From: Jessica Yu jeyu@kernel.org
commit 5190044c2965514a973184ca68ef5fad57a24670 upstream.
In order to preserve backwards compatability with kmod tools, we have to move the namespace field in Module.symvers last, as the depmod -e -E option looks at the first three fields in Module.symvers to check symbol versions (and it's expected they stay in the original order of crc, symbol, module).
In addition, update an ancient comment above read_dump() in modpost that suggested that the export type field in Module.symvers was optional. I suspect that there were historical reasons behind that comment that are no longer accurate. We have been unconditionally printing the export type since 2.6.18 (commit bd5cbcedf44), which is over a decade ago now.
Fix up read_dump() to treat each field as non-optional. I suspect the original read_dump() code treated the export field as optional in order to support pre <= 2.6.18 Module.symvers (which did not have the export type field). Note that although symbol namespaces are optional, the field will not be omitted from Module.symvers if a symbol does not have a namespace. In this case, the field will simply be empty and the next delimiter or end of line will follow.
Cc: stable@vger.kernel.org Fixes: cb9b55d21fe0 ("modpost: add support for symbol namespaces") Tested-by: Matthias Maennich maennich@google.com Reviewed-by: Matthias Maennich maennich@google.com Reviewed-by: Lucas De Marchi lucas.demarchi@intel.com Signed-off-by: Jessica Yu jeyu@kernel.org Signed-off-by: Masahiro Yamada masahiroy@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- Documentation/kbuild/modules.rst | 4 ++-- scripts/export_report.pl | 2 +- scripts/mod/modpost.c | 24 ++++++++++++------------ 3 files changed, 15 insertions(+), 15 deletions(-)
--- a/Documentation/kbuild/modules.rst +++ b/Documentation/kbuild/modules.rst @@ -470,9 +470,9 @@ build.
The syntax of the Module.symvers file is::
- <CRC> <Symbol> <Namespace> <Module> <Export Type> + <CRC> <Symbol> <Module> <Export Type> <Namespace>
- 0xe1cc2a05 usb_stor_suspend USB_STORAGE drivers/usb/storage/usb-storage EXPORT_SYMBOL_GPL + 0xe1cc2a05 usb_stor_suspend drivers/usb/storage/usb-storage EXPORT_SYMBOL_GPL USB_STORAGE
The fields are separated by tabs and values may be empty (e.g. if no namespace is defined for an exported symbol). --- a/scripts/export_report.pl +++ b/scripts/export_report.pl @@ -94,7 +94,7 @@ if (defined $opt{'o'}) { # while ( <$module_symvers> ) { chomp; - my (undef, $symbol, $namespace, $module, $gpl) = split('\t'); + my (undef, $symbol, $module, $gpl, $namespace) = split('\t'); $SYMBOL { $symbol } = [ $module , "0" , $symbol, $gpl]; } close($module_symvers); --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2433,7 +2433,7 @@ static void write_if_changed(struct buff }
/* parse Module.symvers file. line format: - * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something] + * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace **/ static void read_dump(const char *fname, unsigned int kernel) { @@ -2446,7 +2446,7 @@ static void read_dump(const char *fname, return;
while ((line = get_next_line(&pos, file, size))) { - char *symname, *namespace, *modname, *d, *export, *end; + char *symname, *namespace, *modname, *d, *export; unsigned int crc; struct module *mod; struct symbol *s; @@ -2454,16 +2454,16 @@ static void read_dump(const char *fname, if (!(symname = strchr(line, '\t'))) goto fail; *symname++ = '\0'; - if (!(namespace = strchr(symname, '\t'))) - goto fail; - *namespace++ = '\0'; - if (!(modname = strchr(namespace, '\t'))) + if (!(modname = strchr(symname, '\t'))) goto fail; *modname++ = '\0'; - if ((export = strchr(modname, '\t')) != NULL) - *export++ = '\0'; - if (export && ((end = strchr(export, '\t')) != NULL)) - *end = '\0'; + if (!(export = strchr(modname, '\t'))) + goto fail; + *export++ = '\0'; + if (!(namespace = strchr(export, '\t'))) + goto fail; + *namespace++ = '\0'; + crc = strtoul(line, &d, 16); if (*symname == '\0' || *modname == '\0' || *d != '\0') goto fail; @@ -2514,9 +2514,9 @@ static void write_dump(const char *fname namespace = symbol->namespace; buf_printf(&buf, "0x%08x\t%s\t%s\t%s\t%s\n", symbol->crc, symbol->name, - namespace ? namespace : "", symbol->module->name, - export_str(symbol->export)); + export_str(symbol->export), + namespace ? namespace : ""); } symbol = symbol->next; }