Messages in this thread | | | Subject | Re: [PATCH bpf-next v2] bpf: fix segmentation fault of test_progs | From | Daniel Borkmann <> | Date | Tue, 11 Aug 2020 15:19:59 +0200 |
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On 8/10/20 5:39 PM, Jianlin Lv wrote: > test_progs reports the segmentation fault as below > > $ sudo ./test_progs -t mmap --verbose > test_mmap:PASS:skel_open_and_load 0 nsec > ...... > test_mmap:PASS:adv_mmap1 0 nsec > test_mmap:PASS:adv_mmap2 0 nsec > test_mmap:PASS:adv_mmap3 0 nsec > test_mmap:PASS:adv_mmap4 0 nsec > Segmentation fault > > This issue was triggered because mmap() and munmap() used inconsistent > length parameters; mmap() creates a new mapping of 3*page_size, but the > length parameter set in the subsequent re-map and munmap() functions is > 4*page_size; this leads to the destruction of the process space. > > To fix this issue, first create 4 pages of anonymous mapping,then do all > the mmap() with MAP_FIXED. > > Another issue is that when unmap the second page fails, the length > parameter to delete tmp1 mappings should be 4*page_size. > > Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
Applied, thanks!
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