Messages in this thread | | | Date | Tue, 18 Oct 2022 15:33:25 +0700 | Subject | Re: BISECT result: 6.0.0-RC kernels trigger Firefox snap bug with 6.0.0-rc3 through 6.0.0-rc7 | From | Bagas Sanjaya <> |
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On 10/18/22 14:23, Bagas Sanjaya wrote: > On 10/18/22 09:15, Jintao Yin wrote: >> Hi Phillip, >> There is a logical bug in commit 8fc78b6fe24c36b151ac98d7546591ed92083d4f >> which is parent commit of commit b09a7a036d2035b14636cd4c4c69518d73770f65. >> >> In function squashfs_readahead(...), >> file_end is initialized with i_size_read(inode) >> msblk->block_log, >> which means the last block index of the file. >> But later in the logic to check if the page is last one or not the >> code is >> if (pages[nr_pages - 1]->index == file_end && bytes) { >> ... >> } >> , use file_end as the last page index of file but actually is the last >> block index, so for the common setup of page and block size, the first >> comparison is true only when pages[nr_pages - 1]->index is 0. >> Otherwise, the trailing bytes of last page won't be zeroed. >> >> Maybe it's the real cause of the snap bug in some way. >> > > Hi Jintao, thanks for explaining the real culprit. However, I'd like to > see the fixup patch from you so that we can test. >
Sorry for inconvenience. Hsin-Yi Wang have already submitted the candidate fix at [1]. Thanks anyway.
[1]: https://lore.kernel.org/lkml/CAJMQK-hgQEkhgpO9VFOCgn-cKtVsr7Hb_58pAYiGoDi5SzGZtA@mail.gmail.com/
-- An old man doll... just what I always wanted! - Clara
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