kernel/linux.git, branch v4.19.27

Linux 4.19.27

2019-03-05T16:58:54+00:00

x86/uaccess: Don't leak the AC flag into __put_user() value evaluation

2019-03-05T16:58:54+00:00

commit 2a418cf3f5f1caf911af288e978d61c9844b0695 upstream. When calling __put_user(foo(), ptr), the __put_user() macro would call foo() in between __uaccess_begin() and __uaccess_end(). If that code were buggy, then those bugs would be run without SMAP protection. Fortunately, there seem to be few instances of the problem in the kernel. Nevertheless, __put_user() should be fixed to avoid doing this. Therefore, evaluate __put_user()'s argument before setting AC. This issue was noticed when an objtool hack by Peter Zijlstra complained about genregs_get() and I compared the assembly output to the C source. [ bp: Massage commit message and fixed up whitespace. ] Fixes: 11f1a4b9755f ("x86: reorganize SMAP handling in user space accesses") Signed-off-by: Andy Lutomirski Signed-off-by: Borislav Petkov Acked-by: Linus Torvalds Cc: Peter Zijlstra Cc: Brian Gerst Cc: Josh Poimboeuf Cc: Denys Vlasenko Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20190225125231.845656645@infradead.org Signed-off-by: Greg Kroah-Hartman

MIPS: eBPF: Fix icache flush end address

2019-03-05T16:58:54+00:00

commit d1a2930d8a992fb6ac2529449f81a0056e1b98d1 upstream. The MIPS eBPF JIT calls flush_icache_range() in order to ensure the icache observes the code that we just wrote. Unfortunately it gets the end address calculation wrong due to some bad pointer arithmetic. The struct jit_ctx target field is of type pointer to u32, and as such adding one to it will increment the address being pointed to by 4 bytes. Therefore in order to find the address of the end of the code we simply need to add the number of 4 byte instructions emitted, but we mistakenly add the number of instructions multiplied by 4. This results in the call to flush_icache_range() operating on a memory region 4x larger than intended, which is always wasteful and can cause crashes if we overrun into an unmapped page. Fix this by correcting the pointer arithmetic to remove the bogus multiplication, and use braces to remove the need for a set of brackets whilst also making it obvious that the target field is a pointer. Signed-off-by: Paul Burton Fixes: b6bd53f9c4e8 ("MIPS: Add missing file for eBPF JIT.") Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Martin KaFai Lau Cc: Song Liu Cc: Yonghong Song Cc: netdev@vger.kernel.org Cc: bpf@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Daniel Borkmann Signed-off-by: Greg Kroah-Hartman

MIPS: BCM63XX: provide DMA masks for ethernet devices

2019-03-05T16:58:54+00:00

commit 18836b48ebae20850631ee2916d0cdbb86df813d upstream. The switch to the generic dma ops made dma masks mandatory, breaking devices having them not set. In case of bcm63xx, it broke ethernet with the following warning when trying to up the device: [ 2.633123] ------------[ cut here ]------------ [ 2.637949] WARNING: CPU: 0 PID: 325 at ./include/linux/dma-mapping.h:516 bcm_enetsw_open+0x160/0xbbc [ 2.647423] Modules linked in: gpio_button_hotplug [ 2.652361] CPU: 0 PID: 325 Comm: ip Not tainted 4.19.16 #0 [ 2.658080] Stack : 80520000 804cd3ec 00000000 00000000 804ccc00 87085bdc 87d3f9d4 804f9a17 [ 2.666707] 8049cf18 00000145 80a942a0 00000204 80ac0000 10008400 87085b90 eb3d5ab7 [ 2.675325] 00000000 00000000 80ac0000 000022b0 00000000 00000000 00000007 00000000 [ 2.683954] 0000007a 80500000 0013b381 00000000 80000000 00000000 804a1664 80289878 [ 2.692572] 00000009 00000204 80ac0000 00000200 00000002 00000000 00000000 80a90000 [ 2.701191] ... [ 2.703701] Call Trace: [ 2.706244] [<8001f3c8>] show_stack+0x58/0x100 [ 2.710840] [<800336e4>] __warn+0xe4/0x118 [ 2.715049] [<800337d4>] warn_slowpath_null+0x48/0x64 [ 2.720237] [<80289878>] bcm_enetsw_open+0x160/0xbbc [ 2.725347] [<802d1d4c>] __dev_open+0xf8/0x16c [ 2.729913] [<802d20cc>] __dev_change_flags+0x100/0x1c4 [ 2.735290] [<802d21b8>] dev_change_flags+0x28/0x70 [ 2.740326] [<803539e0>] devinet_ioctl+0x310/0x7b0 [ 2.745250] [<80355fd8>] inet_ioctl+0x1f8/0x224 [ 2.749939] [<802af290>] sock_ioctl+0x30c/0x488 [ 2.754632] [<80112b34>] do_vfs_ioctl+0x740/0x7dc [ 2.759459] [<80112c20>] ksys_ioctl+0x50/0x94 [ 2.763955] [<800240b8>] syscall_common+0x34/0x58 [ 2.768782] ---[ end trace fb1a6b14d74e28b6 ]--- [ 2.773544] bcm63xx_enetsw bcm63xx_enetsw.0: cannot allocate rx ring 512 Fix this by adding appropriate DMA masks for the platform devices. Fixes: f8c55dc6e828 ("MIPS: use generic dma noncoherent ops for simple noncoherent platforms") Signed-off-by: Jonas Gorski Reviewed-by: Christoph Hellwig Reviewed-by: Florian Fainelli Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Cc: Ralf Baechle Cc: James Hogan Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Greg Kroah-Hartman

