* [PATCH] commit-graph: avoid leaking topo_levels slab in write_commit_graph()
@ 2021-02-19 20:13 Andrzej Hunt via GitGitGadget
2021-02-20 3:36 ` Junio C Hamano
0 siblings, 1 reply; 5+ messages in thread
From: Andrzej Hunt via GitGitGadget @ 2021-02-19 20:13 UTC (permalink / raw)
To: git; +Cc: Andrzej Hunt, Andrzej Hunt
From: Andrzej Hunt <ajrhunt@google.com>
write_commit_graph initialises topo_levels using init_topo_level_slab(),
next it calls compute_topological_levels() which can cause the slab to
grow, we therefore need to clear the slab again using
clear_topo_level_slab() when we're done.
First introduced in 72a2bfcaf01860ce8dd6921490d903dc0ad59c89 - which
is currently only in master and not on maint.
LeakSanitizer output:
==1026==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x498ae9 in realloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xafbed8 in xrealloc /src/git/wrapper.c:126:8
#2 0x7966d1 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1
#3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1
#4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12
#5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2
#6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6
#7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11
#8 0x4cddb1 in run_builtin /src/git/git.c:453:11
#9 0x4cabe2 in handle_builtin /src/git/git.c:704:3
#10 0x4cd084 in run_argv /src/git/git.c:771:4
#11 0x4ca424 in cmd_main /src/git/git.c:902:19
#12 0x707fb6 in main /src/git/common-main.c:52:11
#13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
Indirect leak of 524256 byte(s) in 1 object(s) allocated from:
#0 0x498942 in calloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0xafc088 in xcalloc /src/git/wrapper.c:140:8
#2 0x796870 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1
#3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1
#4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12
#5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2
#6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6
#7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11
#8 0x4cddb1 in run_builtin /src/git/git.c:453:11
#9 0x4cabe2 in handle_builtin /src/git/git.c:704:3
#10 0x4cd084 in run_argv /src/git/git.c:771:4
#11 0x4ca424 in cmd_main /src/git/git.c:902:19
#12 0x707fb6 in main /src/git/common-main.c:52:11
#13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
SUMMARY: AddressSanitizer: 524264 byte(s) leaked in 2 allocation(s).
Signed-off-by: Andrzej Hunt <ajrhunt@google.com>
---
commit-graph: avoid leaking topo_levels slab in write_commit_graph()
write_commit_graph initialises topo_levels using init_topo_level_slab(),
next it calls compute_topological_levels() which can cause the slab to
grow, we therefore need to clear the slab again using
clear_topo_level_slab() when we're done.
First introduced in 72a2bfcaf01860ce8dd6921490d903dc0ad59c89 - which is
currently only in master and not on maint.
LeakSanitizer output:
==1026==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 8 byte(s) in 1 object(s) allocated from: #0 0x498ae9 in
realloc
/src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 #1
0xafbed8 in xrealloc /src/git/wrapper.c:126:8 #2 0x7966d1 in
topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in
topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in
compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3
in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in
graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in
cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in
run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin
/src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11
0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main
/src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main
(/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
Indirect leak of 524256 byte(s) in 1 object(s) allocated from: #0
0x498942 in calloc
/src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3 #1
0xafc088 in xcalloc /src/git/wrapper.c:140:8 #2 0x796870 in
topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in
topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in
compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3
in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in
graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in
cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in
run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin
/src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11
0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main
/src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main
(/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
SUMMARY: AddressSanitizer: 524264 byte(s) leaked in 2 allocation(s).
