user/sven/linux.git/lib, branch v4.14.231

lib/string: Add strscpy_pad() function

2021-02-23T13:00:30Z

[ Upstream commit 458a3bf82df4fe1f951d0f52b1e0c1e9d5a88a3b ] We have a function to copy strings safely and we have a function to copy strings and zero the tail of the destination (if source string is shorter than destination buffer) but we do not have a function to do both at once. This means developers must write this themselves if they desire this functionality. This is a chore, and also leaves us open to off by one errors unnecessarily. Add a function that calls strscpy() then memset()s the tail to zero if the source string is shorter than the destination buffer. Acked-by: Kees Cook Signed-off-by: Tobin C. Harding Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

lib/genalloc: fix the overflow when size is too big

2021-01-12T19:09:06Z

[ Upstream commit 36845663843fc59c5d794e3dc0641472e3e572da ] Some graphic card has very big memory on chip, such as 32G bytes. In the following case, it will cause overflow: pool = gen_pool_create(PAGE_SHIFT, NUMA_NO_NODE); ret = gen_pool_add(pool, 0x1000000, SZ_32G, NUMA_NO_NODE); va = gen_pool_alloc(pool, SZ_4G); The overflow occurs in gen_pool_alloc_algo_owner(): .... size = nbits << order; .... The @nbits is "int" type, so it will overflow. Then the gen_pool_avail() will return the wrong value. This patch converts some "int" to "unsigned long", and changes the compare code in while. Link: https://lkml.kernel.org/r/20201229060657.3389-1-sjhuang@iluvatar.ai Signed-off-by: Huang Shijie Reported-by: Shi Jiasheng Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

random32: make prandom_u32() output unpredictable

2020-11-18T17:28:00Z

commit c51f8f88d705e06bd696d7510aff22b33eb8e638 upstream. Non-cryptographic PRNGs may have great statistical properties, but are usually trivially predictable to someone who knows the algorithm, given a small sample of their output. An LFSR like prandom_u32() is particularly simple, even if the sample is widely scattered bits. It turns out the network stack uses prandom_u32() for some things like random port numbers which it would prefer are *not* trivially predictable. Predictability led to a practical DNS spoofing attack. Oops. This patch replaces the LFSR with a homebrew cryptographic PRNG based on the SipHash round function, which is in turn seeded with 128 bits of strong random key. (The authors of SipHash have *not* been consulted about this abuse of their algorithm.) Speed is prioritized over security; attacks are rare, while performance is always wanted. Replacing all callers of prandom_u32() is the quick fix. Whether to reinstate a weaker PRNG for uses which can tolerate it is an open question. Commit f227e3ec3b5c ("random32: update the net random state on interrupt and activity") was an earlier attempt at a solution. This patch replaces it. Reported-by: Amit Klein Cc: Willy Tarreau Cc: Eric Dumazet Cc: "Jason A. Donenfeld" Cc: Andy Lutomirski Cc: Kees Cook Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Linus Torvalds Cc: tytso@mit.edu Cc: Florian Westphal Cc: Marc Plumb Fixes: f227e3ec3b5c ("random32: update the net random state on interrupt and activity") Signed-off-by: George Spelvin Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/ [ willy: partial reversal of f227e3ec3b5c; moved SIPROUND definitions to prandom.h for later use; merged George's prandom_seed() proposal; inlined siprand_u32(); replaced the net_rand_state[] array with 4 members to fix a build issue; cosmetic cleanups to make checkpatch happy; fixed RANDOM32_SELFTEST build ] [wt: backported to 4.14 -- various context adjustments; timer API change] Signed-off-by: Willy Tarreau Signed-off-by: Greg Kroah-Hartman

swiotlb: fix "x86: Don't panic if can not alloc buffer for swiotlb"