MIPS: fix truncation in __cmpxchg_small for short values

2019-03-05T16:58:53+00:00

commit 94ee12b507db8b5876e31c9d6c9d84f556a4b49f upstream. __cmpxchg_small erroneously uses u8 for load comparison which can be either char or short. This patch changes the local variable to u32 which is sufficiently sized, as the loaded value is already masked and shifted appropriately. Using an integer size avoids any unnecessary canonicalization from use of non native widths. This patch is part of a series that adapts the MIPS small word atomics code for xchg and cmpxchg on short and char to RISC-V. Cc: RISC-V Patches Cc: Linux RISC-V Cc: Linux MIPS Signed-off-by: Michael Clark [paul.burton@mips.com: - Fix varialble typo per Jonas Gorski. - Consolidate load variable with other declarations.] Signed-off-by: Paul Burton Fixes: 3ba7f44d2b19 ("MIPS: cmpxchg: Implement 1 byte & 2 byte cmpxchg()") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Greg Kroah-Hartman

hugetlbfs: fix races and page leaks during migration

2019-03-05T16:58:53+00:00

commit cb6acd01e2e43fd8bad11155752b7699c3d0fb76 upstream. hugetlb pages should only be migrated if they are 'active'. The routines set/clear_page_huge_active() modify the active state of hugetlb pages. When a new hugetlb page is allocated at fault time, set_page_huge_active is called before the page is locked. Therefore, another thread could race and migrate the page while it is being added to page table by the fault code. This race is somewhat hard to trigger, but can be seen by strategically adding udelay to simulate worst case scheduling behavior. Depending on 'how' the code races, various BUG()s could be triggered. To address this issue, simply delay the set_page_huge_active call until after the page is successfully added to the page table. Hugetlb pages can also be leaked at migration time if the pages are associated with a file in an explicitly mounted hugetlbfs filesystem. For example, consider a two node system with 4GB worth of huge pages available. A program mmaps a 2G file in a hugetlbfs filesystem. It then migrates the pages associated with the file from one node to another. When the program exits, huge page counts are as follows: node0 1024 free_hugepages 1024 nr_hugepages node1 0 free_hugepages 1024 nr_hugepages Filesystem Size Used Avail Use% Mounted on nodev 4.0G 2.0G 2.0G 50% /var/opt/hugepool That is as expected. 2G of huge pages are taken from the free_hugepages counts, and 2G is the size of the file in the explicitly mounted filesystem. If the file is then removed, the counts become: node0 1024 free_hugepages 1024 nr_hugepages node1 1024 free_hugepages 1024 nr_hugepages Filesystem Size Used Avail Use% Mounted on nodev 4.0G 2.0G 2.0G 50% /var/opt/hugepool Note that the filesystem still shows 2G of pages used, while there actually are no huge pages in use. The only way to 'fix' the filesystem accounting is to unmount the filesystem If a hugetlb page is associated with an explicitly mounted filesystem, this information in contained in the page_private field. At migration time, this information is not preserved. To fix, simply transfer page_private from old to new page at migration time if necessary. There is a related race with removing a huge page from a file and migration. When a huge page is removed from the pagecache, the page_mapping() field is cleared, yet page_private remains set until the page is actually freed by free_huge_page(). A page could be migrated while in this state. However, since page_mapping() is not set the hugetlbfs specific routine to transfer page_private is not called and we leak the page count in the filesystem. To fix that, check for this condition before migrating a huge page. If the condition is detected, return EBUSY for the page. Link: http://lkml.kernel.org/r/74510272-7319-7372-9ea6-ec914734c179@oracle.com Link: http://lkml.kernel.org/r/20190212221400.3512-1-mike.kravetz@oracle.com Fixes: bcc54222309c ("mm: hugetlb: introduce page_huge_active") Signed-off-by: Mike Kravetz Reviewed-by: Naoya Horiguchi Cc: Michal Hocko Cc: Andrea Arcangeli Cc: "Kirill A . Shutemov" Cc: Mel Gorman Cc: Davidlohr Bueso Cc: [mike.kravetz@oracle.com: v2] Link: http://lkml.kernel.org/r/7534d322-d782-8ac6-1c8d-a8dc380eb3ab@oracle.com [mike.kravetz@oracle.com: update comment and changelog] Link: http://lkml.kernel.org/r/420bcfd6-158b-38e4-98da-26d0cd85bd01@oracle.com Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

