friendly ping... On 2022/12/9 11:37, lihaoxiang (F) wrote: > friendly ping... > > On 2022/11/29 15:02, lihaoxiang (F) wrote: >> In our knowledge, ext2fs_mmp_stop use to process the rest of work >> when mmp will finish. Critically, it must check if the mmp block is >> not changed. But there exist an error in comparing the mmp and mmp_cmp. >> >> Look to ext2fs_mmp_read, the assignment of mmp_cmp retrieve from the >> superblock of disk and it copy to mmp_buf if mmp_buf is not none >> and not equal to mmp_cmp in the meanwhile. However, ext2fs_mmp_stop >> pass the no NULL pointer fs->mmp_buf which has possed the mmp info to >> ext2fs_mmp_read. Consequently, ext2fs_mmp_read override fs->mmp_buf >> by fs->mmp_cmp so that loss the meaning of comparing themselves >> after that and worse yet, couldn't judge whether the struct of mmp >> has changed. >> >> In fact, we only need to modify the parameter to NULL pointer for >> solving this problem. >> >> Signed-off-by: lihaoxiang <lihaoxiang9@xxxxxxxxxx> >> --- >> lib/ext2fs/mmp.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/lib/ext2fs/mmp.c b/lib/ext2fs/mmp.c >> index 7970aac2..14289706 100644 >> --- a/lib/ext2fs/mmp.c >> +++ b/lib/ext2fs/mmp.c >> @@ -407,7 +407,7 @@ errcode_t ext2fs_mmp_stop(ext2_filsys fs) >> (fs->mmp_buf == NULL) || (fs->mmp_cmp == NULL)) >> goto mmp_error; >> >> - retval = ext2fs_mmp_read(fs, fs->super->s_mmp_block, fs->mmp_buf); >> + retval = ext2fs_mmp_read(fs, fs->super->s_mmp_block, NULL); >> if (retval) >> goto mmp_error; >>
