Message ID | 20210630091408.10053-1-colin.king@canonical.com |
---|---|
State | New |
Headers | show |
Series | [SRU,Groovy,Hirsute,Impish] UBUNTU: ubuntu-host: add generic lseek op | expand |
On 30/06/2021 10:14, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > BugLink: https://bugs.launchpad.net/1934110 Bah, that should be: BugLink: https://bugs.launchpad.net/bugs/1934110 ..can that be fixed up when it is applied, or shall I send a V2? > > Currently the lseek op is null and seeking on the esm-token procfs > file will cause an oops as detected by the stress-ng procfs stressor > as shown by the following splat: > > [ 942.470568] BUG: kernel NULL pointer dereference, address: 0000000000000000 > [ 942.471157] #PF: supervisor instruction fetch in kernel mode > [ 942.471724] #PF: error_code(0x0010) - not-present page > [ 942.472297] PGD 0 P4D 0 > [ 942.472867] Oops: 0010 [#1] SMP PTI > [ 942.473435] CPU: 2 PID: 5661 Comm: stress-ng Not tainted 5.13.0-9-generic #9 > [ 942.474012] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > [ 942.474599] RIP: 0010:0x0 > [ 942.475194] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. > [ 942.475792] RSP: 0018:ffffaacf80ff7eb8 EFLAGS: 00010246 > [ 942.476383] RAX: 0000000000000000 RBX: ffff9eaa8a175240 RCX: 0000000000000001 > [ 942.476986] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9eaa838d5800 > [ 942.477600] RBP: ffffaacf80ff7ed0 R08: 0000000000004000 R09: 0000000000000004 > [ 942.478203] R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 > [ 942.478800] R13: 0000000000000000 R14: ffffffffffffffea R15: ffff9eaa838d5800 > [ 942.479399] FS: 00007f998d487f00(0000) GS:ffff9eaaffc80000(0000) knlGS:0000000000000000 > [ 942.480006] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 942.480607] CR2: ffffffffffffffd6 CR3: 000000010a774002 CR4: 0000000000370ee0 > [ 942.481219] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 942.481855] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 942.482458] Call Trace: > [ 942.483052] proc_reg_llseek+0x4e/0x80 > [ 942.483646] ? __fdget_pos+0x43/0x50 > [ 942.484234] ksys_lseek+0x84/0xc0 > [ 942.484815] __x64_sys_lseek+0x1a/0x20 > [ 942.485412] do_syscall_64+0x61/0xb0 > [ 942.485966] ? asm_exc_page_fault+0x8/0x30 > [ 942.486476] entry_SYSCALL_64_after_hwframe+0x44/0xae > [ 942.486994] RIP: 0033:0x7f998d5c1cdb > [ 942.487512] Code: ff ff c3 0f 1f 40 00 48 8b 15 89 81 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa b8 08 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 59 81 0d 00 f7 d8 > [ 942.488593] RSP: 002b:00007ffdf61c5328 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 > [ 942.489148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f998d5c1cdb > [ 942.489710] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 > [ 942.490252] RBP: 0000000000000004 R08: 000001785e4740dd R09: 0000562dbebb9e50 > [ 942.490801] R10: 00007ffdf61c5300 R11: 0000000000000246 R12: 00007ffdf61c63f0 > [ 942.491354] R13: 00007ffdf61c53f0 R14: 0000000000000003 R15: 00000000000001e9 > > Fix this by using the generic lseek operation. > > Fixes: 71adefd254f2 ("UBUNTU: Add ubuntu-host module") > Signed-off-by: Colin Ian King <colin.king@canonical.com> > --- > ubuntu/ubuntu-host/ubuntu-host.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/ubuntu/ubuntu-host/ubuntu-host.c b/ubuntu/ubuntu-host/ubuntu-host.c > index 1abd402..a4c0636 100644 > --- a/ubuntu/ubuntu-host/ubuntu-host.c > +++ b/ubuntu/ubuntu-host/ubuntu-host.c > @@ -38,6 +38,8 @@ static ssize_t esm_token_write(struct file *f, const char __user *buf, > static const struct proc_ops esm_token_fops = { > .proc_read = esm_token_read, > .proc_write = esm_token_write, > + .proc_lseek = default_llseek, > + > }; > > static void ubuntu_host_cleanup(void) >
