CVSS: -EPSS: 0%CPEs: 5EXPL: 0CVE-2021-46962 – mmc: uniphier-sd: Fix a resource leak in the remove function
https://notcve.org/view.php?id=CVE-2021-46962
In the Linux kernel, the following vulnerability has been resolved: mmc: uniphier-sd: Fix a resource leak in the remove function A 'tmio_mmc_host_free()' call is missing in the remove function, in order to balance a 'tmio_mmc_host_alloc()' call in the probe. This is done in the error handling path of the probe, but not in the remove function. Add the missing call. En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mmc: uniphier-sd: corrige una fuga de recursos en la función de eliminación Falta una llamada 'tmio_mmc_host_free()' en la función de eliminación, para equilibrar un 'tmio_mmc_host_alloc()' llamar a la sonda. Esto se hace en la ruta de manejo de errores de la sonda, pero no en la función de eliminación. Agrega la llamada faltante. • https://git.kernel.org/stable/c/3fd784f745dd1747863775a99ec749619ee6759c https://git.kernel.org/stable/c/0d8941b9b2d3e7b3481fdf43b1a6189d162175b7 https://git.kernel.org/stable/c/25ac6ce65f1ab458982d15ec1caf441acd37106a https://git.kernel.org/stable/c/ebe0f12cf4c044f812c6d17011531582f9ac8bb3 https://git.kernel.org/stable/c/d6e7fda496978f2763413b5523557b38dc2bf6c2 https://git.kernel.org/stable/c/e29c84857e2d51aa017ce04284b962742fb97d9e •
CVSS: -EPSS: 0%CPEs: 5EXPL: 0CVE-2021-46961 – irqchip/gic-v3: Do not enable irqs when handling spurious interrups
https://notcve.org/view.php?id=CVE-2021-46961
In the Linux kernel, the following vulnerability has been resolved: irqchip/gic-v3: Do not enable irqs when handling spurious interrups We triggered the following error while running our 4.19 kernel with the pseudo-NMI patches backported to it: [ 14.816231] ------------[ cut here ]------------ [ 14.816231] kernel BUG at irq.c:99! [ 14.816232] Internal error: Oops - BUG: 0 [#1] SMP [ 14.816232] Process swapper/0 (pid: 0, stack limit = 0x(____ptrval____)) [ 14.816233] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 4.19.95.aarch64 #14 [ 14.816233] Hardware name: evb (DT) [ 14.816234] pstate: 80400085 (Nzcv daIf +PAN -UAO) [ 14.816234] pc : asm_nmi_enter+0x94/0x98 [ 14.816235] lr : asm_nmi_enter+0x18/0x98 [ 14.816235] sp : ffff000008003c50 [ 14.816235] pmr_save: 00000070 [ 14.816237] x29: ffff000008003c50 x28: ffff0000095f56c0 [ 14.816238] x27: 0000000000000000 x26: ffff000008004000 [ 14.816239] x25: 00000000015e0000 x24: ffff8008fb916000 [ 14.816240] x23: 0000000020400005 x22: ffff0000080817cc [ 14.816241] x21: ffff000008003da0 x20: 0000000000000060 [ 14.816242] x19: 00000000000003ff x18: ffffffffffffffff [ 14.816243] x17: 0000000000000008 x16: 003d090000000000 [ 14.816244] x15: ffff0000095ea6c8 x14: ffff8008fff5ab40 [ 14.816244] x13: ffff8008fff58b9d x12: 0000000000000000 [ 14.816245] x11: ffff000008c8a200 x10: 000000008e31fca5 [ 14.816246] x9 : ffff000008c8a208 x8 : 000000000000000f [ 14.816247] x7 : 0000000000000004 x6 : ffff8008fff58b9e [ 14.816248] x5 : 0000000000000000 x4 : 0000000080000000 [ 14.816249] x3 : 0000000000000000 x2 : 0000000080000000 [ 14.816250] x1 : 0000000000120000 x0 : ffff0000095f56c0 [ 14.816251] Call trace: [ 14.816251] asm_nmi_enter+0x94/0x98 [ 14.816251] el1_irq+0x8c/0x180 (IRQ C) [ 14.816252] gic_handle_irq+0xbc/0x2e4 [ 14.816252] el1_irq+0xcc/0x180 (IRQ B) [ 14.816253] arch_timer_handler_virt+0x38/0x58 [ 14.816253] handle_percpu_devid_irq+0x90/0x240 [ 14.816253] generic_handle_irq+0x34/0x50 [ 14.816254] __handle_domain_irq+0x68/0xc0 [ 14.816254] gic_handle_irq+0xf8/0x2e4 [ 14.816255] el1_irq+0xcc/0x180 (IRQ A) [ 14.816255] arch_cpu_idle+0x34/0x1c8 [ 14.816255] default_idle_call+0x24/0x44 [ 14.816256] do_idle+0x1d0/0x2c8 [ 14.816256] cpu_startup_entry+0x28/0x30 [ 14.816256] rest_init+0xb8/0xc8 [ 14.816257] start_kernel+0x4c8/0x4f4 [ 14.816257] Code: 940587f1 d5384100 b9401001 36a7fd01 (d4210000) [ 14.816258] Modules linked in: start_dp(O) smeth(O) [ 15.103092] ---[ end trace 701753956cb14aa8 ]--- [ 15.103093] Kernel panic - not syncing: Fatal exception in interrupt [ 15.103099] SMP: stopping secondary CPUs [ 15.103100] Kernel Offset: disabled [ 15.103100] CPU features: 0x36,a2400218 [ 15.103100] Memory Limit: none which is cause by a 'BUG_ON(in_nmi())' in nmi_enter(). From the call trace, we can find three interrupts (noted A, B, C above): interrupt (A) is preempted by (B), which is further interrupted by (C). Subsequent investigations show that (B) results in nmi_enter() being called, but that it actually is a spurious interrupt. Furthermore, interrupts are reenabled in the context of (B), and (C) fires with NMI priority. We end-up with a nested NMI situation, something we definitely do not want to (and cannot) handle. The bug here is that spurious interrupts should never result in any state change, and we should just return to the interrupted context. Moving the handling of spurious interrupts as early as possible in the GICv3 handler fixes this issue. [maz: rewrote commit message, corrected Fixes: tag] En el kernel de Linux, se resolvió la siguiente vulnerabilidad: irqchip/gic-v3: no habilitar irqs cuando se manejan interrupciones espurias. Activamos el siguiente error al ejecutar nuestro kernel 4.19 con los parches pseudo-NMI respaldados: [14.816231] - -----------[ cortar aquí ]------------ ¡ERROR del kernel [14.816231] en irq.c:99! • https://git.kernel.org/stable/c/3f1f3234bc2db1c16b9818b9a15a5d58ad45251c https://git.kernel.org/stable/c/e7ea8e46e3b777be26aa855fe07778c415f24926 https://git.kernel.org/stable/c/7be4db5c2b59fa77071c93ca4329876fb9777202 https://git.kernel.org/stable/c/ea817ac1014c04f47885532b55f5d0898deadfba https://git.kernel.org/stable/c/3f72d3709f53af72835af7dc8b15ba61611a0e36 https://git.kernel.org/stable/c/a97709f563a078e259bf0861cd259aa60332890a •
CVSS: -EPSS: 0%CPEs: 7EXPL: 0CVE-2021-46960 – cifs: Return correct error code from smb2_get_enc_key
https://notcve.org/view.php?id=CVE-2021-46960
