Messages in this thread | | | Subject | Re: [PATCH] fs: btrfs: Fix a possible null-pointer dereference in insert_inline_extent() | From | Jia-Ju Bai <> | Date | Wed, 24 Jul 2019 10:33:51 +0800 |
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On 2019/7/24 10:21, Qu Wenruo wrote: > > On 2019/7/24 上午10:11, Jia-Ju Bai wrote: >> In insert_inline_extent(), there is an if statement on line 181 to check >> whether compressed_pages is NULL: >> if (compressed_size && compressed_pages) >> >> When compressed_pages is NULL, compressed_pages is used on line 215: >> cpage = compressed_pages[i]; >> >> Thus, a possible null-pointer dereference may occur. >> >> To fix this possible bug, compressed_pages is checked on line 214. > This can only be hit with compressed_size > 0 and compressed_pages != NULL. > > It would be better to have an extra ASSERT() to warn developers about > the impossible case.
Thanks for the reply :) So I should add ASSERT(compressed_size > 0 & compressed_pages) at the beginning of the function, and remove "if (compressed_size && compressed_pages)"?
Best wishes, Jia-Ju Bai
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