On 30.06.21 11:16, Colin Ian King wrote: > On 30/06/2021 10:14, Colin King wrote: >> From: Colin Ian King <colin.king@canonical.com> >> >> BugLink: https://bugs.launchpad.net/1934110 > > Bah, that should be: > > BugLink: https://bugs.launchpad.net/bugs/1934110 > > ..can that be fixed up when it is applied, or shall I send a V2? Can be fixed when applying. > >> >> Currently the lseek op is null and seeking on the esm-token procfs >> file will cause an oops as detected by the stress-ng procfs stressor >> as shown by the following splat: >> >> [ 942.470568] BUG: kernel NULL pointer dereference, address: 0000000000000000 >> [ 942.471157] #PF: supervisor instruction fetch in kernel mode >> [ 942.471724] #PF: error_code(0x0010) - not-present page >> [ 942.472297] PGD 0 P4D 0 >> [ 942.472867] Oops: 0010 [#1] SMP PTI >> [ 942.473435] CPU: 2 PID: 5661 Comm: stress-ng Not tainted 5.13.0-9-generic #9 >> [ 942.474012] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 >> [ 942.474599] RIP: 0010:0x0 >> [ 942.475194] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. >> [ 942.475792] RSP: 0018:ffffaacf80ff7eb8 EFLAGS: 00010246 >> [ 942.476383] RAX: 0000000000000000 RBX: ffff9eaa8a175240 RCX: 0000000000000001 >> [ 942.476986] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9eaa838d5800 >> [ 942.477600] RBP: ffffaacf80ff7ed0 R08: 0000000000004000 R09: 0000000000000004 >> [ 942.478203] R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 >> [ 942.478800] R13: 0000000000000000 R14: ffffffffffffffea R15: ffff9eaa838d5800 >> [ 942.479399] FS: 00007f998d487f00(0000) GS:ffff9eaaffc80000(0000) knlGS:0000000000000000 >> [ 942.480006] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> [ 942.480607] CR2: ffffffffffffffd6 CR3: 000000010a774002 CR4: 0000000000370ee0 >> [ 942.481219] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >> [ 942.481855] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >> [ 942.482458] Call Trace: >> [ 942.483052] proc_reg_llseek+0x4e/0x80 >> [ 942.483646] ? __fdget_pos+0x43/0x50 >> [ 942.484234] ksys_lseek+0x84/0xc0 >> [ 942.484815] __x64_sys_lseek+0x1a/0x20 >> [ 942.485412] do_syscall_64+0x61/0xb0 >> [ 942.485966] ? asm_exc_page_fault+0x8/0x30 >> [ 942.486476] entry_SYSCALL_64_after_hwframe+0x44/0xae >> [ 942.486994] RIP: 0033:0x7f998d5c1cdb >> [ 942.487512] Code: ff ff c3 0f 1f 40 00 48 8b 15 89 81 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa b8 08 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 59 81 0d 00 f7 d8 >> [ 942.488593] RSP: 002b:00007ffdf61c5328 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 >> [ 942.489148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f998d5c1cdb >> [ 942.489710] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 >> [ 942.490252] RBP: 0000000000000004 R08: 000001785e4740dd R09: 0000562dbebb9e50 >> [ 942.490801] R10: 00007ffdf61c5300 R11: 0000000000000246 R12: 00007ffdf61c63f0 >> [ 942.491354] R13: 00007ffdf61c53f0 R14: 0000000000000003 R15: 00000000000001e9 >> >> Fix this by using the generic lseek operation. >> >> Fixes: 71adefd254f2 ("UBUNTU: Add ubuntu-host module") >> Signed-off-by: Colin Ian King <colin.king@canonical.com> >> --- >> ubuntu/ubuntu-host/ubuntu-host.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/ubuntu/ubuntu-host/ubuntu-host.c b/ubuntu/ubuntu-host/ubuntu-host.c >> index 1abd402..a4c0636 100644 >> --- a/ubuntu/ubuntu-host/ubuntu-host.c >> +++ b/ubuntu/ubuntu-host/ubuntu-host.c >> @@ -38,6 +38,8 @@ static ssize_t esm_token_write(struct file *f, const char __user *buf, >> static const struct proc_ops esm_token_fops = { >> .proc_read = esm_token_read, >> .proc_write = esm_token_write, >> + .proc_lseek = default_llseek, >> + >> }; >> >> static void ubuntu_host_cleanup(void) >> > >
