ext/sysvshm: do not trust $size when opening an existing segment - #22982
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ext/sysvshm: do not trust $size when opening an existing segment#22982devnexen wants to merge 1 commit into
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shm_attach() wrote the requested size into the header of a segment it did not create, so a foreign segment framed as larger than it is let shm_put_var() write past the mapping. Take the size from shmctl() IPC_STAT instead, and reject a segment too small to hold the header. Noticed while reviewing phpGH-22959.
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shm_attach() wrote the requested size into the header of a segment it did not create, so a foreign segment framed as larger than it is let shm_put_var() write past the mapping. Take the size from shmctl() IPC_STAT instead, and reject a segment too small to hold the header.
Noticed while reviewing GH-22959.