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-881%2Fahunt%2Fcommit-graph-leak-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-881/ahunt/commit-graph-leak-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/881
commit-graph.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/commit-graph.c b/commit-graph.c
index ed31843fa522..9529ec552139 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -2471,6 +2471,7 @@ int write_commit_graph(struct object_directory *odb,
free(ctx->graph_name);
free(ctx->commits.list);
oid_array_clear(&ctx->oids);
+ clear_topo_level_slab(&topo_levels);
if (ctx->commit_graph_filenames_after) {
for (i = 0; i < ctx->num_commit_graphs_after; i++) {
base-commit: 2283e0e9af55689215afa39c03beb2315ce18e83
--
gitgitgadget
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH] commit-graph: avoid leaking topo_levels slab in write_commit_graph()
2021-02-19 20:13 [PATCH] commit-graph: avoid leaking topo_levels slab in write_commit_graph() Andrzej Hunt via GitGitGadget
@ 2021-02-20 3:36 ` Junio C Hamano
2021-02-22 14:15 ` Derrick Stolee
0 siblings, 1 reply; 5+ messages in thread
From: Junio C Hamano @ 2021-02-20 3:36 UTC (permalink / raw)
To: Andrzej Hunt via GitGitGadget, Derrick Stolee, Abhishek Kumar,
Taylor Blau
Cc: git, Andrzej Hunt, Andrzej Hunt
"Andrzej Hunt via GitGitGadget" <gitgitgadget@gmail.com> writes:
> From: Andrzej Hunt <ajrhunt@google.com>
>
> write_commit_graph initialises topo_levels using init_topo_level_slab(),
> next it calls compute_topological_levels() which can cause the slab to
> grow, we therefore need to clear the slab again using
> clear_topo_level_slab() when we're done.
>
> First introduced in 72a2bfcaf01860ce8dd6921490d903dc0ad59c89 - which
> is currently only in master and not on maint.
Thanks.
Forwarding to those who were involved in the said commit for
insights.
> LeakSanitizer output:
>
> ==1026==ERROR: LeakSanitizer: detected memory leaks
>
> Direct leak of 8 byte(s) in 1 object(s) allocated from:
> #0 0x498ae9 in realloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
> #1 0xafbed8 in xrealloc /src/git/wrapper.c:126:8
> #2 0x7966d1 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1
> #3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1
> #4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12
> #5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2
> #6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6
> #7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11
> #8 0x4cddb1 in run_builtin /src/git/git.c:453:11
> #9 0x4cabe2 in handle_builtin /src/git/git.c:704:3
> #10 0x4cd084 in run_argv /src/git/git.c:771:4
> #11 0x4ca424 in cmd_main /src/git/git.c:902:19
> #12 0x707fb6 in main /src/git/common-main.c:52:11
> #13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
>
> Indirect leak of 524256 byte(s) in 1 object(s) allocated from:
> #0 0x498942 in calloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
> #1 0xafc088 in xcalloc /src/git/wrapper.c:140:8
> #2 0x796870 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1
> #3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1
> #4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12
> #5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2
> #6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6
> #7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11
> #8 0x4cddb1 in run_builtin /src/git/git.c:453:11
> #9 0x4cabe2 in handle_builtin /src/git/git.c:704:3
> #10 0x4cd084 in run_argv /src/git/git.c:771:4
> #11 0x4ca424 in cmd_main /src/git/git.c:902:19
> #12 0x707fb6 in main /src/git/common-main.c:52:11
> #13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
>
> SUMMARY: AddressSanitizer: 524264 byte(s) leaked in 2 allocation(s).
>
> Signed-off-by: Andrzej Hunt <ajrhunt@google.com>
> ---
> commit-graph: avoid leaking topo_levels slab in write_commit_graph()
>
> write_commit_graph initialises topo_levels using init_topo_level_slab(),
> next it calls compute_topological_levels() which can cause the slab to
> grow, we therefore need to clear the slab again using
> clear_topo_level_slab() when we're done.
>
> First introduced in 72a2bfcaf01860ce8dd6921490d903dc0ad59c89 - which is
> currently only in master and not on maint.
>
> LeakSanitizer output:
>
> ==1026==ERROR: LeakSanitizer: detected memory leaks
>
> Direct leak of 8 byte(s) in 1 object(s) allocated from: #0 0x498ae9 in
> realloc
> /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 #1
> 0xafbed8 in xrealloc /src/git/wrapper.c:126:8 #2 0x7966d1 in
> topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in
> topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in
> compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3
> in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in
> graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in
> cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in
> run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin
> /src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11
> 0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main
> /src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main
> (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
>
> Indirect leak of 524256 byte(s) in 1 object(s) allocated from: #0
> 0x498942 in calloc
> /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3 #1
> 0xafc088 in xcalloc /src/git/wrapper.c:140:8 #2 0x796870 in
> topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in
> topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in
> compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3
> in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in
> graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in
> cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in
> run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin
> /src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11
> 0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main
> /src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main
> (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
>
> SUMMARY: AddressSanitizer: 524264 byte(s) leaked in 2 allocation(s).
