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* treewide: use get_random_u32_below() instead of deprecated functionJason A. Donenfeld2022-11-181-3/+3
| | | | | | | | | | | | | | | | | | | | This is a simple mechanical transformation done by: @@ expression E; @@ - prandom_u32_max + get_random_u32_below (E) Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Reviewed-by: SeongJae Park <sj@kernel.org> # for damon Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* treewide: use get_random_u32() when possibleJason A. Donenfeld2022-10-111-3/+3
| | | | | | | | | | | | | | | | | | | | | | The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Acked-by: Helge Deller <deller@gmx.de> # for parisc Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* treewide: use prandom_u32_max() when possible, part 1Jason A. Donenfeld2022-10-111-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than incurring a division or requesting too many random bytes for the given range, use the prandom_u32_max() function, which only takes the minimum required bytes from the RNG and avoids divisions. This was done mechanically with this coccinelle script: @basic@ expression E; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u64; @@ ( - ((T)get_random_u32() % (E)) + prandom_u32_max(E) | - ((T)get_random_u32() & ((E) - 1)) + prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2) | - ((u64)(E) * get_random_u32() >> 32) + prandom_u32_max(E) | - ((T)get_random_u32() & ~PAGE_MASK) + prandom_u32_max(PAGE_SIZE) ) @multi_line@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; identifier RAND; expression E; @@ - RAND = get_random_u32(); ... when != RAND - RAND %= (E); + RAND = prandom_u32_max(E); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Add one to the literal. @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1: print("Skipping 0x%x for cleanup elsewhere" % (value)) cocci.include_match(False) elif value & (value + 1) != 0: print("Skipping 0x%x because it's not a power of two minus one" % (value)) cocci.include_match(False) elif literal.startswith('0x'): coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1)) else: coccinelle.RESULT = cocci.make_expr("%d" % (value + 1)) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; expression add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + prandom_u32_max(RESULT) @collapse_ret@ type T; identifier VAR; expression E; @@ { - T VAR; - VAR = (E); - return VAR; + return E; } @drop_var@ type T; identifier VAR; @@ { - T VAR; ... when != VAR } Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: KP Singh <kpsingh@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* lib: fix spelling mistakesZhen Lei2021-07-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix some spelling mistakes in comments: permanentely ==> permanently wont ==> won't remaning ==> remaining succed ==> succeed shouldnt ==> shouldn't alpha-numeric ==> alphanumeric storeing ==> storing funtion ==> function documenation ==> documentation Determin ==> Determine intepreted ==> interpreted ammount ==> amount obious ==> obvious interupts ==> interrupts occured ==> occurred asssociated ==> associated taking into acount ==> taking into account squence ==> sequence stil ==> still contiguos ==> contiguous matchs ==> matches Link: https://lkml.kernel.org/r/20210607072555.12416-1-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rslib: Make some functions staticYueHaibing2019-07-021-6/+6
| | | | | | | | | | | | | | | Fix sparse warnings: lib/reed_solomon/test_rslib.c:313:5: warning: symbol 'ex_rs_helper' was not declared. Should it be static? lib/reed_solomon/test_rslib.c:349:5: warning: symbol 'exercise_rs' was not declared. Should it be static? lib/reed_solomon/test_rslib.c:407:5: warning: symbol 'exercise_rs_bc' was not declared. Should it be static? Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <ferdinand.blomqvist@gmail.com> Link: https://lkml.kernel.org/r/20190702061847.26060-1-yuehaibing@huawei.com
* rslib: Fix remaining decoder flawsFerdinand Blomqvist2019-06-261-20/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The decoder is flawed in the following ways: - The decoder sometimes fails silently, i.e. it announces success but returns a word that is not a codeword. - The return value of the decoder is incoherent with respect to how fixed erasures are counted. If the word to be decoded is a codeword, then the decoder always returns zero even if some erasures are given. On the other hand, if the word to be decoded contains errors, then the number of erasures is always included in the count of corrected symbols. So the decoder handles erasures without symbol corruption inconsistently. This inconsistency probably doesn't affect anyone using the decoder, but it is inconsistent with the documentation. - The error positions returned in eras_pos include all erasures, but the corrections are only set in the correction buffer if there actually is a symbol error. So if there are erasures without symbol corruption, then the correction buffer will contain errors (unless initialized to zero before calling the decoder) or some values will be unset (if the correction buffer is uninitialized). - When correcting data in-place the decoder does not correct errors in the parity. On the other hand, when returning the errors in correction buffers, errors in the parity are included. The respective fixed are: - The syndrome of a codeword is always zero, and the syndrome is linear, .i.e, S(x+e) = S(x) + S(e). So compute the syndrome for the error and check whether it equals the syndrome of the received word. If it does, then we have decoded to a valid codeword, otherwise we know that we have an uncorrectable error. Fortunately, some unrecoverable error conditions can be detected earlier in the decoding, which saves some processing power. - Simply count and return the number of symbols actually corrected. - Make sure to only return positions where symbols were corrected. - Also fix errors in parity when correcting in-place. Another option would be to completely disregard errors in the parity, but then the interface makes it impossible to write tests that test for silent failures. Other changes: - Only fill the correction buffer and error position buffer if both of them are provided. Otherwise correct in place. Previously the error position buffer was always populated with the positions of the corrected errors, irrespective of whether a correction buffer was supplied or not. The rationale for this change is that there seems to be two use cases for the decoder; correct in-place or use the correction buffers. The caller does not need the positions of the corrected errors when in-place correction is used. If in-place correction is not used, then both the correction buffer and error position buffer need to be populated. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-8-ferdinand.blomqvist@gmail.com
