[linux] fix segfault when eventpoll fdinfo is unavailable - #368
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process_id() pre-fills -1 sentinels for the oty == 0 case, but tfd_count is size_t, so -1 becomes SIZE_MAX and the `fi.tfd_count > 0` guard passes where the `!= -1` siblings skip. snp_eventpoll() then qsorts SIZE_MAX entries of a 32-entry array. Declare it int, matching tfds[], the snp_eventpoll() parameters and the eventfd_id/pid sentinels.
jiegec
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Aug 11, 2026
| #define EPOLL_MAX_TFDS 32 | ||
| int tfds[EPOLL_MAX_TFDS]; | ||
| size_t tfd_count; | ||
| int tfd_count; |
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I think ssize_t is better? Then the struct size is unchanged, so the ABI is compatible.
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I will try once I have a time 🫡
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tfd_countis declaredsize_t(dproc.c:97), butprocess_id()uses-1as its "no fdinfo" sentinel (dproc.c:1222). It becomesSIZE_MAX, so thefi.tfd_count > 0guard passes where the!= -1siblings skip, andsnp_eventpoll()qsortsSIZE_MAXentries of a 32-entry array:This hits any run with
OffType != OFFSET_FDINFOthat reports a process holding an epoll descriptor. Declaring itintmatchestfds[]and theeventfd_id/pidsentinels.