This patch makes a couple of small cleanups to parameter checking of libfdt functions.
- In several functions which take a node offset, we use an idiom involving fdt_next_tag() first to check that we have indeed been given a node offset. This patch adds a helper function _fdt_check_node_offset() to encapsulate this usage of fdt_next_tag().
- In fdt_rw.c in several places we have the expanded version of the RW_CHECK_HEADER() macro for no particular reason. This patch replaces those instances with an invocation of the macro; that's what it's for.
- In fdt_sw.c we rename the check_header_sw() function to sw_check_header() to match the analgous function in fdt_rw.c, and we provide an SW_CHECK_HEADER() wrapper macro as RW_CHECK_HEADER() functions in fdt_rw.c
Signed-off-by: David Gibson david@gibson.dropbear.id.au ---
These are improvements pulled in from the DTC/libfdt project. The original patch was published:
Date: Tue, 20 May 2008 17:19:11 +1000
Best regards, gvb
libfdt/fdt.c | 17 ++++++++++++----- libfdt/fdt_ro.c | 26 ++++++++------------------ libfdt/fdt_rw.c | 24 ++++++++---------------- libfdt/fdt_sw.c | 31 +++++++++++++++---------------- libfdt/libfdt_internal.h | 1 + 5 files changed, 44 insertions(+), 55 deletions(-)
diff --git a/libfdt/fdt.c b/libfdt/fdt.c index bd91712..0d16427 100644 --- a/libfdt/fdt.c +++ b/libfdt/fdt.c @@ -129,16 +129,23 @@ uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset) return tag; }
+int _fdt_check_node_offset(const void *fdt, int offset) +{ + if ((offset < 0) || (offset % FDT_TAGSIZE) + || (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE)) + return -FDT_ERR_BADOFFSET; + + return offset; +} + int fdt_next_node(const void *fdt, int offset, int *depth) { int nextoffset = 0; uint32_t tag;
- if (offset >= 0) { - tag = fdt_next_tag(fdt, offset, &nextoffset); - if (tag != FDT_BEGIN_NODE) - return -FDT_ERR_BADOFFSET; - } + if (offset >= 0) + if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0) + return nextoffset;
do { offset = nextoffset; diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c index 63fa129..e55872f 100644 --- a/libfdt/fdt_ro.c +++ b/libfdt/fdt_ro.c @@ -157,16 +157,12 @@ int fdt_path_offset(const void *fdt, const char *path)
const char *fdt_get_name(const void *fdt, int nodeoffset, int *len) { - const struct fdt_node_header *nh; + const struct fdt_node_header *nh = _fdt_offset_ptr(fdt, nodeoffset); int err;
- if ((err = fdt_check_header(fdt)) != 0) - goto fail; - - err = -FDT_ERR_BADOFFSET; - nh = fdt_offset_ptr(fdt, nodeoffset, sizeof(*nh)); - if (!nh || (fdt32_to_cpu(nh->tag) != FDT_BEGIN_NODE)) - goto fail; + if (((err = fdt_check_header(fdt)) != 0) + || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0)) + goto fail;
if (len) *len = strlen(nh->name); @@ -189,17 +185,11 @@ const struct fdt_property *fdt_get_property(const void *fdt, int offset, nextoffset; int err;
- if ((err = fdt_check_header(fdt)) != 0) - goto fail; - - err = -FDT_ERR_BADOFFSET; - if (nodeoffset % FDT_TAGSIZE) - goto fail; - - tag = fdt_next_tag(fdt, nodeoffset, &nextoffset); - if (tag != FDT_BEGIN_NODE) - goto fail; + if (((err = fdt_check_header(fdt)) != 0) + || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0)) + goto fail;
+ nextoffset = err; do { offset = nextoffset;
diff --git a/libfdt/fdt_rw.c b/libfdt/fdt_rw.c index 0df472b..ec0738c 100644 --- a/libfdt/fdt_rw.c +++ b/libfdt/fdt_rw.c @@ -172,8 +172,7 @@ int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size) struct fdt_reserve_entry *re; int err;
- if ((err = rw_check_header(fdt))) - return err; + RW_CHECK_HEADER(fdt);
re = _fdt_mem_rsv_w(fdt, fdt_num_mem_rsv(fdt)); err = _blob_splice_mem_rsv(fdt, re, 0, 1); @@ -190,8 +189,8 @@ int fdt_del_mem_rsv(void *fdt, int n) struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n); int err;
- if ((err = rw_check_header(fdt))) - return err; + RW_CHECK_HEADER(fdt); + if (n >= fdt_num_mem_rsv(fdt)) return -FDT_ERR_NOTFOUND;
