commit-graph: close descriptors after mmap
We don't ever refer to the descriptor after mmap-ing it. And keeping it open means we can run out of descriptors in degenerate cases (e.g., thousands of split chain files). Let's close it as soon as possible. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King committed
Apr 23, 2020 at 15:41 UTC
c8828530b7797f5ab584c84dc2b86d3c14b39c8d
3 files changed
+8
-17
commit-graph.c
+5
-10
@@ -69,7 +69,6 @@ static uint8_t oid_version(void)
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static struct commit_graph *alloc_commit_graph(void)
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{
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struct commit_graph *g = xcalloc(1, sizeof(*g));
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- g->graph_fd = -1;
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return g;
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}
@@ -123,14 +122,13 @@ struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st,
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return NULL;
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}
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graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
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- ret = parse_commit_graph(graph_map, fd, graph_size);
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+ close(fd);
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+ ret = parse_commit_graph(graph_map, graph_size);
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if (ret)
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ret->odb = odb;
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- else {
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+ else
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munmap(graph_map, graph_size);
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- close(fd);
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- }
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return ret;
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}
@@ -165,8 +163,7 @@ static int verify_commit_graph_lite(struct commit_graph *g)
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return 0;
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}
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-struct commit_graph *parse_commit_graph(void *graph_map, int fd,
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- size_t graph_size)
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+struct commit_graph *parse_commit_graph(void *graph_map, size_t graph_size)
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{
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const unsigned char *data, *chunk_lookup;
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uint32_t i;
@@ -209,7 +206,6 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
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graph->hash_len = the_hash_algo->rawsz;
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graph->num_chunks = *(unsigned char*)(data + 6);
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- graph->graph_fd = fd;
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graph->data = graph_map;
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graph->data_len = graph_size;
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@@ -2129,10 +2125,9 @@ void free_commit_graph(struct commit_graph *g)
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{
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if (!g)
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return;
2132
- if (g->graph_fd >= 0) {
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+ if (g->data) {
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munmap((void *)g->data, g->data_len);
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g->data = NULL;
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- close(g->graph_fd);
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}
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free(g->filename);
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free(g);
commit-graph.h
+1
-4
@@ -40,8 +40,6 @@ struct tree *get_commit_tree_in_graph(struct repository *r,
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const struct commit *c);
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struct commit_graph {
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- int graph_fd;
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-
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const unsigned char *data;
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size_t data_len;
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@@ -66,8 +64,7 @@ struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st,
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struct object_directory *odb);
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struct commit_graph *read_commit_graph_one(struct repository *r,
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struct object_directory *odb);
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-struct commit_graph *parse_commit_graph(void *graph_map, int fd,
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- size_t graph_size);
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+struct commit_graph *parse_commit_graph(void *graph_map, size_t graph_size);
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/*
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* Return 1 if and only if the repository has a commit-graph
fuzz-commit-graph.c
+2
-3
@@ -1,8 +1,7 @@
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#include "commit-graph.h"
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#include "repository.h"
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-struct commit_graph *parse_commit_graph(void *graph_map, int fd,
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- size_t graph_size);
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+struct commit_graph *parse_commit_graph(void *graph_map, size_t graph_size);
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int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
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@@ -11,7 +10,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
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struct commit_graph *g;
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initialize_the_repository();
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- g = parse_commit_graph((void *)data, -1, size);
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+ g = parse_commit_graph((void *)data, size);
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repo_clear(the_repository);
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free(g);
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