The max_nr_ranges field of cmem allocated in crash_setup_memmap_entries() is not initialized, its default value is 0.
When elfcorehdr is allocated from the middle of crashk_res due to any potential reason, that is, `image->elf_load_addr > crashk_res.start && image->elf_load_addr + image->elf_headers_sz - 1 < crashk_res.end`, executing memmap_exclude_ranges() will cause a range split to occur in crash_exclude_mem_range(), which eventually leads to an overflow of the cmem->ranges array. Set cmem->max_nr_ranges to 1 to make crash_exclude_mem_range() return -ENOMEM instead of causing cmem->ranges array overflow even when a split happens. Signed-off-by: Yuntao Wang <[email protected]> --- arch/x86/kernel/crash.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index c92d88680dbf..3be46f4b441e 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -282,10 +282,6 @@ int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params) struct crash_memmap_data cmd; struct crash_mem *cmem; - cmem = vzalloc(struct_size(cmem, ranges, 1)); - if (!cmem) - return -ENOMEM; - memset(&cmd, 0, sizeof(struct crash_memmap_data)); cmd.params = params; @@ -321,6 +317,11 @@ int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params) } /* Exclude some ranges from crashk_res and add rest to memmap */ + cmem = vzalloc(struct_size(cmem, ranges, 1)); + if (!cmem) + return -ENOMEM; + cmem->max_nr_ranges = 1; + ret = memmap_exclude_ranges(image, cmem, crashk_res.start, crashk_res.end); if (ret) goto out; -- 2.43.0 _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
