From 513f2b0bbd47015640723a10210c527839e8946a Mon Sep 17 00:00:00 2001 From: Carlo Marcelo Arenas Belón Date: Wed, 16 Oct 2019 12:10:23 +0000 Subject: grep: make PCRE2 aware of custom allocator MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 94da9193a6 (grep: add support for PCRE v2, 2017-06-01) didn't include a way to override the system allocator, and so it is incompatible with custom allocators (e.g. nedmalloc). This problem became obvious when we tried to plug a memory leak by `free()`ing a data structure allocated by PCRE2, triggering a segfault in Windows (where we use nedmalloc by default). PCRE2 requires the use of a general context to override the allocator and therefore, there is a lot more code needed than in PCRE1, including a couple of wrapper functions. Extend the grep API with a "destructor" that could be called to cleanup any objects that were created and used globally. Update `builtin/grep.c` to use that new API, but any other future users should make sure to have matching `grep_init()`/`grep_destroy()` calls if they are using the pattern matching functionality. Move some of the logic that was before done per thread (in the workers) into an earlier phase to avoid degrading performance, but as the use of PCRE2 with custom allocators is better understood it is expected more of its functions will be instructed to use the custom allocator as well as was done in the original code[1] this work was based on. [1] https://public-inbox.org/git/3397e6797f872aedd18c6d795f4976e1c579514b.1565005867.git.gitgitgadget@gmail.com/ Reported-by: Johannes Schindelin Signed-off-by: Carlo Marcelo Arenas Belón Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- grep.h | 1 + 1 file changed, 1 insertion(+) (limited to 'grep.h') diff --git a/grep.h b/grep.h index 1875880f37..526c2db9ef 100644 --- a/grep.h +++ b/grep.h @@ -189,6 +189,7 @@ struct grep_opt { void init_grep_defaults(struct repository *); int grep_config(const char *var, const char *value, void *); void grep_init(struct grep_opt *, struct repository *repo, const char *prefix); +void grep_destroy(void); void grep_commit_pattern_type(enum grep_pattern_type, struct grep_opt *opt); void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen, const char *origin, int no, enum grep_pat_token t); -- cgit v1.3 From 10da030ab757c38a01507bf18e2484698000b791 Mon Sep 17 00:00:00 2001 From: Carlo Marcelo Arenas Belón Date: Wed, 16 Oct 2019 12:10:24 +0000 Subject: grep: avoid leak of chartables in PCRE2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 94da9193a6 ("grep: add support for PCRE v2", 2017-06-01) introduced a small memory leak visible with valgrind in t7813. Complete the creation of a PCRE2 specific variable that was missing from the original change and free the generated table just like it is done for PCRE1. Signed-off-by: Carlo Marcelo Arenas Belón Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- grep.c | 7 ++++--- grep.h | 1 + 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'grep.h') diff --git a/grep.c b/grep.c index 296edbb56f..9556d13dc1 100644 --- a/grep.c +++ b/grep.c @@ -525,7 +525,6 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt PCRE2_UCHAR errbuf[256]; PCRE2_SIZE erroffset; int options = PCRE2_MULTILINE; - const uint8_t *character_tables = NULL; int jitret; int patinforet; size_t jitsizearg; @@ -539,9 +538,10 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt if (has_non_ascii(p->pattern)) { if (!pcre2_global_context) BUG("pcre2_global_context uninitialized"); - character_tables = pcre2_maketables(pcre2_global_context); + p->pcre2_tables = pcre2_maketables(pcre2_global_context); p->pcre2_compile_context = pcre2_compile_context_create(NULL); - pcre2_set_character_tables(p->pcre2_compile_context, character_tables); + pcre2_set_character_tables(p->pcre2_compile_context, + p->pcre2_tables); } options |= PCRE2_CASELESS; } @@ -645,6 +645,7 @@ static void free_pcre2_pattern(struct grep_pat *p) pcre2_match_data_free(p->pcre2_match_data); pcre2_jit_stack_free(p->pcre2_jit_stack); pcre2_match_context_free(p->pcre2_match_context); + free((void *)p->pcre2_tables); } #else /* !USE_LIBPCRE2 */ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt) diff --git a/grep.h b/grep.h index 526c2db9ef..533165c21a 100644 --- a/grep.h +++ b/grep.h @@ -96,6 +96,7 @@ struct grep_pat { pcre2_compile_context *pcre2_compile_context; pcre2_match_context *pcre2_match_context; pcre2_jit_stack *pcre2_jit_stack; + const uint8_t *pcre2_tables; uint32_t pcre2_jit_on; kwset_t kws; unsigned fixed:1; -- cgit v1.3