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2022-04-27hex2bin: fix access beyond string endMikulas Patocka
If we pass too short string to "hex2bin" (and the string size without the terminating NUL character is even), "hex2bin" reads one byte after the terminating NUL character. This patch fixes it. Note that hex_to_bin returns -1 on error and hex2bin return -EINVAL on error - so we can't just return the variable "hi" or "lo" on error. This inconsistency may be fixed in the next merge window, but for the purpose of fixing this bug, we just preserve the existing behavior and return -1 and -EINVAL. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Fixes: b78049831ffe ("lib: add error checking to hex2bin") Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-04-27hex2bin: make the function hex_to_bin constant-timeMikulas Patocka
The function hex2bin is used to load cryptographic keys into device mapper targets dm-crypt and dm-integrity. It should take constant time independent on the processed data, so that concurrently running unprivileged code can't infer any information about the keys via microarchitectural convert channels. This patch changes the function hex_to_bin so that it contains no branches and no memory accesses. Note that this shouldn't cause performance degradation because the size of the new function is the same as the size of the old function (on x86-64) - and the new function causes no branch misprediction penalties. I compile-tested this function with gcc on aarch64 alpha arm hppa hppa64 i386 ia64 m68k mips32 mips64 powerpc powerpc64 riscv sh4 s390x sparc32 sparc64 x86_64 and with clang on aarch64 arm hexagon i386 mips32 mips64 powerpc powerpc64 s390x sparc32 sparc64 x86_64 to verify that there are no branches in the generated code. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16kernel.h: split out min()/max() et al. helpersAndy Shevchenko
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out min()/max() et al. helpers. At the same time convert users in header and lib folder to use new header. Though for time being include new header back to kernel.h to avoid twisted indirected includes for other existing users. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20200910164152.GA1891694@smile.fi.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-25lib/hexdump: make print_hex_dump_bytes() a nop on !DEBUG buildsStephen Boyd
I'm seeing a bunch of debug prints from a user of print_hex_dump_bytes() in my kernel logs, but I don't have CONFIG_DYNAMIC_DEBUG enabled nor do I have DEBUG defined in my build. The problem is that print_hex_dump_bytes() calls a wrapper function in lib/hexdump.c that calls print_hex_dump() with KERN_DEBUG level. There are three cases to consider here 1. CONFIG_DYNAMIC_DEBUG=y --> call dynamic_hex_dum() 2. CONFIG_DYNAMIC_DEBUG=n && DEBUG --> call print_hex_dump() 3. CONFIG_DYNAMIC_DEBUG=n && !DEBUG --> stub it out Right now, that last case isn't detected and we still call print_hex_dump() from the stub wrapper. Let's make print_hex_dump_bytes() only call print_hex_dump_debug() so that it works properly in all cases. Case #1, print_hex_dump_debug() calls dynamic_hex_dump() and we get same behavior. Case #2, print_hex_dump_debug() calls print_hex_dump() with KERN_DEBUG and we get the same behavior. Case #3, print_hex_dump_debug() is a nop, changing behavior to what we want, i.e. print nothing. Link: http://lkml.kernel.org/r/20190816235624.115280-1-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 501Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation see readme and copying for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 9 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081207.060259192@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-08lib/hexdump.c: return -EINVAL in case of error in hex2bin()Andy Shevchenko
In some cases caller would like to use error code directly without shadowing. -EINVAL feels a rightful code to return in case of error in hex2bin(). Link: http://lkml.kernel.org/r/20170731135510.68023-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06lib/hexdump.c: truncate output in case of overflowAndy Shevchenko
There is a classical off-by-one error in case when we try to place, for example, 1+1 bytes as hex in the buffer of size 6. The expected result is to get an output truncated, but in the reality we get 6 bytes filed followed by terminating NUL. Change the logic how we fill the output in case of byte dumping into limited space. This will follow the snprintf() behaviour by truncating output even on half bytes. Fixes: 114fc1afb2de (hexdump: make it return number of bytes placed in buffer) Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reported-by: Aaro Koskinen <aaro.koskinen@nokia.com> Tested-by: Aaro Koskinen <aaro.koskinen@nokia.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17hexdump: fix for non-aligned buffersHoracio Mijail Anton Quiles
