| Message ID | 20220815113931.53226-1-mairacanal@riseup.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/amdgpu: Fix use-after-free on amdgpu_bo_list mutex | expand |
Am 15.08.22 um 13:39 schrieb Maíra Canal: > If amdgpu_cs_vm_handling returns r != 0, then it will unlock the > bo_list_mutex inside the function amdgpu_cs_vm_handling and again on > amdgpu_cs_parser_fini. This problem results in the following > use-after-free problem: > > [ 220.280990] ------------[ cut here ]------------ > [ 220.281000] refcount_t: underflow; use-after-free. > [ 220.281019] WARNING: CPU: 1 PID: 3746 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x110 > [ 220.281029] ------------[ cut here ]------------ > [ 220.281415] CPU: 1 PID: 3746 Comm: chrome:cs0 Tainted: G W L ------- --- 5.20.0-0.rc0.20220812git7ebfc85e2cd7.10.fc38.x86_64 #1 > [ 220.281421] Hardware name: System manufacturer System Product Name/ROG STRIX X570-I GAMING, BIOS 4403 04/27/2022 > [ 220.281426] RIP: 0010:refcount_warn_saturate+0xba/0x110 > [ 220.281431] Code: 01 01 e8 79 4a 6f 00 0f 0b e9 42 47 a5 00 80 3d de > 7e be 01 00 75 85 48 c7 c7 f8 98 8e 98 c6 05 ce 7e be 01 01 e8 56 4a > 6f 00 <0f> 0b e9 1f 47 a5 00 80 3d b9 7e be 01 00 0f 85 5e ff ff ff 48 > c7 > [ 220.281437] RSP: 0018:ffffb4b0d18d7a80 EFLAGS: 00010282 > [ 220.281443] RAX: 0000000000000026 RBX: 0000000000000003 RCX: 0000000000000000 > [ 220.281448] RDX: 0000000000000001 RSI: ffffffff988d06dc RDI: 00000000ffffffff > [ 220.281452] RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffb4b0d18d7930 > [ 220.281457] R10: 0000000000000003 R11: ffffa0672e2fffe8 R12: ffffa058ca360400 > [ 220.281461] R13: ffffa05846c50a18 R14: 00000000fffffe00 R15: 0000000000000003 > [ 220.281465] FS: 00007f82683e06c0(0000) GS:ffffa066e2e00000(0000) knlGS:0000000000000000 > [ 220.281470] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 220.281475] CR2: 00003590005cc000 CR3: 00000001fca46000 CR4: 0000000000350ee0 > [ 220.281480] Call Trace: > [ 220.281485] <TASK> > [ 220.281490] amdgpu_cs_ioctl+0x4e2/0x2070 [amdgpu] > [ 220.281806] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] > [ 220.282028] drm_ioctl_kernel+0xa4/0x150 > [ 220.282043] drm_ioctl+0x21f/0x420 > [ 220.282053] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] > [ 220.282275] ? lock_release+0x14f/0x460 > [ 220.282282] ? _raw_spin_unlock_irqrestore+0x30/0x60 > [ 220.282290] ? _raw_spin_unlock_irqrestore+0x30/0x60 > [ 220.282297] ? lockdep_hardirqs_on+0x7d/0x100 > [ 220.282305] ? _raw_spin_unlock_irqrestore+0x40/0x60 > [ 220.282317] amdgpu_drm_ioctl+0x4a/0x80 [amdgpu] > [ 220.282534] __x64_sys_ioctl+0x90/0xd0 > [ 220.282545] do_syscall_64+0x5b/0x80 > [ 220.282551] ? futex_wake+0x6c/0x150 > [ 220.282568] ? lock_is_held_type+0xe8/0x140 > [ 220.282580] ? do_syscall_64+0x67/0x80 > [ 220.282585] ? lockdep_hardirqs_on+0x7d/0x100 > [ 220.282592] ? do_syscall_64+0x67/0x80 > [ 220.282597] ? do_syscall_64+0x67/0x80 > [ 220.282602] ? lockdep_hardirqs_on+0x7d/0x100 > [ 220.282609] entry_SYSCALL_64_after_hwframe+0x63/0xcd > [ 220.282616] RIP: 0033:0x7f8282a4f8bf > [ 220.282639] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 > 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 > 0f 05 <89> c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 > 00 > [ 220.282644] RSP: 002b:00007f82683df410 