fbc60d4 (Grow the JIT stack if it becomes exhausted, 2015-02-10), add support to grep for recovering from a JIT stack exhaustion problem, by creating and using increasingly larger stacks.
The underlying problem might seem to have been generated by a PCRE bug that is no longer reproducible, and the code could be simplified to do a single iteration instead with a theoretical maximum of almost INT_MAX, but that could be a regression, so instead make sure that the maximum size requested will always be valid, by avoiding a PCRE internal int overflow that will then be translated into an UINT_MAX like value by sljit. Alternatively, a smaller maximum could be selected as it has been documented[1] that more than 1MB would be unrealistic. [1] https://www.pcre.org/original/doc/html/pcrejit.html#SEC8 Signed-off-by: Carlo Marcelo Arenas Belón <care...@gmail.com> --- src/pcresearch.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/src/pcresearch.c b/src/pcresearch.c index 3bdaee9..c4fb09b 100644 --- a/src/pcresearch.c +++ b/src/pcresearch.c @@ -77,6 +77,10 @@ jit_exec (struct pcre_comp *pc, char const *subject, int search_bytes, { int old_size = pc->jit_stack_size; int new_size = pc->jit_stack_size = old_size * 2; + + /* PCRE will round up 8K bytes, so avoid overflow in maximum */ + if (INT_MAX - new_size < 8192) + new_size = INT_MAX - 8192; if (pc->jit_stack) pcre_jit_stack_free (pc->jit_stack); pc->jit_stack = pcre_jit_stack_alloc (old_size, new_size); -- 2.34.0.rc1.349.g8f33748433