In the Linux kernel, the following vulnerability has been resolved: cifs: Return correct error code from smb2_get_enc_key Avoid a warning if the error percolates back up: [440700.376476] CIFS VFS: \\otters.example.com crypt_message: Could not get encryption key [440700.386947] ------------[ cut here ]------------ [440700.386948] err = 1 [440700.386977] WARNING: CPU: 11 PID: 2733 at /build/linux-hwe-5.4-p6lk6L/linux-hwe-5.4-5.4.0/lib/errseq.c:74 errseq_set+0x5c/0x70 ... [440700.397304] CPU: 11 PID: 2733 Comm: tar Tainted: G OE 5.4.0-70-generic #78~18.04.1-Ubuntu ... [440700.397334] Call Trace: [440700.397346] __filemap_set_wb_err+0x1a/0x70 [440700.397419] cifs_writepages+0x9c7/0xb30 [cifs] [440700.397426] do_writepages+0x4b/0xe0 [440700.397444] __filemap_fdatawrite_range+0xcb/0x100 [440700.397455] filemap_write_and_wait+0x42/0xa0 [440700.397486] cifs_setattr+0x68b/0xf30 [cifs] [440700.397493] notify_change+0x358/0x4a0 [440700.397500] utimes_common+0xe9/0x1c0 [440700.397510] do_utimes+0xc5/0x150 [440700.397520] __x64_sys_utimensat+0x88/0xd0 En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: cifs: devuelve el código de error correcto de smb2_get_enc_key Evite una advertencia si el error se repite: [440700.376476] CIFS VFS: \\otters.example.com crypt_message: no se pudo obtener la clave de cifrado [440700.386947] ------------[ cortar aquí ]------------ [440700.386948] err = 1 [440700.386977] ADVERTENCIA: CPU: 11 PID: 2733 en / build/linux-hwe-5.4-p6lk6L/linux-hwe-5.4-5.4.0/lib/errseq.c:74 errseq_set+0x5c/0x70 ... [440700.397304] CPU: 11 PID: 2733 Comm: tar Contaminado: G OE 5.4.0-70-generic #78~18.04.1-Ubuntu... [440700.397334] Seguimiento de llamadas: [440700.397346] __filemap_set_wb_err+0x1a/0x70 [440700.397419] cifs_writepages+0x9c7/0xb30 [cifs ] [440700.397426] do_writepages+0x4b /0xe0 [440700.397444] __filemap_fdatawrite_range+0xcb/0x100 [440700.397455] filemap_write_and_wait+0x42/0xa0 [440700.397486] cifs_setattr+0x68b/0xf30 [cifs] [440700.39749 3] notify_change+0x358/0x4a0 [440700.397500] utimes_common+0xe9/0x1c0 [440700.397510] do_utimes+ 0xc5/0x150 [440700.397520] __x64_sys_utimensat+0x88/0xd0 • https://git.kernel.org/stable/c/61cfac6f267dabcf2740a7ec8a0295833b28b5f5 https://git.kernel.org/stable/c/e94851629c49c65b4fbb29a5725ddfd7988f8f20 https://git.kernel.org/stable/c/e486f8397f3f14a7cadc166138141fdb14379a54 https://git.kernel.org/stable/c/93f3339b22ba17e66f0808737467b70ba087eaec https://git.kernel.org/stable/c/aaa0faa5c28a91c362352d6b35dc3ed10df56fb0 https://git.kernel.org/stable/c/f59a9242942fef0de7b926e438ba4eae65d4b4dd https://git.kernel.org/stable/c/b399c1a3ea0b9d10047ff266d65533df7f15532f https://git.kernel.org/stable/c/83728cbf366e334301091d5b808add468 •
CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2021-46958 – btrfs: fix race between transaction aborts and fsyncs leading to use-after-free
https://notcve.org/view.php?id=CVE-2021-46958
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix race between transaction aborts and fsyncs leading to use-after-free There is a race between a task aborting a transaction during a commit, a task doing an fsync and the transaction kthread, which leads to an use-after-free of the log root tree. When this happens, it results in a stack trace like the following: BTRFS info (device dm-0): forced readonly BTRFS warning (device dm-0): Skipping commit of aborted transaction. BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5) BTRFS warning (device dm-0): Skipping commit of aborted transaction. BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10 BTRFS error (device dm-0): error writing primary super block to device 1 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10 BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers) BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 RIP: 0010:__mutex_lock+0x139/0xa40 Code: c0 74 19 (...) RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202 RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002 RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000 R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040 R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358 FS: 00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? __btrfs_handle_fs_error+0xde/0x146 [btrfs] ? btrfs_sync_log+0x7c1/0xf20 [btrfs] ? btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_file+0x40c/0x580 [btrfs] do_fsync+0x38/0x70 __x64_sys_fsync+0x10/0x20 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa9142a55c3 Code: 8b 15 09 (...) RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3 RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340 R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0 Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...) ---[ end trace ee2f1b19327d791d ]--- The steps that lead to this crash are the following: 1) We are at transaction N; 2) We have two tasks with a transaction handle attached to transaction N. Task A and Task B. • https://git.kernel.org/stable/c/ef67963dac255b293e19815ea3d440567be4626f https://git.kernel.org/stable/c/a4794be7b00b7eda4b45fffd283ab7d76df7e5d6 https://git.kernel.org/stable/c/633f7f216663587f17601eaa1cf2ac3d5654874c https://git.kernel.org/stable/c/e2da98788369bfba1138bada72765c47989a4338 https://git.kernel.org/stable/c/061dde8245356d8864d29e25207aa4daa0be4d3c •
CVSS: 5.5EPSS: 0%CPEs: 2EXPL: 0CVE-2021-46957 – riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe
https://notcve.org/view.php?id=CVE-2021-46957
In the Linux kernel, the following vulnerability has been resolved: riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe The execution of sys_read end up hitting a BUG_ON() in __find_get_block after installing kprobe at sys_read, the BUG message like the following: [ 65.708663] ------------[ cut here ]------------ [ 65.709987] kernel BUG at fs/buffer.c:1251! [ 65.711283] Kernel BUG [#1] [ 65.712032] Modules linked in: [ 65.712925] CPU: 0 PID: 51 Comm: sh Not tainted 5.12.0-rc4 #1 [ 65.714407] Hardware name: riscv-virtio,qemu (DT) [ 65.715696] epc : __find_get_block+0x218/0x2c8 [ 65.716835] ra : __getblk_gfp+0x1c/0x4a [ 65.717831] epc : ffffffe00019f11e ra : ffffffe00019f56a sp : ffffffe002437930 [ 65.719553] gp : ffffffe000f06030 tp : ffffffe0015abc00 t0 : ffffffe00191e038 [ 65.721290] t1 : ffffffe00191e038 t2 : 000000000000000a s0 : ffffffe002437960 [ 65.723051] s1 : ffffffe00160ad00 a0 : ffffffe00160ad00 a1 : 000000000000012a [ 65.724772] a2 : 0000000000000400 a3 : 0000000000000008 a4 : 0000000000000040 [ 65.726545] a5 : 0000000000000000 a6 : ffffffe00191e000 a7 : 0000000000000000 [ 65.728308] s2 : 000000000000012a s3 : 0000000000000400 s4 : 0000000000000008 [ 65.730049] s5 : 000000000000006c s6 : ffffffe00240f800 s7 : ffffffe000f080a8 [ 