@@ -223,15 +222,13 @@ static int _resize_property(void *fdt, int nodeoffset, const char *name, int len static int _add_property(void *fdt, int nodeoffset, const char *name, int len, struct fdt_property **prop) { - uint32_t tag; int proplen; int nextoffset; int namestroff; int err;
- tag = fdt_next_tag(fdt, nodeoffset, &nextoffset); - if (tag != FDT_BEGIN_NODE) - return -FDT_ERR_BADOFFSET; + if ((nextoffset = _fdt_check_node_offset(fdt, nodeoffset)) < 0) + return nextoffset;
namestroff = _find_add_string(fdt, name); if (namestroff < 0) @@ -256,8 +253,7 @@ int fdt_set_name(void *fdt, int nodeoffset, const char *name) int oldlen, newlen; int err;
- if ((err = rw_check_header(fdt))) - return err; + RW_CHECK_HEADER(fdt);
namep = (char *)fdt_get_name(fdt, nodeoffset, &oldlen); if (!namep) @@ -280,8 +276,7 @@ int fdt_setprop(void *fdt, int nodeoffset, const char *name, struct fdt_property *prop; int err;
- if ((err = rw_check_header(fdt))) - return err; + RW_CHECK_HEADER(fdt);
err = _resize_property(fdt, nodeoffset, name, len, &prop); if (err == -FDT_ERR_NOTFOUND) @@ -452,11 +447,8 @@ int fdt_open_into(const void *fdt, void *buf, int bufsize) int fdt_pack(void *fdt) { int mem_rsv_size; - int err;
- err = rw_check_header(fdt); - if (err) - return err; + RW_CHECK_HEADER(fdt);
mem_rsv_size = (fdt_num_mem_rsv(fdt)+1) * sizeof(struct fdt_reserve_entry); diff --git a/libfdt/fdt_sw.c b/libfdt/fdt_sw.c index dda2de3..df09876 100644 --- a/libfdt/fdt_sw.c +++ b/libfdt/fdt_sw.c @@ -55,13 +55,21 @@
#include "libfdt_internal.h"
-static int check_header_sw(void *fdt) +static int sw_check_header(void *fdt) { if (fdt_magic(fdt) != SW_MAGIC) return -FDT_ERR_BADMAGIC; + /* FIXME: should check more details about the header state */ return 0; }
+#define SW_CHECK_HEADER(fdt) \ + { \ + int err; \ + if ((err = sw_check_header(fdt)) != 0) \ + return err; \ + } + static void *grab_space(void *fdt, int len) { int offset = fdt_size_dt_struct(fdt); @@ -102,11 +110,10 @@ int fdt_create(void *buf, int bufsize) int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size) { struct fdt_reserve_entry *re; - int err = check_header_sw(fdt); int offset;
- if (err) - return err; + SW_CHECK_HEADER(fdt); + if (fdt_size_dt_struct(fdt)) return -FDT_ERR_BADSTATE;
@@ -131,11 +138,9 @@ int fdt_finish_reservemap(void *fdt) int fdt_begin_node(void *fdt, const char *name) { struct fdt_node_header *nh; - int err = check_header_sw(fdt); int namelen = strlen(name) + 1;
- if (err) - return err; + SW_CHECK_HEADER(fdt);
nh = grab_space(fdt, sizeof(*nh) + ALIGN(namelen, FDT_TAGSIZE)); if (! nh) @@ -149,10 +154,8 @@ int fdt_begin_node(void *fdt, const char *name) int fdt_end_node(void *fdt) { uint32_t *en; - int err = check_header_sw(fdt);
- if (err) - return err; + SW_CHECK_HEADER(fdt);
en = grab_space(fdt, FDT_TAGSIZE); if (! en) @@ -188,11 +191,9 @@ static int find_add_string(void *fdt, const char *s) int fdt_property(void *fdt, const char *name, const void *val, int len) { struct fdt_property *prop; - int err = check_header_sw(fdt); int nameoff;
- if (err) - return err; + SW_CHECK_HEADER(fdt);
nameoff = find_add_string(fdt, name); if (nameoff == 0) @@ -211,15 +212,13 @@ int fdt_property(void *fdt, const char *name, const void *val, int len)
int fdt_finish(void *fdt) { - int err = check_header_sw(fdt); char *p = (char *)fdt; uint32_t *end; int oldstroffset, newstroffset; uint32_t tag; int offset, nextoffset;
- if (err) - return err; + SW_CHECK_HEADER(fdt);
/* Add terminator */ end = grab_space(fdt, sizeof(*end)); diff --git a/libfdt/libfdt_internal.h b/libfdt/libfdt_internal.h index 52e1b8d..f72e70d 100644 --- a/libfdt/libfdt_internal.h +++ b/libfdt/libfdt_internal.h @@ -66,6 +66,7 @@ }
uint32_t _fdt_next_tag(const void *fdt, int startoffset, int *nextoffset); +int _fdt_check_node_offset(const void *fdt, int offset); const char *_fdt_find_string(const char *strtab, int tabsize, const char *s); int _fdt_node_end_offset(void *fdt, int nodeoffset);