A hexdump with a buf not aligned to the groupsize causes non-naturally-aligned memory accesses. This was causing a kernel panic on the processor BlackFin BF527, when such an unaligned buffer was fed by the function ubifs_scanned_corruption in fs/ubifs/scan.c . To fix this, change accesses to the contents of the buffer so they go through get_unaligned(). This change should be harmless to unaligned- access-capable architectures, and any performance hit should be anyway dwarfed by the snprintf() processing time. Signed-off-by: Horacio Mijail Antón Quiles <hmijail@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: David Howells <dhowells@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Joe Perches <joe@perches.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12hexdump: make it return number of bytes placed in bufferAndy Shevchenko
This patch makes hexdump return the number of bytes placed in the buffer excluding trailing NUL. In the case of overflow it returns the desired amount of bytes to produce the entire dump. Thus, it mimics snprintf(). This will be useful for users that would like to repeat with a bigger buffer. [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12hexdump: do a few calculations aheadAndy Shevchenko
Instead of doing calculations in each case of different groupsize let's do them beforehand. While there, change the switch to an if-else-if construction. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12hexdump: fix ascii column for the tail of a dumpAndy Shevchenko
In the current implementation we have a floating ascii column in the tail of the dump. For example, for row size equal to 16 the ascii column as in following table group size \ length 8 12 16 1 50 50 50 2 22 32 42 4 20 29 38 8 19 - 36 This patch makes it the same independently of amount of bytes dumped. The change is safe since all current users, which use ASCII part of the dump, rely on the group size equal to 1. The patch doesn't change behaviour for such group size (see the table above). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-16Provide a binary to hex conversion functionDavid Howells
Provide a function to convert a buffer of binary data into an unterminated ascii hex string representation of that data. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
2013-09-20lib: introduce upper case hex ascii helpersAndre Naujoks
To be able to use the hex ascii functions in case sensitive environments the array hex_asc_upper[] and the needed functions for hex_byte_pack_upper() are introduced. Signed-off-by: Andre Naujoks <nautsch2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-17dynamic_debug: dynamic hex dumpVladimir Kondratiev
Introduce print_hex_dump_debug() that can be dynamically controlled, similar to pr_debug. Also, make print_hex_dump_bytes() dynamically controlled Implement only 'p' flag (_DPRINTK_FLAGS_PRINT) to keep it simple since hex dump prints multiple lines and long prefix would impact readability. To provide line/file etc. information, use pr_debug or similar before/after print_hex_dump_debug() Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-07lib: reduce the use of module.h wherever possiblePaul Gortmaker
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-09-20lib: add error checking to hex2binMimi Zohar
hex2bin converts a hexadecimal string to its binary representation. The original version of hex2bin did not do any error checking. This patch adds error checking and returns the result. Changelog v1: - removed unpack_hex_byte() - changed return code from boolean to int Changelog: - use the new unpack_hex_byte() - add __must_check compiler option (Andy Shevchenko's suggestion) - change function API to return error checking result (based on Tetsuo Handa's initial patch) Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2011-01-13include/linux/printk.h lib/hexdump.c: neatening and add CONFIG_PRINTK guardJoe Perches
- Move prototypes and align arguments. - Add CONFIG_PRINTK guard for print_hex functions Signed-off-by: Joe Perches <joe@perches.com> Cc: Matt Mackall <mpm@selenic.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-29lib: hex2bin converts ascii hexadecimal string to binaryMimi Zohar
Similar to the kgdb_hex2mem() code, hex2bin converts a string to binary using the hex_to_bin() library call. Changelog: - Replace parameter names with src/dst (based on David Howell's comment) - Add 'const' where needed (based on David Howell's comment) - Replace int with size_t (based on David Howell's comment) Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge E. Hallyn <serge@hallyn.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-05-25lib: introduce common method to convert hex digitsAndy Shevchenko