* rslib: Update documentationFerdinand Blomqvist2019-06-261-4/+8
| | | | | | | | | | The decoder returns the number of corrected symbols, not bits. The caller provided syndrome must be in index form. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-7-ferdinand.blomqvist@gmail.com
* rslib: Fix handling of of caller provided syndromeFerdinand Blomqvist2019-06-261-2/+12
| | | | | | | | | | Check if the syndrome provided by the caller is zero, and act accordingly. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-6-ferdinand.blomqvist@gmail.com
* rslib: decode_rs: Code cleanupFerdinand Blomqvist2019-06-261-5/+2
| | | | | | | | | | Nothing useful was done after the finish label when count is negative so return directly instead of jumping to finish. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-5-ferdinand.blomqvist@gmail.com
* rslib: decode_rs: Fix length parameter checkFerdinand Blomqvist2019-06-261-1/+1
| | | | | | | | | | | The length of the data load must be at least one. Or in other words, there must be room for at least 1 data and nroots parity symbols after shortening the RS code. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-4-ferdinand.blomqvist@gmail.com
* rslib: Fix decoding of shortened codesFerdinand Blomqvist2019-06-261-2/+2
| | | | | | | | | | | | | | | | | The decoding of shortenend codes is broken. It only works as expected if there are no erasures. When decoding with erasures, Lambda (the error and erasure locator polynomial) is initialized from the given erasure positions. The pad parameter is not accounted for by the initialisation code, and hence Lambda is initialized from incorrect erasure positions. The fix is to adjust the erasure positions by the supplied pad. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-3-ferdinand.blomqvist@gmail.com
* rslib: Add tests for the encoder and decoderFerdinand Blomqvist2019-06-262-1/+519
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A Reed-Solomon code with minimum distance d can correct any error and erasure pattern that satisfies 2 * #error + #erasures < d. If the error correction capacity is exceeded, then correct decoding cannot be guaranteed. The decoder must, however, return a valid codeword or report failure. There are two main tests: - Check for correct behaviour up to the error correction capacity - Check for correct behaviour beyond error corrupted capacity Both tests are simple: 1. Generate random data 2. Encode data with the chosen code 3. Add errors and erasures to data 4. Decode the corrupted word 5. Check for correct behaviour When testing up to capacity we test for: - Correct decoding - Correct return value (i.e. the number of corrected symbols) - That the returned error positions are correct There are two kinds of erasures; the erased symbol can be corrupted or not. When counting the number of corrected symbols, erasures without symbol corruption should not be counted. Similarly, the returned error positions should only include positions where a correction is necessary. We run the up to capacity tests for three different interfaces of decode_rs: - Use the correction buffers - Use the correction buffers with syndromes provided by the caller - Error correction in place (does not check the error positions) When testing beyond capacity test for silent failures. A silent failure is when the decoder returns success but the returned word is not a valid codeword. There are a couple of options for the tests: - Verbosity. - Whether to test for correct behaviour beyond capacity. Default is to test beyond capacity. - Whether to allow erasures without symbol corruption. Defaults to yes. Note that the tests take a couple of minutes to complete. Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190620141039.9874-2-ferdinand.blomqvist@gmail.com
* treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner2019-05-211-0/+1
| | | | | | | | | | | | | | Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* reed_solomon: Fix kernel-docMatthew Wilcox2018-07-101-1/+1
| | | | | | | | | | | | The current doc build warns: ./lib/reed_solomon/reed_solomon.c:287: WARNING: Unknown target name: "gfp". This is because it misinterprets the "GFP_" that is part of the description. Change the description to avoid the problem. Signed-off-by: Matthew Wilcox <willy@infradead.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* treewide: kmalloc() -> kmalloc_array()Kees Cook2018-06-121-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Allocate decoder buffers to avoid VLAsThomas Gleixner2018-04-242-8/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To get rid of the variable length arrays on stack in the RS decoder it's necessary to allocate the decoder buffers per control structure instance. All usage sites have been checked for potential parallel decoder usage and fixed where necessary. Kees confirmed that the pstore decoding is strictly single threaded so there should be no surprises. Allocate them in the rs control structure sized depending on the number of roots for the chosen codec and adapt the decoder code to make use of them. Document the fact that decode operations based on a particular rs control instance cannot run in parallel and the caller has to ensure that as it's not possible to provide a proper locking construct which fits all use cases. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kees Cook <keescook@chromium.org> Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Richard Weinberger <richard@nod.at> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Andrew Morton <akpm@linuxfoundation.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alasdair Kergon <agk@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Split rs control structThomas Gleixner2018-04-243-58/+79