2020-11-18T17:27:59Z

commit e9696d259d0fb5d239e8c28ca41089838ea76d13 upstream. kernel/dma/swiotlb.c:swiotlb_init gets called first and tries to allocate a buffer for the swiotlb. It does so by calling memblock_alloc_low(PAGE_ALIGN(bytes), PAGE_SIZE); If the allocation must fail, no_iotlb_memory is set. Later during initialization swiotlb-xen comes in (drivers/xen/swiotlb-xen.c:xen_swiotlb_init) and given that io_tlb_start is != 0, it thinks the memory is ready to use when actually it is not. When the swiotlb is actually needed, swiotlb_tbl_map_single gets called and since no_iotlb_memory is set the kernel panics. Instead, if swiotlb-xen.c:xen_swiotlb_init knew the swiotlb hadn't been initialized, it would do the initialization itself, which might still succeed. Fix the panic by setting io_tlb_start to 0 on swiotlb initialization failure, and also by setting no_iotlb_memory to false on swiotlb initialization success. Fixes: ac2cbab21f31 ("x86: Don't panic if can not alloc buffer for swiotlb") Reported-by: Elliott Mitchell Tested-by: Elliott Mitchell Signed-off-by: Stefano Stabellini Reviewed-by: Christoph Hellwig Cc: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman

lib/crc32test: remove extra local_irq_disable/enable

2020-11-10T09:29:04Z

commit aa4e460f0976351fddd2f5ac6e08b74320c277a1 upstream. Commit 4d004099a668 ("lockdep: Fix lockdep recursion") uncovered the following issue in lib/crc32test reported on s390: BUG: using __this_cpu_read() in preemptible [00000000] code: swapper/0/1 caller is lockdep_hardirqs_on_prepare+0x48/0x270 CPU: 6 PID: 1 Comm: swapper/0 Not tainted 5.9.0-next-20201015-15164-g03d992bd2de6 #19 Hardware name: IBM 3906 M04 704 (LPAR) Call Trace: lockdep_hardirqs_on_prepare+0x48/0x270 trace_hardirqs_on+0x9c/0x1b8 crc32_test.isra.0+0x170/0x1c0 crc32test_init+0x1c/0x40 do_one_initcall+0x40/0x130 do_initcalls+0x126/0x150 kernel_init_freeable+0x1f6/0x230 kernel_init+0x22/0x150 ret_from_fork+0x24/0x2c no locks held by swapper/0/1. Remove extra local_irq_disable/local_irq_enable helpers calls. Fixes: 5fb7f87408f1 ("lib: add module support to crc32 tests") Signed-off-by: Vasily Gorbik Signed-off-by: Andrew Morton Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Greg Kroah-Hartman Link: https://lkml.kernel.org/r/patch.git-4369da00c06e.your-ad-here.call-01602859837-ext-1679@work.hours Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Fonts: Replace discarded const qualifier

2020-11-10T09:29:03Z

commit 9522750c66c689b739e151fcdf895420dc81efc0 upstream. Commit 6735b4632def ("Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts") introduced the following error when building rpc_defconfig (only this build appears to be affected): `acorndata_8x8' referenced in section `.text' of arch/arm/boot/compressed/ll_char_wr.o: defined in discarded section `.data' of arch/arm/boot/compressed/font.o `acorndata_8x8' referenced in section `.data.rel.ro' of arch/arm/boot/compressed/font.o: defined in discarded section `.data' of arch/arm/boot/compressed/font.o make[3]: *** [/scratch/linux/arch/arm/boot/compressed/Makefile:191: arch/arm/boot/compressed/vmlinux] Error 1 make[2]: *** [/scratch/linux/arch/arm/boot/Makefile:61: arch/arm/boot/compressed/vmlinux] Error 2 make[1]: *** [/scratch/linux/arch/arm/Makefile:317: zImage] Error 2 The .data section is discarded at link time. Reinstating acorndata_8x8 as const ensures it is still available after linking. Do the same for the other 12 built-in fonts as well, for consistency purposes. Cc: Cc: Russell King Reviewed-by: Greg Kroah-Hartman Fixes: 6735b4632def ("Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts") Signed-off-by: Lee Jones Co-developed-by: Peilin Ye Signed-off-by: Peilin Ye Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20201102183242.2031659-1-yepeilin.cs@gmail.com Signed-off-by: Greg Kroah-Hartman