>
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-881%2Fahunt%2Fcommit-graph-leak-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-881/ahunt/commit-graph-leak-v1
> Pull-Request: https://github.com/gitgitgadget/git/pull/881
>
> commit-graph.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/commit-graph.c b/commit-graph.c
> index ed31843fa522..9529ec552139 100644
> --- a/commit-graph.c
> +++ b/commit-graph.c
> @@ -2471,6 +2471,7 @@ int write_commit_graph(struct object_directory *odb,
> free(ctx->graph_name);
> free(ctx->commits.list);
> oid_array_clear(&ctx->oids);
> + clear_topo_level_slab(&topo_levels);
>
> if (ctx->commit_graph_filenames_after) {
> for (i = 0; i < ctx->num_commit_graphs_after; i++) {
>
> base-commit: 2283e0e9af55689215afa39c03beb2315ce18e83
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] commit-graph: avoid leaking topo_levels slab in write_commit_graph()
2021-02-20 3:36 ` Junio C Hamano
@ 2021-02-22 14:15 ` Derrick Stolee
2021-02-22 19:14 ` Andrzej Hunt
0 siblings, 1 reply; 5+ messages in thread
From: Derrick Stolee @ 2021-02-22 14:15 UTC (permalink / raw)
To: Junio C Hamano, Andrzej Hunt via GitGitGadget, Derrick Stolee,
Abhishek Kumar, Taylor Blau
Cc: git, Andrzej Hunt, Andrzej Hunt
On 2/19/2021 10:36 PM, Junio C Hamano wrote:
> "Andrzej Hunt via GitGitGadget" <gitgitgadget@gmail.com> writes:
>
>> From: Andrzej Hunt <ajrhunt@google.com>
>>
>> write_commit_graph initialises topo_levels using init_topo_level_slab(),
>> next it calls compute_topological_levels() which can cause the slab to
>> grow, we therefore need to clear the slab again using
>> clear_topo_level_slab() when we're done.
>>
>> First introduced in 72a2bfcaf01860ce8dd6921490d903dc0ad59c89 - which
>> is currently only in master and not on maint.
>
> Thanks.
>
> Forwarding to those who were involved in the said commit for
> insights.
>> index ed31843fa522..9529ec552139 100644
>> --- a/commit-graph.c
>> +++ b/commit-graph.c
>> @@ -2471,6 +2471,7 @@ int write_commit_graph(struct object_directory *odb,
>> free(ctx->graph_name);
>> free(ctx->commits.list);
>> oid_array_clear(&ctx->oids);
>> + clear_topo_level_slab(&topo_levels);
This change looks like a sane change to me. It definitely fixes a leak.
The leak "wasn't hurting anybody" because write_commit_graph() is only
called at most once per process, and the process closes itself out
shortly after. Still, it's good to have good memory hygiene here.
Thanks,
-Stolee
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] commit-graph: avoid leaking topo_levels slab in write_commit_graph()
2021-02-22 14:15 ` Derrick Stolee
@ 2021-02-22 19:14 ` Andrzej Hunt
0 siblings, 0 replies; 5+ messages in thread
From: Andrzej Hunt @ 2021-02-22 19:14 UTC (permalink / raw)
To: Derrick Stolee, Junio C Hamano, Andrzej Hunt via GitGitGadget,
Derrick Stolee, Abhishek Kumar, Taylor Blau
Cc: git, Andrzej Hunt
On 22/02/2021 15:15, Derrick Stolee wrote:
> This change looks like a sane change to me. It definitely fixes a leak.
> The leak "wasn't hurting anybody" because write_commit_graph() is only
> called at most once per process, and the process closes itself out
> shortly after. Still, it's good to have good memory hygiene here.
