linux/scripts/kallsyms.c, branch v3.14

revert "kallsyms: fix absolute addresses for kASLR"

2014-03-11T00:26:20Z

Revert the recently applied 0f55159d091c ("kallsyms: fix absolute addresses for kASLR"). Kees said : This got NAKed, please don't apply -- this patch works for x86 and : ARM, but may cause problems for others: : : https://lkml.org/lkml/2014/2/24/718 It appears that Kees will be fixing all this up for 3.15. Cc: Andy Honig Cc: Kees Cook Cc: Michal Marek Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kallsyms: fix absolute addresses for kASLR

2014-03-04T15:55:48Z

Currently symbols that are absolute addresses are incorrectly displayed in /proc/kallsyms if the kernel is loaded with kASLR. The problem was that the scripts/kallsyms.c file which generates the array of symbol names and addresses uses an relocatable value for all symbols, even absolute symbols. This patch fixes that. Several kallsyms output in different boot states for comparison: $ egrep '_(stext|_per_cpu_(start|end))' /root/kallsyms.nokaslr 0000000000000000 D __per_cpu_start 0000000000014280 D __per_cpu_end ffffffff810001c8 T _stext $ egrep '_(stext|_per_cpu_(start|end))' /root/kallsyms.kaslr1 000000001f200000 D __per_cpu_start 000000001f214280 D __per_cpu_end ffffffffa02001c8 T _stext $ egrep '_(stext|_per_cpu_(start|end))' /root/kallsyms.kaslr2 000000000d400000 D __per_cpu_start 000000000d414280 D __per_cpu_end ffffffff8e4001c8 T _stext $ egrep '_(stext|_per_cpu_(start|end))' /root/kallsyms.kaslr-fixed 0000000000000000 D __per_cpu_start 0000000000014280 D __per_cpu_end ffffffffadc001c8 T _stext Signed-off-by: Andy Honig Signed-off-by: Kees Cook Cc: Michal Marek Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild

2013-11-15T22:06:38Z

Pull kbuild changes from Michal Marek: - LTO fixes, but the kallsyms part had to be reverted - Pass -Werror=implicit-int and -Werror=strict-prototypes to the compiler by default - snprintf fix in modpost - remove GREP_OPTIONS from the environment to be immune against exotic grep option settings * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kallsyms: Revert back to 128 max symbol length Kbuild: Ignore GREP_OPTIONS env variable scripts: kallsyms: Use %zu to print 'size_t' scripts/bloat-o-meter: use .startswith rather than fragile slicing scripts/bloat-o-meter: ignore changes in the size of linux_banner kbuild: replace unbounded sprintf call in modpost kbuild, bloat-o-meter: fix static detection Kbuild: Handle longer symbols in kallsyms.c kbuild: Increase kallsyms max symbol length Makefile: enable -Werror=implicit-int and -Werror=strict-prototypes by default

kallsyms: Revert back to 128 max symbol length

2013-11-13T14:58:19Z

This reverts commits f3462aa (Kbuild: Handle longer symbols in kallsyms.c) and eea0e9c (kbuild: Increase kallsyms max symbol length) except for the added overflow check. The reason is a regression caused by increasing the buffer: http://marc.info/?l=linux-kernel&m=138387700415675. Reported-by: Fengguang Wu Cc: Andi Kleen Cc: Joe Mario Signed-off-by: Michal Marek

scripts: kallsyms: Use %zu to print 'size_t'

2013-11-08T09:05:20Z

Commit f3462aa95 (Kbuild: Handle longer symbols in kallsyms.c) introduced the following warning on ARM: scripts/kallsyms.c:121:4: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'size_t' [-Wformat] Use %zu to print 'size_t'. Signed-off-by: Fabio Estevam Signed-off-by: Michal Marek

Kbuild: Handle longer symbols in kallsyms.c

2013-11-06T21:25:49Z

Also warn for too long symbols v2: Add missing newline. Use 255 max (Joe Perches) Signed-off-by: Andi Kleen Signed-off-by: Michal Marek

scripts/kallsyms: filter symbols not in kernel address space

2013-11-01T22:43:02Z

This patch uses CONFIG_PAGE_OFFSET to filter symbols which are not in kernel address space because these symbols are generally for generating code purpose and can't be run at kernel mode, so we needn't keep them in /proc/kallsyms. For example, on ARM there are some symbols which may be linked in relocatable code section, then perf can't parse symbols any more from /proc/kallsyms, this patch fixes the problem (introduced b9b32bf70f2fb710b07c94e13afbc729afe221da) Cc: Russell King Cc: linux-arm-kernel@lists.infradead.org Cc: Michal Marek Signed-off-by: Ming Lei Signed-off-by: Rusty Russell Cc: stable@vger.kernel.org

scripts/kallsyms.c: fix potential segfault

2011-05-12T15:23:40Z

Description: This bug hardly appears during real kernel compiling, because the vmlinux symbols table is huge. But we can still catch it under strict condition , as follows. $ echo "c101b97b T do_fork" | ./scripts/kallsyms --all-symbols #include ...... ...... .globl kallsyms_token_table ALGN kallsyms_token_table: Segmentation fault (core dumped) $ If symbols table is small, all entries in token_profit[0x10000] may decrease to 0 after several calls of compress_symbols() in optimize_result(). In that case, find_best_token() always return 0 and best_table[i] is set to "\0\0" and best_table_len[i] is set to 2. As a result, expand_symbol(best_table[0]="\0\0", best_table_len[0]=2, buf) in write_src() will run in infinite recursion until stack overflows, causing segfault. This patch checks the find_best_token() return value. If all entries in token_profit[0x10000] become 0 according to return value, it breaks the loop in optimize_result(). And expand_symbol() works well when best_table_len[i] is 0. Signed-off-by: Xiaochen Wang Acked-by: Paulo Marques Signed-off-by: Michal Marek

scripts/kallsyms: Enable error messages while hush up unnecessary warnings

2010-09-29T14:18:27Z

As no error was handled, we wouldn't be able to know when an error does occur. The fix preserves error messages while it doesn't let unnecessary compiling warnings show up. Signed-off-by: Jean Sacren Signed-off-by: Michal Marek

scripts/kallsyms: suppress build warning

2010-02-02T13:33:56Z

Suppress a warn_unused_result warning. fgets is called as a part of error handling. It is called just to drop a line and return immediately. read_map is reading the file in a loop and read_symbol reads line by line. So I think there is no point in using return value for useful checking. Other checks like 3 items were returned or !EOF have already been done. Signed-off-by: Himanshu Chauhan Cc: WANG Cong Cc: Michal Marek Signed-off-by: Andrew Morton Signed-off-by: Michal Marek