sgl_alloc_order: fix memory leak

2020-11-05T10:06:58Z

[ Upstream commit b2a182a40278bc5849730e66bca01a762188ed86 ] sgl_alloc_order() can fail when 'length' is large on a memory constrained system. When order > 0 it will potentially be making several multi-page allocations with the later ones more likely to fail than the earlier one. So it is important that sgl_alloc_order() frees up any pages it has obtained before returning NULL. In the case when order > 0 it calls the wrong free page function and leaks. In testing the leak was sufficient to bring down my 8 GiB laptop with OOM. Reviewed-by: Bart Van Assche Signed-off-by: Douglas Gilbert Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

lib/crc32.c: fix trivial typo in preprocessor condition

2020-10-29T08:07:10Z

[ Upstream commit 904542dc56524f921a6bab0639ff6249c01e775f ] Whether crc32_be needs a lookup table is chosen based on CRC_LE_BITS. Obviously, the _be function should be governed by the _BE_ define. This probably never pops up as it's hard to come up with a configuration where CRC_BE_BITS isn't the same as CRC_LE_BITS and as nobody is using bitwise CRC anyway. Fixes: 46c5801eaf86 ("crc32: bolt on crc32c") Signed-off-by: Tobias Jordan Signed-off-by: Andrew Morton Cc: Krzysztof Kozlowski Cc: Jonathan Corbet Cc: Mauro Carvalho Chehab Link: https://lkml.kernel.org/r/20200923182122.GA3338@agrajag.zerfleddert.de Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts

2020-10-14T07:51:10Z

commit 6735b4632def0640dbdf4eb9f99816aca18c4f16 upstream. syzbot has reported an issue in the framebuffer layer, where a malicious user may overflow our built-in font data buffers. In order to perform a reliable range check, subsystems need to know `FONTDATAMAX` for each built-in font. Unfortunately, our font descriptor, `struct console_font` does not contain `FONTDATAMAX`, and is part of the UAPI, making it infeasible to modify it. For user-provided fonts, the framebuffer layer resolves this issue by reserving four extra words at the beginning of data buffers. Later, whenever a function needs to access them, it simply uses the following macros: Recently we have gathered all the above macros to . Let us do the same thing for built-in fonts, prepend four extra words (including `FONTDATAMAX`) to their data buffers, so that subsystems can use these macros for all fonts, no matter built-in or user-provided. This patch depends on patch "fbdev, newport_con: Move FONT_EXTRA_WORDS macros into linux/font.h". Cc: stable@vger.kernel.org Link: https://syzkaller.appspot.com/bug?id=08b8be45afea11888776f897895aef9ad1c3ecfd Signed-off-by: Peilin Ye Reviewed-by: Greg Kroah-Hartman Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/ef18af00c35fb3cc826048a5f70924ed6ddce95b.1600953813.git.yepeilin.cs@gmail.com Signed-off-by: Greg Kroah-Hartman

random32: Restore __latent_entropy attribute on net_rand_state

2020-10-14T07:51:09Z

[ Upstream commit 09a6b0bc3be793ca8cba580b7992d73e9f68f15d ] Commit f227e3ec3b5c ("random32: update the net random state on interrupt and activity") broke compilation and was temporarily fixed by Linus in 83bdc7275e62 ("random32: remove net_rand_state from the latent entropy gcc plugin") by entirely moving net_rand_state out of the things handled by the latent_entropy GCC plugin. From what I understand when reading the plugin code, using the __latent_entropy attribute on a declaration was the wrong part and simply keeping the __latent_entropy attribute on the variable definition was the correct fix. Fixes: 83bdc7275e62 ("random32: remove net_rand_state from the latent entropy gcc plugin") Acked-by: Willy Tarreau Cc: Emese Revfy Signed-off-by: Thibaut Sautereau Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin