung.com> Message-ID: <20190916233801.656c39aa@jawa> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Marek, > 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 > --- > 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 729cf39630d..6cfa5b45652 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) > + 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); 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; Reviewed-by: Lukasz Majewski Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma at denx.de -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 488 bytes Desc: OpenPGP digital signature URL: