The patch fixes the segmentation fault issue of makedumpfile when a user specifies an invalid file name with -x/--split option. The patch takes care of such a scenario by setting .find_debuginfo to a function pointer which returns -1 and throws error messages against invalid vmlinux file input. With a valid vmlinux file .find_debuginfo was never invoked since the absolute path of debuginfo was known by the time we call init_dwarf_info.
Signed-off-by: Aruna Balakrishnaiah <[email protected]> --- dwarf_info.c | 25 +++++++++++++++++++++++++ 1 files changed, 25 insertions(+), 0 deletions(-) diff --git a/dwarf_info.c b/dwarf_info.c index 46dcd8e..515455d 100644 --- a/dwarf_info.c +++ b/dwarf_info.c @@ -204,6 +204,16 @@ search_module_debuginfo(char *os_release) return FALSE; } +static int +dwarf_no_debuginfo_found(Dwfl_Module *mod, void **userdata, + const char *modname, Dwarf_Addr base, + const char *file_name, + const char *debuglink_file, GElf_Word debuglink_crc, + char **debuginfo_file_name) +{ + return -1; +} + /* * Initialize the dwarf info. * Linux kernel module debuginfo are of ET_REL (relocatable) type. @@ -219,6 +229,21 @@ init_dwarf_info(void) int dwfl_fd = -1; static const Dwfl_Callbacks callbacks = { .section_address = dwfl_offline_section_address, + /* + * By the time init_dwarf_info() function is called, we already + * know absolute path of debuginfo either resolved through + * search_module_debuginfo() call OR user specified vmlinux + * debuginfo through '-x' option. In which case .find_debuginfo + * callback is never invoked. + * But we can not deny a situation where user may pass invalid + * file name through '-x' option, where .find_debuginfo gets + * invoked to find a valid vmlinux debuginfo and hence we run + * into seg fault issue. Hence, set .find_debuginfo to a + * funtion pointer that returns -1 to avoid seg fault and let + * the makedumpfile throw error messages against the invalid + * vmlinux file input. + */ + .find_debuginfo = dwarf_no_debuginfo_found }; dwarf_info.elfd = NULL; _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