drm: Block fb changes for async plane updates

2019-03-05T16:58:53+00:00

commit 2216322919c8608a448d7ebc560a845238a5d6b6 upstream. The prepare_fb call always happens on new_plane_state. The drm_atomic_helper_cleanup_planes checks to see if plane state pointer has changed when deciding to call cleanup_fb on either the new_plane_state or the old_plane_state. For a non-async atomic commit the state pointer is swapped, so this helper calls prepare_fb on the new_plane_state and cleanup_fb on the old_plane_state. This makes sense, since we want to prepare the framebuffer we are going to use and cleanup the the framebuffer we are no longer using. For the async atomic update helpers this differs. The async atomic update helpers perform in-place updates on the existing state. They call drm_atomic_helper_cleanup_planes but the state pointer is not swapped. This means that prepare_fb is called on the new_plane_state and cleanup_fb is called on the new_plane_state (not the old). In the case where old_plane_state->fb == new_plane_state->fb then there should be no behavioral difference between an async update and a non-async commit. But there are issues that arise when old_plane_state->fb != new_plane_state->fb. The first is that the new_plane_state->fb is immediately cleaned up after it has been prepared, so we're using a fb that we shouldn't be. The second occurs during a sequence of async atomic updates and non-async regular atomic commits. Suppose there are two framebuffers being interleaved in a double-buffering scenario, fb1 and fb2: - Async update, oldfb = NULL, newfb = fb1, prepare fb1, cleanup fb1 - Async update, oldfb = fb1, newfb = fb2, prepare fb2, cleanup fb2 - Non-async commit, oldfb = fb2, newfb = fb1, prepare fb1, cleanup fb2 We call cleanup_fb on fb2 twice in this example scenario, and any further use will result in use-after-free. The simple fix to this problem is to block framebuffer changes in the drm_atomic_helper_async_check function for now. v2: Move check by itself, add a FIXME (Daniel) Cc: Daniel Vetter Cc: Harry Wentland Cc: Andrey Grodzovsky Cc: # v4.14+ Fixes: fef9df8b5945 ("drm/atomic: initial support for asynchronous plane update") Signed-off-by: Nicholas Kazlauskas Acked-by: Andrey Grodzovsky Acked-by: Harry Wentland Reviewed-by: Daniel Vetter Signed-off-by: Harry Wentland Link: https://patchwork.freedesktop.org/patch/275364/ Signed-off-by: Dave Airlie Signed-off-by: Greg Kroah-Hartman

mm: enforce min addr even if capable() in expand_downwards()

2019-03-05T16:58:53+00:00

commit 0a1d52994d440e21def1c2174932410b4f2a98a1 upstream. security_mmap_addr() does a capability check with current_cred(), but we can reach this code from contexts like a VFS write handler where current_cred() must not be used. This can be abused on systems without SMAP to make NULL pointer dereferences exploitable again. Fixes: 8869477a49c3 ("security: protect from stack expansion into low vm addresses") Cc: stable@kernel.org Signed-off-by: Jann Horn Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mmc: sdhci-esdhc-imx: correct the fix of ERR004536