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The decoder library uses variable length arrays on stack. To get rid of them it would be simple to allocate fixed length arrays on stack, but those might become rather large. The other solution is to allocate the buffers in the rs control structure, but this cannot be done as long as the structure can be shared by several users. Sharing is desired because the RS polynom tables are large and initialization is time consuming. To solve this split the codec information out of the control structure and have a pointer to a shared codec in it. Instantiate the control structure for each user, create a new codec if no shareable is avaiable yet. Adjust all affected usage sites to the new scheme. This allows to add per instance decoder buffers to the control structure later on. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Boris Brezillon <boris.brezillon@bootlin.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Richard Weinberger <richard@nod.at> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Andrew Morton <akpm@linuxfoundation.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alasdair Kergon <agk@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Simplify error pathThomas Gleixner2018-04-241-11/+6
| | | | | | | | | | The four error path labels in rs_init() can be reduced to one by allocating the struct with kzalloc so the pointers in the struct are NULL and can be unconditionally handed in to kfree() because they either point to an allocation or are NULL. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Remove GPL boilerplateThomas Gleixner2018-04-241-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | Now that SPDX identifiers are in place, remove the GPL boiler plate text. Leave the notices which document that Phil Karn granted permission in place (encode/decode source code). The modified files are code written for the kernel by me. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Richard Weinberger <richard@nod.at> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Andrew Morton <akpm@linuxfoundation.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alasdair Kergon <agk@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Add SPDX identifiersThomas Gleixner2018-04-243-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Reed-Solomon library is based on code from Phil Karn who granted permission to import it into the kernel under the GPL V2. See commit 15b5423757a7 ("Shared Reed-Solomon ECC library") in the history git tree at: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git ... The encoder/decoder code is lifted from the GPL'd userspace RS-library written by Phil Karn. I modified/wrapped it to provide the different functions which we need in the MTD/NAND code. ... Signed-Off-By: Thomas Gleixner <tglx@linutronix.de> Signed-Off-By: David Woodhouse <dwmw2@infradead.org> "No objections at all. Just keep the authorship notices." -- Phil Karn Add the proper SPDX identifiers according to Documentation/process/license-rules.rst. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Richard Weinberger <richard@nod.at> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Andrew Morton <akpm@linuxfoundation.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alasdair Kergon <agk@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Cleanup top level commentsThomas Gleixner2018-04-243-29/+5
| | | | | | | | | | | | | | | | | | | File references and stale CVS ids are really not useful. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Richard Weinberger <richard@nod.at> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Andrew Morton <akpm@linuxfoundation.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alasdair Kergon <agk@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Cleanup whitespace damageThomas Gleixner2018-04-241-6/+6
| | | | | | | | | | | | | | | | | | | | Instead of mixing the whitespace cleanup into functional changes, mop it up first. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Boris Brezillon <boris.brezillon@free-electrons.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Segher Boessenkool <segher@kernel.crashing.org> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Richard Weinberger <richard@nod.at> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Andrew Morton <akpm@linuxfoundation.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alasdair Kergon <agk@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* rslib: Add GFP aware init functionThomas Gleixner2018-04-241-20/+23
| | | | | | | | | | | | | | The rslib usage in dm/verity_fec is broken because init_rs() can nest in GFP_NOIO mempool allocations as init_rs() is invoked from the mempool alloc callback. Provide a variant which takes gfp_t flags as argument. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Neil Brown <neilb@suse.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* lib: Remove unnecessary inclusions of asm/semaphore.hMatthew Wilcox2008-04-181-1/+0
| | | | | | | reed_solomon doesn't use any of the functionality promised by asm/semaphore.h. Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
* [MTD] [NAND] Replace -1 with -EBADMSG in nand error correction codeJörn Engel2007-10-202-1/+3
| | | | | | | | Magic numerical values are just bad style. Particularly so when undocumented. Signed-off-by: Jörn Engel <joern@logfs.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* [RSLIB] BUG() when passing illegal parameters to decode_rs8() or decode_rs16()Jörn Engel2007-10-201-2/+1
| | | | | | | Returning -ERANGE should never happen. Signed-off-by: Jörn Engel <joern@logfs.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* [RSLIB] Support non-canonical GF representationsSegher Boessenkool2007-05-021-15/+69
| | | | | | | | | | For the CAFÉ NAND controller, we need to support non-canonical representations of the Galois field. Allow the caller to provide its own function for generating the field, and CAFÉ can use rslib instead of its own implementation. Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* fix file specification in commentsUwe Zeisberger2006-10-031-1/+1
| | | | | | | Many files include the filename at the beginning, serveral used a wrong one. Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] reed-solomon: fix kernel-doc commentsRandy Dunlap2006-06-251-9/+2
| | | | | | | | Fix kernel-doc formatting in Reed-Solomon code. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sem2mutex: kernel/Arjan van de Ven2006-03-231-5/+6
| | | | | | | | | | | | Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [LIB] reed_solomon: Clean up trailing white spacesThomas Gleixner2005-11-074-58/+58
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* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-164-0/+667
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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