On Wed, Jun 30, 2021 at 10:14:08AM +0100, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > BugLink: https://bugs.launchpad.net/1934110 > > Currently the lseek op is null and seeking on the esm-token procfs > file will cause an oops as detected by the stress-ng procfs stressor > as shown by the following splat: > > [ 942.470568] BUG: kernel NULL pointer dereference, address: 0000000000000000 > [ 942.471157] #PF: supervisor instruction fetch in kernel mode > [ 942.471724] #PF: error_code(0x0010) - not-present page > [ 942.472297] PGD 0 P4D 0 > [ 942.472867] Oops: 0010 [#1] SMP PTI > [ 942.473435] CPU: 2 PID: 5661 Comm: stress-ng Not tainted 5.13.0-9-generic #9 > [ 942.474012] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > [ 942.474599] RIP: 0010:0x0 > [ 942.475194] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. > [ 942.475792] RSP: 0018:ffffaacf80ff7eb8 EFLAGS: 00010246 > [ 942.476383] RAX: 0000000000000000 RBX: ffff9eaa8a175240 RCX: 0000000000000001 > [ 942.476986] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9eaa838d5800 > [ 942.477600] RBP: ffffaacf80ff7ed0 R08: 0000000000004000 R09: 0000000000000004 > [ 942.478203] R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 > [ 942.478800] R13: 0000000000000000 R14: ffffffffffffffea R15: ffff9eaa838d5800 > [ 942.479399] FS: 00007f998d487f00(0000) GS:ffff9eaaffc80000(0000) knlGS:0000000000000000 > [ 942.480006] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 942.480607] CR2: ffffffffffffffd6 CR3: 000000010a774002 CR4: 0000000000370ee0 > [ 942.481219] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 942.481855] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 942.482458] Call Trace: > [ 942.483052] proc_reg_llseek+0x4e/0x80 > [ 942.483646] ? __fdget_pos+0x43/0x50 > [ 942.484234] ksys_lseek+0x84/0xc0 > [ 942.484815] __x64_sys_lseek+0x1a/0x20 > [ 942.485412] do_syscall_64+0x61/0xb0 > [ 942.485966] ? asm_exc_page_fault+0x8/0x30 > [ 942.486476] entry_SYSCALL_64_after_hwframe+0x44/0xae > [ 942.486994] RIP: 0033:0x7f998d5c1cdb > [ 942.487512] Code: ff ff c3 0f 1f 40 00 48 8b 15 89 81 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa b8 08 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 59 81 0d 00 f7 d8 > [ 942.488593] RSP: 002b:00007ffdf61c5328 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 > [ 942.489148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f998d5c1cdb > [ 942.489710] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 > [ 942.490252] RBP: 0000000000000004 R08: 000001785e4740dd R09: 0000562dbebb9e50 > [ 942.490801] R10: 00007ffdf61c5300 R11: 0000000000000246 R12: 00007ffdf61c63f0 > [ 942.491354] R13: 00007ffdf61c53f0 R14: 0000000000000003 R15: 00000000000001e9 > > Fix this by using the generic lseek operation. > > Fixes: 71adefd254f2 ("UBUNTU: Add ubuntu-host module") > Signed-off-by: Colin Ian King <colin.king@canonical.com> Applied to impish, fixing the buglink. Thanks, -Andrea