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > [ 220.282651] RAX: ffffffffffffffda RBX: 00007f82683df588 RCX: 00007f8282a4f8bf > [ 220.282655] RDX: 00007f82683df4d0 RSI: 00000000c0186444 RDI: 0000000000000018 > [ 220.282659] RBP: 00007f82683df4d0 R08: 00007f82683df5e0 R09: 00007f82683df4b0 > [ 220.282663] R10: 00001d04000a0600 R11: 0000000000000246 R12: 00000000c0186444 > [ 220.282667] R13: 0000000000000018 R14: 00007f82683df588 R15: 0000000000000003 > [ 220.282689] </TASK> > [ 220.282693] irq event stamp: 6232311 > [ 220.282697] hardirqs last enabled at (6232319): [<ffffffff9718cd7e>] __up_console_sem+0x5e/0x70 > [ 220.282704] hardirqs last disabled at (6232326): [<ffffffff9718cd63>] __up_console_sem+0x43/0x70 > [ 220.282709] softirqs last enabled at (6232072): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 > [ 220.282716] softirqs last disabled at (6232061): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 > [ 220.282722] ---[ end trace 0000000000000000 ]--- > > Therefore, remove the mutex_unlock from the amdgpu_cs_vm_handling > function, so that amdgpu_cs_submit and amdgpu_cs_parser_fini can handle > the unlock. > > Fixes: 90af0ca047f3 ("drm/amdgpu: Protect the amdgpu_bo_list list with a mutex v2") > Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> > Signed-off-by: Maíra Canal <mairacanal@riseup.net> Reviewed-by: Christian König <christian.koenig@amd.com> > --- > Thanks Melissa and Christian for the feedback on mutex_unlock. > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > index d8f1335bc68f..b7bae833c804 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > @@ -837,16 +837,12 @@ static int amdgpu_cs_vm_handling(struct amdgpu_cs_parser *p) > continue; > > r = amdgpu_vm_bo_update(adev, bo_va, false); > - if (r) { > - mutex_unlock(&p->bo_list->bo_list_mutex); > + if (r) > return r; > - } > > r = amdgpu_sync_fence(&p->job->sync, bo_va->last_pt_update); > - if (r) { > - mutex_unlock(&p->bo_list->bo_list_mutex); > + if (r) > return r; > - } > } > > r = amdgpu_vm_handle_moved(adev, vm);
On 08/15, Maíra Canal wrote: > If amdgpu_cs_vm_handling returns r != 0, then it will unlock the > bo_list_mutex inside the function amdgpu_cs_vm_handling and again on > amdgpu_cs_parser_fini. This problem results in the following > use-after-free problem: > > [ 220.280990] ------------[ cut here ]------------ > [ 220.281000] refcount_t: underflow; use-after-free. > [ 220.281019] WARNING: CPU: 1 PID: 3746 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x110 > [ 220.281029] ------------[ cut here ]------------ > [ 220.281415] CPU: 1 PID: 3746 Comm: chrome:cs0 Tainted: G W L ------- --- 5.20.0-0.rc0.20220812git7ebfc85e2cd7.10.fc38.x86_64 #1 > [ 220.281421] Hardware name: System manufacturer System Product Name/ROG STRIX X570-I GAMING, BIOS 4403 04/27/2022 > [ 220.281426] RIP: 0010:refcount_warn_saturate+0xba/0x110 > [ 220.281431] Code: 01 01 e8 79 4a 6f 00 0f 0b e9 42 47 a5 00 80 3d de > 7e be 01 00 75 85 48 c7 c7 f8 98 8e 98 c6 05 ce 7e be 01 01 e8 56 4a > 6f 00 <0f> 0b e9 1f 47 a5 00 80 3d b9 7e be 01 00 0f 85 5e ff ff ff 48 > c7 > [ 220.281437] RSP: 0018:ffffb4b0d18d7a80 EFLAGS: 00010282 > [ 220.281443] RAX: 0000000000000026 RBX: 0000000000000003 RCX: 0000000000000000 > [ 220.281448] RDX: 0000000000000001 RSI: ffffffff988d06dc RDI: 00000000ffffffff > [ 