On 7 June 2015 at 22:05, Sergei Antonov <saproj@xxxxxxxxx> wrote: > On 10 April 2015 at 18:48, Viacheslav Dubeyko <slava@xxxxxxxxxxx> wrote: >> On Fri, 2015-04-10 at 11:02 +0200, Sergei Antonov wrote: >>> Function hfsplus_submit_bio() did not work when the passed buffer spanned >>> over more than one page. That was because bio_alloc() is passed 1 as a number >>> of vectors but more than one vector were added inside the 'while' loop. >>> It periodically caused a mount error when the volume header could not be read. >>> >>> This patch modifies the code so that only one vector is used. It works for >>> multiple pages too. Also adds a return code check after bio_alloc(). >> >> I think that it really makes sense to describe the issue's reproducing >> way. It will be really precious for understanding of symptoms and >> reasons of the issue. >> >> Could you add more detailed description? >> >> Then, I will have opportunity to test your patch. > > Well, the description says it all. To put it bluntly, when this line > from wrapper.c > sbi->s_vhdr_buf = kmalloc(hfsplus_min_io_size(sb), GFP_KERNEL); > assigns s_vhdr_buf a value satisfying condition (PAGE_SIZE - (value & > PAGE_SIZE) < 512) then this call (also from wrapper.c) returns an I'm sorry, the right condition is (PAGE_SIZE - (value & (PAGE_SIZE - 1)) < 512). > error: > error = hfsplus_submit_bio(sb, part_start + HFSPLUS_VOLHEAD_SECTOR, > sbi->s_vhdr_buf, (void **)&sbi->s_vhdr, > READ); > > To give a specific example, sbi->s_vhdr_buf equal to > 0xffff8804085acec0 spans two pages and hfsplus_submit_bio() can not > read into such a buffer, returns an error, mount operation fails. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