On 30.06.21 11:14, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > BugLink: https://bugs.launchpad.net/bugs/1934110 > > Currently the lseek op is null and seeking on the esm-token procfs > file will cause an oops as detected by the stress-ng procfs stressor > as shown by the following splat: > > [ 942.470568] BUG: kernel NULL pointer dereference, address: 0000000000000000 > [ 942.471157] #PF: supervisor instruction fetch in kernel mode > [ 942.471724] #PF: error_code(0x0010) - not-present page > [ 942.472297] PGD 0 P4D 0 > [ 942.472867] Oops: 0010 [#1] SMP PTI > [ 942.473435] CPU: 2 PID: 5661 Comm: stress-ng Not tainted 5.13.0-9-generic #9 > [ 942.474012] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > [ 942.474599] RIP: 0010:0x0 > [ 942.475194] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. > [ 942.475792] RSP: 0018:ffffaacf80ff7eb8 EFLAGS: 00010246 > [ 942.476383] RAX: 0000000000000000 RBX: ffff9eaa8a175240 RCX: 0000000000000001 > [ 942.476986] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9eaa838d5800 > [ 942.477600] RBP: ffffaacf80ff7ed0 R08: 0000000000004000 R09: 0000000000000004 > [ 942.478203] R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 > [ 942.478800] R13: 0000000000000000 R14: ffffffffffffffea R15: ffff9eaa838d5800 > [ 942.479399] FS: 00007f998d487f00(0000) GS:ffff9eaaffc80000(0000) knlGS:0000000000000000 > [ 942.480006] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 942.480607] CR2: ffffffffffffffd6 CR3: 000000010a774002 CR4: 0000000000370ee0 > [ 942.481219] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 942.481855] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 942.482458] Call Trace: > [ 942.483052] proc_reg_llseek+0x4e/0x80 > [ 942.483646] ? __fdget_pos+0x43/0x50 > [ 942.484234] ksys_lseek+0x84/0xc0 > [ 942.484815] __x64_sys_lseek+0x1a/0x20 > [ 942.485412] do_syscall_64+0x61/0xb0 > [ 942.485966] ? asm_exc_page_fault+0x8/0x30 > [ 942.486476] entry_SYSCALL_64_after_hwframe+0x44/0xae > [ 942.486994] RIP: 0033:0x7f998d5c1cdb > [ 942.487512] Code: ff ff c3 0f 1f 40 00 48 8b 15 89 81 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa b8 08 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 59 81 0d 00 f7 d8 > [ 942.488593] RSP: 002b:00007ffdf61c5328 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 > [ 942.489148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f998d5c1cdb > [ 942.489710] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 > [ 942.490252] RBP: 0000000000000004 R08: 000001785e4740dd R09: 0000562dbebb9e50 > [ 942.490801] R10: 00007ffdf61c5300 R11: 0000000000000246 R12: 00007ffdf61c63f0 > [ 942.491354] R13: 00007ffdf61c53f0 R14: 0000000000000003 R15: 00000000000001e9 > > Fix this by using the generic lseek operation. > > Fixes: 71adefd254f2 ("UBUNTU: Add ubuntu-host module") > Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> > --- With the adjusted bug reference. -Stefan > ubuntu/ubuntu-host/ubuntu-host.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/ubuntu/ubuntu-host/ubuntu-host.c b/ubuntu/ubuntu-host/ubuntu-host.c > index 1abd402..a4c0636 100644 > --- a/ubuntu/ubuntu-host/ubuntu-host.c > +++ b/ubuntu/ubuntu-host/ubuntu-host.c > @@ -38,6 +38,8 @@ static ssize_t esm_token_write(struct file *f, const char __user *buf, > static const struct proc_ops esm_token_fops = { > .proc_read = esm_token_read, > .proc_write = esm_token_write, > + .proc_lseek = default_llseek, > + > }; > > static void ubuntu_host_cleanup(void) >