2019-03-05T16:58:53+00:00

commit e30be063d6dbcc0f18b1eb25fa709fdef89201fb upstream. Commit 18094430d6b5 ("mmc: sdhci-esdhc-imx: add ADMA Length Mismatch errata fix") involve the fix of ERR004536, but the fix is incorrect. Double confirm with IC, need to clear the bit 7 of register 0x6c rather than set this bit 7. Here is the definition of bit 7 of 0x6c: 0: enable the new IC fix for ERR004536 1: do not use the IC fix, keep the same as before Find this issue on i.MX845s-evk board when enable CMDQ, and let system in heavy loading. root@imx8mmevk:~# dd if=/dev/mmcblk2 of=/dev/null bs=1M & root@imx8mmevk:~# memtester 1000M > /dev/zero & root@imx8mmevk:~# [ 139.897220] mmc2: cqhci: timeout for tag 16 [ 139.901417] mmc2: cqhci: ============ CQHCI REGISTER DUMP =========== [ 139.907862] mmc2: cqhci: Caps: 0x0000310a | Version: 0x00000510 [ 139.914311] mmc2: cqhci: Config: 0x00001001 | Control: 0x00000000 [ 139.920753] mmc2: cqhci: Int stat: 0x00000000 | Int enab: 0x00000006 [ 139.927193] mmc2: cqhci: Int sig: 0x00000006 | Int Coal: 0x00000000 [ 139.933634] mmc2: cqhci: TDL base: 0x7809c000 | TDL up32: 0x00000000 [ 139.940073] mmc2: cqhci: Doorbell: 0x00030000 | TCN: 0x00000000 [ 139.946518] mmc2: cqhci: Dev queue: 0x00010000 | Dev Pend: 0x00010000 [ 139.952967] mmc2: cqhci: Task clr: 0x00000000 | SSC1: 0x00011000 [ 139.959411] mmc2: cqhci: SSC2: 0x00000001 | DCMD rsp: 0x00000000 [ 139.965857] mmc2: cqhci: RED mask: 0xfdf9a080 | TERRI: 0x00000000 [ 139.972308] mmc2: cqhci: Resp idx: 0x0000002e | Resp arg: 0x00000900 [ 139.978761] mmc2: sdhci: ============ SDHCI REGISTER DUMP =========== [ 139.985214] mmc2: sdhci: Sys addr: 0xb2c19000 | Version: 0x00000002 [ 139.991669] mmc2: sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000400 [ 139.998127] mmc2: sdhci: Argument: 0x40110400 | Trn mode: 0x00000033 [ 140.004618] mmc2: sdhci: Present: 0x01088a8f | Host ctl: 0x00000030 [ 140.011113] mmc2: sdhci: Power: 0x00000002 | Blk gap: 0x00000080 [ 140.017583] mmc2: sdhci: Wake-up: 0x00000008 | Clock: 0x0000000f [ 140.024039] mmc2: sdhci: Timeout: 0x0000008f | Int stat: 0x00000000 [ 140.030497] mmc2: sdhci: Int enab: 0x107f4000 | Sig enab: 0x107f4000 [ 140.036972] mmc2: sdhci: AC12 err: 0x00000000 | Slot int: 0x00000502 [ 140.043426] mmc2: sdhci: Caps: 0x07eb0000 | Caps_1: 0x8000b407 [ 140.049867] mmc2: sdhci: Cmd: 0x00002c1a | Max curr: 0x00ffffff [ 140.056314] mmc2: sdhci: Resp[0]: 0x00000900 | Resp[1]: 0xffffffff [ 140.062755] mmc2: sdhci: Resp[2]: 0x328f5903 | Resp[3]: 0x00d00f00 [ 140.069195] mmc2: sdhci: Host ctl2: 0x00000008 [ 140.073640] mmc2: sdhci: ADMA Err: 0x00000007 | ADMA Ptr: 0x7809c108 [ 140.080079] mmc2: sdhci: ============================================ [ 140.086662] mmc2: running CQE recovery Fixes: 18094430d6b5 ("mmc: sdhci-esdhc-imx: add ADMA Length Mismatch errata fix") Signed-off-by: Haibo Chen Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman

mmc: cqhci: Fix a tiny potential memory leak on error condition

2019-03-05T16:58:53+00:00

commit d07e9fadf3a6b466ca3ae90fa4859089ff20530f upstream. Free up the allocated memory in the case of error return The value of mmc_host->cqe_enabled stays 'false'. Thus, cqhci_disable (mmc_cqe_ops->cqe_disable) won't be called to free the memory. Also, cqhci_disable() seems to be designed to disable and free all resources, not suitable to handle this corner case. Fixes: a4080225f51d ("mmc: cqhci: support for command queue enabled host") Signed-off-by: Alamy Liu Acked-by: Adrian Hunter Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman