Add __counted_by_ptr() to umem_info::buf and umem_info::ranges to improve access bounds checking via CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE.
In check_realloc_usable_mem(), return early on krealloc() failure and use sizeof(*buf) when deriving max_entries from the allocation size. Signed-off-by: Thorsten Blum <[email protected]> --- Changes in v2: - Preserve the original pointer/count assignment order (Sourabh Jain) - v1: https://lore.kernel.org/r/[email protected]/ --- arch/powerpc/kexec/file_load_64.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c index bd80c5fb1b1f..7f45493e7c7a 100644 --- a/arch/powerpc/kexec/file_load_64.c +++ b/arch/powerpc/kexec/file_load_64.c @@ -34,14 +34,14 @@ #include <asm/cputhreads.h> struct umem_info { - __be64 *buf; /* data buffer for usable-memory property */ + __be64 *buf __counted_by_ptr(max_entries); /* data buffer for usable-memory property */ u32 size; /* size allocated for the data buffer */ u32 max_entries; /* maximum no. of entries */ u32 idx; /* index of current entry */ /* usable memory ranges to look up */ unsigned int nr_ranges; - const struct range *ranges; + const struct range *ranges __counted_by_ptr(nr_ranges); }; const struct kexec_file_ops * const kexec_file_loaders[] = { @@ -83,11 +83,12 @@ static __be64 *check_realloc_usable_mem(struct umem_info *um_info, int cnt) new_size = um_info->size + MEM_RANGE_CHUNK_SZ; tbuf = krealloc(um_info->buf, new_size, GFP_KERNEL); - if (tbuf) { - um_info->buf = tbuf; - um_info->size = new_size; - um_info->max_entries = (um_info->size / sizeof(u64)); - } + if (!tbuf) + return NULL; + + um_info->buf = tbuf; + um_info->size = new_size; + um_info->max_entries = um_info->size / sizeof(*um_info->buf); return tbuf; } @@ -288,12 +289,12 @@ static int update_usable_mem_fdt(void *fdt, struct crash_mem *usable_mem) return -EINVAL; } - um_info.buf = NULL; + um_info.buf = NULL; um_info.size = 0; um_info.max_entries = 0; - um_info.idx = 0; + um_info.idx = 0; /* Memory ranges to look up */ - um_info.ranges = &(usable_mem->ranges[0]); + um_info.ranges = usable_mem->ranges; um_info.nr_ranges = usable_mem->nr_ranges; dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