Acked-by: Tim Gardner <tim.gardner@canonical.com> On 6/30/21 3:14 AM, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > BugLink: https://bugs.launchpad.net/1934110 > > Currently the lseek op is null and seeking on the esm-token procfs > file will cause an oops as detected by the stress-ng procfs stressor > as shown by the following splat: > > [ 942.470568] BUG: kernel NULL pointer dereference, address: 0000000000000000 > [ 942.471157] #PF: supervisor instruction fetch in kernel mode > [ 942.471724] #PF: error_code(0x0010) - not-present page > [ 942.472297] PGD 0 P4D 0 > [ 942.472867] Oops: 0010 [#1] SMP PTI > [ 942.473435] CPU: 2 PID: 5661 Comm: stress-ng Not tainted 5.13.0-9-generic #9 > [ 942.474012] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > [ 942.474599] RIP: 0010:0x0 > [ 942.475194] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. > [ 942.475792] RSP: 0018:ffffaacf80ff7eb8 EFLAGS: 00010246 > [ 942.476383] RAX: 0000000000000000 RBX: ffff9eaa8a175240 RCX: 0000000000000001 > [ 942.476986] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9eaa838d5800 > [ 942.477600] RBP: ffffaacf80ff7ed0 R08: 0000000000004000 R09: 0000000000000004 > [ 942.478203] R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 > [ 942.478800] R13: 0000000000000000 R14: ffffffffffffffea R15: ffff9eaa838d5800 > [ 942.479399] FS: 00007f998d487f00(0000) GS:ffff9eaaffc80000(0000) knlGS:0000000000000000 > [ 942.480006] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 942.480607] CR2: ffffffffffffffd6 CR3: 000000010a774002 CR4: 0000000000370ee0 > [ 942.481219] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 942.481855] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 942.482458] Call Trace: > [ 942.483052] proc_reg_llseek+0x4e/0x80 > [ 942.483646] ? __fdget_pos+0x43/0x50 > [ 942.484234] ksys_lseek+0x84/0xc0 > [ 942.484815] __x64_sys_lseek+0x1a/0x20 > [ 942.485412] do_syscall_64+0x61/0xb0 > [ 942.485966] ? asm_exc_page_fault+0x8/0x30 > [ 942.486476] entry_SYSCALL_64_after_hwframe+0x44/0xae > [ 942.486994] RIP: 0033:0x7f998d5c1cdb > [ 942.487512] Code: ff ff c3 0f 1f 40 00 48 8b 15 89 81 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa b8 08 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 59 81 0d 00 f7 d8 > [ 942.488593] RSP: 002b:00007ffdf61c5328 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 > [ 942.489148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f998d5c1cdb > [ 942.489710] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 > [ 942.490252] RBP: 0000000000000004 R08: 000001785e4740dd R09: 0000562dbebb9e50 > [ 942.490801] R10: 00007ffdf61c5300 R11: 0000000000000246 R12: 00007ffdf61c63f0 > [ 942.491354] R13: 00007ffdf61c53f0 R14: 0000000000000003 R15: 00000000000001e9 > > Fix this by using the generic lseek operation. > > Fixes: 71adefd254f2 ("UBUNTU: Add ubuntu-host module") > Signed-off-by: Colin Ian King <colin.king@canonical.com> > --- > ubuntu/ubuntu-host/ubuntu-host.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/ubuntu/ubuntu-host/ubuntu-host.c b/ubuntu/ubuntu-host/ubuntu-host.c > index 1abd402..a4c0636 100644 > --- a/ubuntu/ubuntu-host/ubuntu-host.c > +++ b/ubuntu/ubuntu-host/ubuntu-host.c > @@ -38,6 +38,8 @@ static ssize_t esm_token_write(struct file *f, const char __user *buf, > static const struct proc_ops esm_token_fops = { > .proc_read = esm_token_read, > .proc_write = esm_token_write, > + .proc_lseek = default_llseek, > + > }; > > static void ubuntu_host_cleanup(void) >
