| Message ID | 20191126081512.5138-2-m.szyprowski@samsung.com |
|---|---|
| State | Superseded |
| Delegated to: | Matthias Brugger |
| Headers | show |
| Series | Raspberry Pi4: add support for DFU over USB | expand |
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 <m.szyprowski@samsung.com> > Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com> > Reviewed-by: Lukasz Majewski <lukma@denx.de> > --- > 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) > + 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; Adding in Heinrich and Akashi-san for more review on this, thanks!
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 <m.szyprowski@samsung.com> > > Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com> > > Reviewed-by: Lukasz Majewski <lukma@denx.de> > > --- > > 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 <takahiro.akashi@linaro.org> > -- > Tom
Hi, On 27.11.2019 03:26, AKASHI Takahiro wrote: > 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 <m.szyprowski@samsung.com> >>> Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com> >>> Reviewed-by: Lukasz Majewski <lukma@denx.de> >>> --- >>> 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. Indeed. >>> + 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? It is partially related. I remember that it was not calculated correctly for the fragmented files and then discovered that there was one more case in which the current formula failed. >>> 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 <takahiro.akashi@linaro.org> Best regards
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) + 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;