65.731802] s8 : 0000000000000001 s9 : 000000000000012a s10: 0000000000000008 [ 65.733516] s11: 0000000000000008 t3 : 00000000000003ff t4 : 000000000000000f [ 65.734434] t5 : 00000000000003ff t6 : 0000000000040000 [ 65.734613] status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003 [ 65.734901] Call Trace: [ 65.735076] [<ffffffe00019f11e>] __find_get_block+0x218/0x2c8 [ 65.735417] [<ffffffe00020017a>] __ext4_get_inode_loc+0xb2/0x2f6 [ 65.735618] [<ffffffe000201b6c>] ext4_get_inode_loc+0x3a/0x8a [ 65.735802] [<ffffffe000203380>] ext4_reserve_inode_write+0x2e/0x8c [ 65.735999] [<ffffffe00020357a>] __ext4_mark_inode_dirty+0x4c/0x18e [ 65.736208] [<ffffffe000206bb0>] ext4_dirty_inode+0x46/0x66 [ 65.736387] [<ffffffe000192914>] __mark_inode_dirty+0x12c/0x3da [ 65.736576] [<ffffffe000180dd2>] touch_atime+0x146/0x150 [ 65.736748] [<ffffffe00010d762>] filemap_read+0x234/0x246 [ 65.736920] [<ffffffe00010d834>] generic_file_read_iter+0xc0/0x114 [ 65.737114] [<ffffffe0001f5d7a>] ext4_file_read_iter+0x42/0xea [ 65.737310] [<ffffffe000163f2c>] new_sync_read+0xe2/0x15a [ 65.737483] [<ffffffe000165814>] vfs_read+0xca/0xf2 [ 65.737641] [<ffffffe000165bae>] ksys_read+0x5e/0xc8 [ 65.737816] [<ffffffe000165c26>] sys_read+0xe/0x16 [ 65.737973] [<ffffffe000003972>] ret_from_syscall+0x0/0x2 [ 65.738858] ---[ end trace fe93f985456c935d ]--- A simple reproducer looks like: echo 'p:myprobe sys_read fd=%a0 buf=%a1 count=%a2' > /sys/kernel/debug/tracing/kprobe_events echo 1 > /sys/kernel/debug/tracing/events/kprobes/myprobe/enable cat /sys/kernel/debug/tracing/trace Here's what happens to hit that BUG_ON(): 1) After installing kprobe at entry of sys_read, the first instruction is replaced by 'ebreak' instruction on riscv64 platform. 2) Once kernel reach the 'ebreak' instruction at the entry of sys_read, it trap into the riscv breakpoint handler, where it do something to setup for coming single-step of origin instruction, including backup the 'sstatus' in pt_regs, followed by disable interrupt during single stepping via clear 'SIE' bit of 'sstatus' in pt_regs. 3) Then kernel restore to the instruction slot contains two instructions, one is original instruction at entry of sys_read, the other is 'ebreak'. Here it trigger a 'Instruction page fault' exception (value at 'scause' is '0xc'), if PF is not filled into PageTabe for that slot yet. 4) Again kernel trap into page fault exception handler, where it choose different policy according to the state of running kprobe. Because afte 2) the state is KPROBE_HIT_SS, so kernel reset the current kp ---truncated--- En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: riscv/kprobe: corrige el pánico del kernel al invocar sys_read rastreado por kprobe La ejecución de sys_read termina con un BUG_ON() en __find_get_block después de instalar kprobe en sys_read, el mensaje de ERROR es como el siguiente : [65.708663] ------------[ cortar aquí ]------------ [ 65.709987] ¡ERROR del kernel en fs/buffer.c:1251! [65.711283] ERROR del kernel [#1] [65.712032] Módulos vinculados en: [65.712925] CPU: 0 PID: 51 Comm: sh No contaminado 5.12.0-rc4 #1 [65.714407] Nombre de hardware: riscv-virtio,qemu (DT ) [ 65.715696] epc : __find_get_block+0x218/0x2c8 [ 65.716835] ra : __getblk_gfp+0x1c/0x4a [ 65.717831] epc : ffffffe00019f11e ra : ffffffe00019f56a sp : ffffffe00243 7930 [65.719553] gp: ffffffe000f06030 tp: ffffffe0015abc00 t0: ffffffe00191e038 [65.721290] t1: ffffffe00191e038 t2: 000000000000000a s0: ffffffe002437960 [65.723051] s1: ffffffe00160ad00 a0: ffffffe00160ad00 a1: 000000000000012a [65.724772 ] a2 : 0000000000000400 a3 : 0000000000000008 a4 : 0000000000000040 [ 65.726545] a5 : 00000000000000000 a6 : ffffffe00191e000 a7 : 0000000000000 0000 [65.728308] s2: 000000000000012a s3 : 0000000000000400 s4 : 0000000000000008 [ 65.730049] s5 : 000000000000006c s6 : ffffffe00240f800 s7 : ffffffe000f080a8 [ 65.731802] s8 : 0 000000000000001 s9: 000000000000012a s10: 0000000000000008 [65.733516] s11: 00000000000000008 t3: 00000000000003ff t4: 0000000000 00000f [65.734434] t5: 00000000000003ff t6: 0000000000040000 [65.734613] estado: 0000000000000100 badaddr: 00000000000000000 causa: 0000000000000003 [65.734901] Seguimiento de llamadas: [65.735076] [] __find_get_block+ 0x218/0x2c8 [ 65.735417] [] __ext4_get_inode_loc+0xb2/0x2f6 [ 65.735618] [] ext4_get_inode_loc+0x3a/0x8a [ 65.735802] [] ext4_reserve_inode_write+0x2e/0x8c [ 65.735999] [] __ext4_mark_inode_dirty+0x4c/0x18e [ 65.736208] [] ext4_dirty_inode+0x46/0x66 [ 65.736387] [ ] __mark_inode_dirty+0x12c/0x3da [ 65.736576] [] touch_atime+0x146/0x150 [ 65.736748] [] filemap_read+0x234/0x246 [ 65.736920] [] generic_file_read_iter+0xc0/0x114 [ 65.737114 ] [] ext4_file_read_iter+0x42/0xea [ 65.737310] [] new_sync_read+0xe2/0x15a [ 65.737483] [] vfs_read+0xca/0xf2 [ 65.737641] [] ksys_read+0x5e/0xc8 [ 65.737816] [] sys_read+0xe/0x16 [ 65.737973] [] ret_from_syscall+0x0/0x2 [ 65.738858] ---[ end trace fe93f985456c935d ]--- A El reproductor simple se ve así: echo 'p: myprobe sys_read fd=%a0 buf=%a1 count=%a2' > /sys/kernel/debug/tracing/kprobe_events echo 1 > /sys/kernel/debug/tracing/events/kprobes/myprobe/enable cat /sys/kernel /debug/tracing/trace Esto es lo que sucede cuando se activa ese BUG_ON(): 1) Después de instalar kprobe en la entrada de sys_read, la primera instrucción se reemplaza por la instrucción 'ebreak' en la plataforma riscv64. 2) Una vez que el kernel alcanza la instrucción 'ebreak' en la entrada de sys_read, entra en el controlador de punto de interrupción riscv, donde hace algo para configurar la siguiente instrucción de origen de un solo paso, incluida una copia de seguridad del 'sstatus' en pt_regs, seguido de deshabilite la interrupción durante un solo paso mediante el bit 'SIE' claro de 'sstatus' en pt_regs. 3) Luego, la restauración del kernel en la ranura de instrucciones contiene dos instrucciones, una es la instrucción original en la entrada de sys_read y la otra es 'ebreak'. Aquí se activa una excepción de 'Error en la página de instrucciones' (el valor en 'scause' es '0xc'), si el PF aún no se ha completado en PageTabe para ese espacio. • https://git.kernel.org/stable/c/c22b0bcb1dd024cb9caad9230e3a387d8b061df5 https://git.kernel.org/stable/c/fd0f06590d35c99f98d12c7984897ec4201a6263 https://git.kernel.org/stable/c/b1ebaa0e1318494a7637099a26add50509e37964 •