On 30.06.21 11:14, Colin King wrote: > From: Colin Ian King <colin.king@canonical.com> > > BugLink: https://bugs.launchpad.net/1934110 > > Currently the lseek op is null and seeking on the esm-token procfs > file will cause an oops as detected by the stress-ng procfs stressor > as shown by the following splat: > > [ 942.470568] BUG: kernel NULL pointer dereference, address: 0000000000000000 > [ 942.471157] #PF: supervisor instruction fetch in kernel mode > [ 942.471724] #PF: error_code(0x0010) - not-present page > [ 942.472297] PGD 0 P4D 0 > [ 942.472867] Oops: 0010 [#1] SMP PTI > [ 942.473435] CPU: 2 PID: 5661 Comm: stress-ng Not tainted 5.13.0-9-generic #9 > [ 942.474012] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > [ 942.474599] RIP: 0010:0x0 > [ 942.475194] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. > [ 942.475792] RSP: 0018:ffffaacf80ff7eb8 EFLAGS: 00010246 > [ 942.476383] RAX: 0000000000000000 RBX: ffff9eaa8a175240 RCX: 0000000000000001 > [ 942.476986] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9eaa838d5800 > [ 942.477600] RBP: ffffaacf80ff7ed0 R08: 0000000000004000 R09: 0000000000000004 > [ 942.478203] R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 > [ 942.478800] R13: 0000000000000000 R14: ffffffffffffffea R15: ffff9eaa838d5800 > [ 942.479399] FS: 00007f998d487f00(0000) GS:ffff9eaaffc80000(0000) knlGS:0000000000000000 > [ 942.480006] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 942.480607] CR2: ffffffffffffffd6 CR3: 000000010a774002 CR4: 0000000000370ee0 > [ 942.481219] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 942.481855] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 942.482458] Call Trace: > [ 942.483052] proc_reg_llseek+0x4e/0x80 > [ 942.483646] ? __fdget_pos+0x43/0x50 > [ 942.484234] ksys_lseek+0x84/0xc0 > [ 942.484815] __x64_sys_lseek+0x1a/0x20 > [ 942.485412] do_syscall_64+0x61/0xb0 > [ 942.485966] ? asm_exc_page_fault+0x8/0x30 > [ 942.486476] entry_SYSCALL_64_after_hwframe+0x44/0xae > [ 942.486994] RIP: 0033:0x7f998d5c1cdb > [ 942.487512] Code: ff ff c3 0f 1f 40 00 48 8b 15 89 81 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 f3 0f 1e fa b8 08 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 59 81 0d 00 f7 d8 > [ 942.488593] RSP: 002b:00007ffdf61c5328 EFLAGS: 00000246 ORIG_RAX: 0000000000000008 > [ 942.489148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f998d5c1cdb > [ 942.489710] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 > [ 942.490252] RBP: 0000000000000004 R08: 000001785e4740dd R09: 0000562dbebb9e50 > [ 942.490801] R10: 00007ffdf61c5300 R11: 0000000000000246 R12: 00007ffdf61c63f0 > [ 942.491354] R13: 00007ffdf61c53f0 R14: 0000000000000003 R15: 00000000000001e9 > > Fix this by using the generic lseek operation. > > Fixes: 71adefd254f2 ("UBUNTU: Add ubuntu-host module") > Signed-off-by: Colin Ian King <colin.king@canonical.com> > --- > ubuntu/ubuntu-host/ubuntu-host.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/ubuntu/ubuntu-host/ubuntu-host.c b/ubuntu/ubuntu-host/ubuntu-host.c > index 1abd402..a4c0636 100644 > --- a/ubuntu/ubuntu-host/ubuntu-host.c > +++ b/ubuntu/ubuntu-host/ubuntu-host.c > @@ -38,6 +38,8 @@ static ssize_t esm_token_write(struct file *f, const char __user *buf, > static const struct proc_ops esm_token_fops = { > .proc_read = esm_token_read, > .proc_write = esm_token_write, > + .proc_lseek = default_llseek, > + > }; > > static void ubuntu_host_cleanup(void) > Applied to groovy:linux and hirsute:linux. Thanks, Kleber
diff --git a/ubuntu/ubuntu-host/ubuntu-host.c b/ubuntu/ubuntu-host/ubuntu-host.c index 1abd402..a4c0636 100644 --- a/ubuntu/ubuntu-host/ubuntu-host.c +++ b/ubuntu/ubuntu-host/ubuntu-host.c @@ -38,6 +38,8 @@ static ssize_t esm_token_write(struct file *f, const char __user *buf, static const struct proc_ops esm_token_fops = { .proc_read = esm_token_read, .proc_write = esm_token_write, + .proc_lseek = default_llseek, + }; static void ubuntu_host_cleanup(void)