hex_to_bin() is a little method which converts hex digit to its actual value. There are plenty of places where such functionality is needed. [akpm@linux-foundation.org: use tolower(), saving 3 bytes, test the more common case first - it's quicker] [akpm@linux-foundation.org: relocate tolower to make it even faster! (Joe)] Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com> Cc: Tilman Schmidt <tilman@imap.cc> Cc: Duncan Sands <duncan.sands@free.fr> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: "Richard Russon (FlatCap)" <ldm@flatcap.org> Cc: John W. Linville <linville@tuxdriver.com> Cc: Len Brown <lenb@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25lib/hexdump.c: reduce stack variable size and cleanupsJoe Perches
Reduce char linebuf[200] to the actual size required., which is 32 * 3 + 2 + 32 + 1, ie: linebuf[131]. Change examples to use bool true not int 1. Align multiline argument indentation to open parenthesis. Use temporary for ptr[j] so trigraph fits on single line. Convert printk ptr from %*p, (int)(2 * sizeof(void *)) to %p as %p uses the same calculation for size. Signed-off-by: Joe Perches <joe@perches.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-16hexdump: remove the trailing spaceLi Zefan
For example: hex_dump_to_buffer("AB", 2, 16, 1, buf, 100, 0); pr_info("[%s]\n", buf); I'd expect the output to be "[41 42]", but actually it's "[41 42 ]" This patch also makes the required buf to be minimum. To print the hex format of "AB", a buf with size 6 should be sufficient, but hex_dump_to_buffer() required at least 8. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14lib: create common ascii hex arrayHarvey Harrison
Add a common hex array in hexdump.c so everyone can use it. Add a common hi/lo helper to avoid the shifting masking that is done to get the upper and lower nibbles of a byte value. Pull the pack_hex_byte helper from kgdb as it is opencoded many places in the tree that will be consolidated. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29hexdump: don't print bytes with bit 7 setRandy Dunlap
As Herbert Xu pointed out, bytes (chars) with bit 7 (0x80) set are true with isprint() but they may not be isascii() but be Unicode instead, so don't try to print them in hex dumps. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-11hex_dump: add missing "const" qualifiersAlan Stern
Add missing "const" qualifiers to the print_hex_dump_bytes() library routines. (akpm: rumoured to fix some compile warning somewhere) Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-09hexdump: use const notationArtem Bityutskiy
Trivial fix: mark the buffer to hexdump as const so callers could avoid casting their const buffers when calling print_hex_dump(). The patch is really trivial and I suggest to consider it as a fix (it fixes GCC warnings) and push it to current tree. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-08hexdump: more output formattingRandy Dunlap
Add a prefix string parameter. Callers are responsible for any string length/alignment that they want to see in the output. I.e., callers should pad strings to achieve alignment if they want that. Add rowsize parameter. This is the number of raw data bytes to be printed per line. Must be 16 or 32. Add a groupsize parameter. This allows callers to dump values as 1-byte, 2-byte, 4-byte, or 8-byte numbers. Default is 1-byte numbers. If the total length is not an even multiple of groupsize, 1-byte numbers are printed. Add an "ascii" output parameter. This causes ASCII data output following the hex data output. Clean up some doc examples. Align the ASCII output on all lines that are produced by one call. Add a new interface, print_hex_dump_bytes(), that is a shortcut to print_hex_dump(), using default parameter values to print 16 bytes in byte-size chunks of hex + ASCII output, using printk level KERN_DEBUG. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11lib/hexdumpRandy Dunlap
Based on ace_dump_mem() from Grant Likely for the Xilinx SystemACE CompactFlash interface. Add print_hex_dump() & hex_dumper() to lib/hexdump.c and linux/kernel.h. This patch adds the functions print_hex_dump() & hex_dumper(). print_hex_dump() can be used to perform a hex + ASCII dump of data to syslog, in an easily viewable format, thus providing a common text hex dump format. hex_dumper() provides a dump-to-memory function. It converts one "line" of output (16 bytes of input) at a time. Example usages: print_hex_dump(KERN_DEBUG, DUMP_PREFIX_ADDRESS, frame->data, frame->len); hex_dumper(frame->data, frame->len, linebuf, sizeof(linebuf)); Example output using %DUMP_PREFIX_OFFSET: 0009ab42: 40414243 44454647 48494a4b 4c4d4e4f-@ABCDEFG HIJKLMNO Example output using %DUMP_PREFIX_ADDRESS: ffffffff88089af0: 70717273 74757677 78797a7b 7c7d7e7f-pqrstuvw xyz{|}~. [akpm@linux-foundation.org: cleanups, add export] Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>