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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-03-07 11:49:33 -1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-03-07 11:49:33 -1000 |
| commit | dd047efbe0e086f6ea82774cb239ec4c64a86d76 (patch) | |
| tree | 88116fb4a6b7980ac78d4519599f38fc5928eddc | |
| parent | 6ceb6346b0436ea6591c33ab6ab22e5077ed17e7 (diff) | |
| parent | 39ec9eaaa165d297d008d1fa385748430bd18e4d (diff) | |
Merge tag 'execve-v6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull core dumping fix from Kees Cook:
- Only sort VMAs when core_sort_vma sysctl is set
* tag 'execve-v6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
coredump: Only sort VMAs when core_sort_vma sysctl is set
| -rw-r--r-- | Documentation/admin-guide/sysctl/kernel.rst | 11 | ||||
| -rw-r--r-- | fs/coredump.c | 15 |
2 files changed, 24 insertions, 2 deletions
diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst index a43b78b4b646..dd49a89a62d3 100644 --- a/Documentation/admin-guide/sysctl/kernel.rst +++ b/Documentation/admin-guide/sysctl/kernel.rst @@ -212,6 +212,17 @@ pid>/``). This value defaults to 0. +core_sort_vma +============= + +The default coredump writes VMAs in address order. By setting +``core_sort_vma`` to 1, VMAs will be written from smallest size +to largest size. This is known to break at least elfutils, but +can be handy when dealing with very large (and truncated) +coredumps where the more useful debugging details are included +in the smaller VMAs. + + core_uses_pid ============= diff --git a/fs/coredump.c b/fs/coredump.c index 591700e1b2ce..4375c70144d0 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -63,6 +63,7 @@ static void free_vma_snapshot(struct coredump_params *cprm); static int core_uses_pid; static unsigned int core_pipe_limit; +static unsigned int core_sort_vma; static char core_pattern[CORENAME_MAX_SIZE] = "core"; static int core_name_size = CORENAME_MAX_SIZE; unsigned int core_file_note_size_limit = CORE_FILE_NOTE_SIZE_DEFAULT; @@ -1026,6 +1027,15 @@ static const struct ctl_table coredump_sysctls[] = { .extra1 = (unsigned int *)&core_file_note_size_min, .extra2 = (unsigned int *)&core_file_note_size_max, }, + { + .procname = "core_sort_vma", + .data = &core_sort_vma, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, }; static int __init init_fs_coredump_sysctls(void) @@ -1256,8 +1266,9 @@ static bool dump_vma_snapshot(struct coredump_params *cprm) cprm->vma_data_size += m->dump_size; } - sort(cprm->vma_meta, cprm->vma_count, sizeof(*cprm->vma_meta), - cmp_vma_size, NULL); + if (core_sort_vma) + sort(cprm->vma_meta, cprm->vma_count, sizeof(*cprm->vma_meta), + cmp_vma_size, NULL); return true; } |