f45765872e
Attempt to modify XRC_TGT QP type from the user space (ibv_xsrq_pingpong invocation) will trigger the following kernel panic. It is caused by the fact that such QPs missed uobject initialization. [ 17.408845] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 [ 17.412645] IP: rdma_lookup_put_uobject+0x9/0x50 [ 17.416567] PGD 0 P4D 0 [ 17.419262] Oops: 0000 [#1] SMP PTI [ 17.422915] CPU: 0 PID: 455 Comm: ibv_xsrq_pingpo Not tainted 4.16.0-rc1+ #86 [ 17.424765] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014 [ 17.427399] RIP: 0010:rdma_lookup_put_uobject+0x9/0x50 [ 17.428445] RSP: 0018:ffffb8c7401e7c90 EFLAGS: 00010246 [ 17.429543] RAX: 0000000000000000 RBX: ffffb8c7401e7cf8 RCX: 0000000000000000 [ 17.432426] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 [ 17.437448] RBP: 0000000000000000 R08: 00000000000218f0 R09: ffffffff8ebc4cac [ 17.440223] R10: fffff6038052cd80 R11: ffff967694b36400 R12: ffff96769391f800 [ 17.442184] R13: ffffb8c7401e7cd8 R14: 0000000000000000 R15: ffff967699f60000 [ 17.443971] FS: 00007fc29207d700(0000) GS:ffff96769fc00000(0000) knlGS:0000000000000000 [ 17.446623] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 17.448059] CR2: 0000000000000048 CR3: 000000001397a000 CR4: 00000000000006b0 [ 17.449677] Call Trace: [ 17.450247] modify_qp.isra.20+0x219/0x2f0 [ 17.451151] ib_uverbs_modify_qp+0x90/0xe0 [ 17.452126] ib_uverbs_write+0x1d2/0x3c0 [ 17.453897] ? __handle_mm_fault+0x93c/0xe40 [ 17.454938] __vfs_write+0x36/0x180 [ 17.455875] vfs_write+0xad/0x1e0 [ 17.456766] SyS_write+0x52/0xc0 [ 17.457632] do_syscall_64+0x75/0x180 [ 17.458631] entry_SYSCALL_64_after_hwframe+0x21/0x86 [ 17.460004] RIP: 0033:0x7fc29198f5a0 [ 17.460982] RSP: 002b:00007ffccc71f018 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 17.463043] RAX: ffffffffffffffda RBX: 0000000000000078 RCX: 00007fc29198f5a0 [ 17.464581] RDX: 0000000000000078 RSI: 00007ffccc71f050 RDI: 0000000000000003 [ 17.466148] RBP: 0000000000000000 R08: 0000000000000078 R09: 00007ffccc71f050 [ 17.467750] R10: 000055b6cf87c248 R11: 0000000000000246 R12: 00007ffccc71f300 [ 17.469541] R13: 000055b6cf8733a0 R14: 0000000000000000 R15: 0000000000000000 [ 17.471151] Code: 00 00 0f 1f 44 00 00 48 8b 47 48 48 8b 00 48 8b 40 10 e9 0b 8b 68 00 90 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 53 89 f5 <48> 8b 47 48 48 89 fb 40 0f b6 f6 48 8b 00 48 8b 40 20 e8 e0 8a [ 17.475185] RIP: rdma_lookup_put_uobject+0x9/0x50 RSP: ffffb8c7401e7c90 [ 17.476841] CR2: 0000000000000048 [ 17.477764] ---[ end trace 1dbcc5354071a712 ]--- [ 17.478880] Kernel panic - not syncing: Fatal exception [ 17.480277] Kernel Offset: 0xd000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) Fixes: 2f08ee363fe0 ("RDMA/restrack: don't use uaccess_kernel()") Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.