Good to know - thank you! As I become more familiar with git, I'm
beginning to realise that most leaks are unlikely to be much importance
(even though I personally err on the side of fixing any and all issues).
One thing I forgot to mention: in this specific case the leak was
causing a build failure when trying to build git's fuzzers within
oss-fuzz locally*. Specifically the following command would fail (see
also fuzz failure reproduction instructions which describe the setup [1]).
$ python infra/helper.py build_fuzzers --sanitizer address git
As far as I can tell the issue is that: a copy of git built with ASAN is
used to produce the fuzzing corpus as part of the git-specific build
script [2] - the leak warning causes the script to fail. (It's possible
to argue that the build script should disable ASAN's leak checking when
running git, via detect_leaks=0 to reduce the risk of such breakage - I
may try to suggest such a change to oss-fuzz.)
ATB,
Andrzej
* Given that oss-fuzz is building via docker, I would intuitively
suspect that the same issue occurs in automation - I'm not sure how to
verify this myself.
[1]
https://google.github.io/oss-fuzz/advanced-topics/reproducing/#building-using-docker
[2]
https://github.com/google/oss-fuzz/blob/1b0115eefd70491376cf3cb6f88e49632c78ee18/projects/git/build.sh#L37
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] commit-graph: avoid leaking topo_levels slab in write_commit_graph()
@ 2021-02-25 6:26 Abhishek Kumar
0 siblings, 0 replies; 5+ messages in thread
From: Abhishek Kumar @ 2021-02-25 6:26 UTC (permalink / raw)
To: gitgitgadget; +Cc: ajrhunt, andrzej, git
"Andrzej Hunt via GitGitGadget" <gitgitgadget@gmail.com> writes:
> From: Andrzej Hunt <ajrhunt@google.com>
>
> write_commit_graph initialises topo_levels using init_topo_level_slab(),
> next it calls compute_topological_levels() which can cause the slab to
> grow, we therefore need to clear the slab again using
> clear_topo_level_slab() when we're done.
>
> First introduced in 72a2bfcaf01860ce8dd6921490d903dc0ad59c89 - which
> is currently only in master and not on maint.
>
Thanks for identifying and fixing this memory leak!
- Abhishek
> LeakSanitizer output:
> ==1026==ERROR: LeakSanitizer: detected memory leaks
> Direct leak of 8 byte(s) in 1 object(s) allocated from:
> #0 0x498ae9 in realloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
> #1 0xafbed8 in xrealloc /src/git/wrapper.c:126:8
> #2 0x7966d1 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1
> #3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1
> #4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12
> #5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2
> #6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6
> #7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11
> #8 0x4cddb1 in run_builtin /src/git/git.c:453:11
> #9 0x4cabe2 in handle_builtin /src/git/git.c:704:3
> #10 0x4cd084 in run_argv /src/git/git.c:771:4
> #11 0x4ca424 in cmd_main /src/git/git.c:902:19
> #12 0x707fb6 in main /src/git/common-main.c:52:11
> #13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
> Indirect leak of 524256 byte(s) in 1 object(s) allocated from:
> #0 0x498942 in calloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
> #1 0xafc088 in xcalloc /src/git/wrapper.c:140:8
> #2 0x796870 in topo_level_slab_at_peek /src/git/commit-graph.c:71:1
> #3 0x7965e0 in topo_level_slab_at /src/git/commit-graph.c:71:1
> #4 0x78fbf5 in compute_topological_levels /src/git/commit-graph.c:1472:12
> #5 0x78c5c3 in write_commit_graph /src/git/commit-graph.c:2456:2
> #6 0x535c5f in graph_write /src/git/builtin/commit-graph.c:299:6
> #7 0x5350ca in cmd_commit_graph /src/git/builtin/commit-graph.c:337:11
> #8 0x4cddb1 in run_builtin /src/git/git.c:453:11
> #9 0x4cabe2 in handle_builtin /src/git/git.c:704:3
> #10 0x4cd084 in run_argv /src/git/git.c:771:4
> #11 0x4ca424 in cmd_main /src/git/git.c:902:19
> #12 0x707fb6 in main /src/git/common-main.c:52:11
> #13 0x7fee4249383f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
> SUMMARY: AddressSanitizer: 524264 byte(s) leaked in 2 allocation(s).
> Signed-off-by: Andrzej Hunt <ajrhunt@google.com>
> ---
> commit-graph: avoid leaking topo_levels slab in write_commit_graph()
>
> write_commit_graph initialises topo_levels using init_topo_level_slab(),
> next it calls compute_topological_levels() which can cause the slab to
> grow, we therefore need to clear the slab again using
> clear_topo_level_slab() when we're done.
>
> First introduced in 72a2bfcaf01860ce8dd6921490d903dc0ad59c89 - which is
> currently only in master and not on maint.
>
> LeakSanitizer output:
>
> ==1026==ERROR: LeakSanitizer: detected memory leaks
>
> Direct leak of 8 byte(s) in 1 object(s) allocated from: #0 0x498ae9 in
> realloc
> /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 #1
> 0xafbed8 in xrealloc /src/git/wrapper.c:126:8 #2 0x7966d1 in
> topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in
> topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in
> compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3
> in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in
> graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in
> cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in
> run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin
> /src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11
> 0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main
> /src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main
> (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
>
> Indirect leak of 524256 byte(s) in 1 object(s) allocated from: #0
> 0x498942 in calloc
> /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3 #1
> 0xafc088 in xcalloc /src/git/wrapper.c:140:8 #2 0x796870 in
> topo_level_slab_at_peek /src/git/commit-graph.c:71:1 #3 0x7965e0 in
> topo_level_slab_at /src/git/commit-graph.c:71:1 #4 0x78fbf5 in
> compute_topological_levels /src/git/commit-graph.c:1472:12 #5 0x78c5c3
> in write_commit_graph /src/git/commit-graph.c:2456:2 #6 0x535c5f in
> graph_write /src/git/builtin/commit-graph.c:299:6 #7 0x5350ca in
> cmd_commit_graph /src/git/builtin/commit-graph.c:337:11 #8 0x4cddb1 in
> run_builtin /src/git/git.c:453:11 #9 0x4cabe2 in handle_builtin
> /src/git/git.c:704:3 #10 0x4cd084 in run_argv /src/git/git.c:771:4 #11
> 0x4ca424 in cmd_main /src/git/git.c:902:19 #12 0x707fb6 in main
> /src/git/common-main.c:52:11 #13 0x7fee4249383f in __libc_start_main
> (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
>
> SUMMARY: AddressSanitizer: 524264 byte(s) leaked in 2 allocation(s).
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-881%2Fahunt%2Fcommit-graph-leak-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-881/ahunt/commit-graph-leak-v1
> Pull-Request: https://github.com/gitgitgadget/git/pull/881
> commit-graph.c | 1 +
> 1 file changed, 1 insertion(+)
> diff --git a/commit-graph.c b/commit-graph.c
> index ed31843fa522..9529ec552139 100644
> --- a/commit-graph.c
> +++ b/commit-graph.c
> @@ -2471,6 +2471,7 @@ int write_commit_graph(struct object_directory *odb,
> free(ctx->graph_name);
> free(ctx->commits.list);
> oid_array_clear(&ctx->oids);
> + clear_topo_level_slab(&topo_levels);
>
> if (ctx->commit_graph_filenames_after) {
> for (i = 0; i < ctx->num_commit_graphs_after; i++) {
> base-commit: 2283e0e9af55689215afa39c03beb2315ce18e83
> --
> gitgitgadget
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-02-25 6:28 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-02-19 20:13 [PATCH] commit-graph: avoid leaking topo_levels slab in write_commit_graph() Andrzej Hunt via GitGitGadget
2021-02-20 3:36 ` Junio C Hamano
2021-02-22 14:15 ` Derrick Stolee
2021-02-22 19:14 ` Andrzej Hunt
-- strict thread matches above, loose matches on Subject: below --
2021-02-25 6:26 Abhishek Kumar
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