220.281452] RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffb4b0d18d7930 > [ 220.281457] R10: 0000000000000003 R11: ffffa0672e2fffe8 R12: ffffa058ca360400 > [ 220.281461] R13: ffffa05846c50a18 R14: 00000000fffffe00 R15: 0000000000000003 > [ 220.281465] FS: 00007f82683e06c0(0000) GS:ffffa066e2e00000(0000) knlGS:0000000000000000 > [ 220.281470] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 220.281475] CR2: 00003590005cc000 CR3: 00000001fca46000 CR4: 0000000000350ee0 > [ 220.281480] Call Trace: > [ 220.281485] <TASK> > [ 220.281490] amdgpu_cs_ioctl+0x4e2/0x2070 [amdgpu] > [ 220.281806] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] > [ 220.282028] drm_ioctl_kernel+0xa4/0x150 > [ 220.282043] drm_ioctl+0x21f/0x420 > [ 220.282053] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] > [ 220.282275] ? lock_release+0x14f/0x460 > [ 220.282282] ? _raw_spin_unlock_irqrestore+0x30/0x60 > [ 220.282290] ? _raw_spin_unlock_irqrestore+0x30/0x60 > [ 220.282297] ? lockdep_hardirqs_on+0x7d/0x100 > [ 220.282305] ? _raw_spin_unlock_irqrestore+0x40/0x60 > [ 220.282317] amdgpu_drm_ioctl+0x4a/0x80 [amdgpu] > [ 220.282534] __x64_sys_ioctl+0x90/0xd0 > [ 220.282545] do_syscall_64+0x5b/0x80 > [ 220.282551] ? futex_wake+0x6c/0x150 > [ 220.282568] ? lock_is_held_type+0xe8/0x140 > [ 220.282580] ? do_syscall_64+0x67/0x80 > [ 220.282585] ? lockdep_hardirqs_on+0x7d/0x100 > [ 220.282592] ? do_syscall_64+0x67/0x80 > [ 220.282597] ? do_syscall_64+0x67/0x80 > [ 220.282602] ? lockdep_hardirqs_on+0x7d/0x100 > [ 220.282609] entry_SYSCALL_64_after_hwframe+0x63/0xcd > [ 220.282616] RIP: 0033:0x7f8282a4f8bf > [ 220.282639] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 > 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 > 0f 05 <89> c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 > 00 > [ 220.282644] RSP: 002b:00007f82683df410 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > [ 220.282651] RAX: ffffffffffffffda RBX: 00007f82683df588 RCX: 00007f8282a4f8bf > [ 220.282655] RDX: 00007f82683df4d0 RSI: 00000000c0186444 RDI: 0000000000000018 > [ 220.282659] RBP: 00007f82683df4d0 R08: 00007f82683df5e0 R09: 00007f82683df4b0 > [ 220.282663] R10: 00001d04000a0600 R11: 0000000000000246 R12: 00000000c0186444 > [ 220.282667] R13: 0000000000000018 R14: 00007f82683df588 R15: 0000000000000003 > [ 220.282689] </TASK> > [ 220.282693] irq event stamp: 6232311 > [ 220.282697] hardirqs last enabled at (6232319): [<ffffffff9718cd7e>] __up_console_sem+0x5e/0x70 > [ 220.282704] hardirqs last disabled at (6232326): [<ffffffff9718cd63>] __up_console_sem+0x43/0x70 > [ 220.282709] softirqs last enabled at (6232072): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 > [ 220.282716] softirqs last disabled at (6232061): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 > [ 220.282722] ---[ end trace 0000000000000000 ]--- > > Therefore, remove the mutex_unlock from the amdgpu_cs_vm_handling > function, so that amdgpu_cs_submit and amdgpu_cs_parser_fini can handle > the unlock. > > Fixes: 90af0ca047f3 ("drm/amdgpu: Protect the amdgpu_bo_list list with a mutex v2") > Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> > Signed-off-by: Maíra Canal <mairacanal@riseup.net> > --- > Thanks Melissa and Christian for the feedback on mutex_unlock. > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > index d8f1335bc68f..b7bae833c804 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > @@ -837,16 +837,12 @@ static int amdgpu_cs_vm_handling(struct amdgpu_cs_parser *p) > continue; > > r = amdgpu_vm_bo_update(adev, bo_va, false); > - if (r) { > - mutex_unlock(&p->bo_list->bo_list_mutex); > + if (r) > return r; > - } > > r = amdgpu_sync_fence(&p->job->sync, bo_va->last_pt_update); > - if (r) { > - mutex_unlock(&p->bo_list->bo_list_mutex); > + if (r) > return r; > - } Nice catch, Maíra! Reviewed-by: Melissa Wen <mwen@igalia.com> > } > > r = amdgpu_vm_handle_moved(adev, vm); > -- > 2.37.2 >
Applied. Thanks! Alex On Mon, Aug 15, 2022 at 10:56 AM Melissa Wen <mwen@igalia.com> wrote: > > On 08/15, Maíra Canal wrote: > > If amdgpu_cs_vm_handling returns r != 0, then it will unlock the > > bo_list_mutex inside the function amdgpu_cs_vm_handling and again on > > amdgpu_cs_parser_fini. This problem results in the following > > use-after-free problem: > > > > [ 220.280990] ------------[ cut here ]------------ > > [ 220.281000] refcount_t: underflow; use-after-free. > > [ 220.281019] WARNING: CPU: 1 PID: 3746 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x110 > > [ 220.281029] ------------[ cut here ]------------ > > [ 220.281415] CPU: 1 PID: 3746 Comm: chrome:cs0 Tainted: G W L ------- --- 5.20.0-0.rc0.20220812git7ebfc85e2cd7.10.fc38.x86_64 #1 > > [ 220.281421] Hardware name: System manufacturer System Product Name/ROG STRIX X570-I GAMING, BIOS 4403 04/27/2022 > > [ 220.281426] RIP: 0010:refcount_warn_saturate+0xba/0x110 > > [ 220.281431] Code: 01 01 e8 79 4a 6f 00 0f 0b e9 42 47 a5 00 80 3d de > > 7e be 01 00 75 85 48 c7 c7 f8 98 8e 98 c6 05 ce 7e be 01 01 e8 56 4a > > 6f 00 <0f> 0b e9 1f 47 a5 00 80 3d b9 7e be 01 00 0f 85 5e ff ff ff 48 > > c7 > > [ 220.281437] RSP: 0018:ffffb4b0d18d7a80 EFLAGS: 00010282 > > [ 220.281443] RAX: 0000000000000026 RBX: 0000000000000003 RCX: 0000000000000000 > > [ 220.281448] RDX: 0000000000000001 RSI: ffffffff988d06dc RDI: 00000000ffffffff > > [ 220.281452] RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffb4b0d18d7930 > > [ 220.281457] R10: 0000000000000003 R11: ffffa0672e2fffe8 R12: ffffa058ca360400 > > [ 220.281461] R13: ffffa05846c50a18 R14: 00000000fffffe00 R15: 0000000000000003 > > [ 220.281465] FS: 00007f82683e06c0(0000) GS:ffffa066e2e00000(0000) knlGS:0000000000000000 > > [ 220.281470] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 220.281475] CR2: 00003590005cc000 CR3: 00000001fca46000 CR4: 0000000000350ee0 > > [ 220.281480] Call Trace: > > [ 220.281485] <TASK> > > [ 220.281490] amdgpu_cs_ioctl+0x4e2/0x2070 [amdgpu] > > [ 220.281806] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] > > [ 220.282028] drm_ioctl_kernel+0xa4/0x150 > > [ 220.282043] drm_ioctl+0x21f/0x420 > > [ 220.282053] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] > > [ 220.282275] ? lock_release+0x14f/0x460 > > [ 220.282282] ? _raw_spin_unlock_irqrestore+0x30/0x60 > > [ 220.282290] ? _raw_spin_unlock_irqrestore+0x30/0x60 > > [ 220.282297] ? lockdep_hardirqs_on+0x7d/0x100 > > [ 220.282305] ? _raw_spin_unlock_irqrestore+0x40/0x60 > > [ 220.282317] amdgpu_drm_ioctl+0x4a/0x80 [amdgpu] > > [ 220.282534] __x64_sys_ioctl+0x90/0xd0 > > [ 220.282545] do_syscall_64+0x5b/0x80 > > [ 220.282551] ? futex_wake+0x6c/0x150 > > [ 220.282568] ? lock_is_held_type+0xe8/0x140 > > [ 220.282580] ? do_syscall_64+0x67/0x80 > > [ 220.282585] ? lockdep_hardirqs_on+0x7d/0x100 > > [ 220.282592] ? do_syscall_64+0x67/0x80 > > [ 220.282597] ? do_syscall_64+0x67/0x80 > > [ 220.282602] ? lockdep_hardirqs_on+0x7d/0x100 > > [ 220.282609] entry_SYSCALL_64_after_hwframe+0x63/0xcd > > [ 220.282616] RIP: 0033:0x7f8282a4f8bf > > [ 220.282639] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 > > 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 > > 0f 05 <89> c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 > > 00 > > [ 220.282644] RSP: 002b:00007f82683df410 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > > [ 220.282651] RAX: ffffffffffffffda RBX: 00007f82683df588 RCX: 00007f8282a4f8bf > > [ 220.282655] RDX: 00007f82683df4d0 RSI: 00000000c0186444 RDI: 0000000000000018 > > [ 220.282659] RBP: 00007f82683df4d0 R08: 00007f82683df5e0 R09: 00007f82683df4b0 > > [ 220.282663] R10: 00001d04000a0600 R11: 0000000000000246 R12: 00000000c0186444 > > [ 220.282667] R13: 0000000000000018 R14: 00007f82683df588 R15: 0000000000000003 > > [ 220.282689] </TASK> > > [ 220.282693] irq event stamp: 6232311 > > [ 220.282697] hardirqs last enabled at (6232319): [<ffffffff9718cd7e>] __up_console_sem+0x5e/0x70 > > [ 220.282704] hardirqs last disabled at (6232326): [<ffffffff9718cd63>] __up_console_sem+0x43/0x70 > > [ 220.282709] softirqs last enabled at (6232072): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 > > [ 220.282716] softirqs last disabled at (6232061): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 > > [ 220.282722] ---[ end trace 0000000000000000 ]--- > > > > Therefore, remove the mutex_unlock from the amdgpu_cs_vm_handling > > function, so that amdgpu_cs_submit and amdgpu_cs_parser_fini can handle > > the unlock. > > > > Fixes: 90af0ca047f3 ("drm/amdgpu: Protect the amdgpu_bo_list list with a mutex v2") > > Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> > > Signed-off-by: Maíra Canal <mairacanal@riseup.net> > > --- > > Thanks Melissa and Christian for the feedback on mutex_unlock. > > --- > > drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 8 ++------ > > 1 file changed, 2 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > > index d8f1335bc68f..b7bae833c804 100644 > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c > > @@ -837,16 +837,12 @@ static int amdgpu_cs_vm_handling(struct amdgpu_cs_parser *p) > > continue; > > > > r = amdgpu_vm_bo_update(adev, bo_va, false); > > - if (r) { > > - mutex_unlock(&p->bo_list->bo_list_mutex); > > + if (r) > > return r; > > - } > > > > r = amdgpu_sync_fence(&p->job->sync, bo_va->last_pt_update); > > - if (r) { > > - mutex_unlock(&p->bo_list->bo_list_mutex); > > + if (r) > > return r; > > - } > Nice catch, Maíra! > > Reviewed-by: Melissa Wen <mwen@igalia.com> > > > } > > > > r = amdgpu_vm_handle_moved(adev, vm); > > -- > > 2.37.2 > >
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c index d8f1335bc68f..b7bae833c804 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c @@ -837,16 +837,12 @@ static int amdgpu_cs_vm_handling(struct amdgpu_cs_parser *p) continue; r = amdgpu_vm_bo_update(adev, bo_va, false); - if (r) { - mutex_unlock(&p->bo_list->bo_list_mutex); + if (r) return r; - } r = amdgpu_sync_fence(&p->job->sync, bo_va->last_pt_update); - if (r) { - mutex_unlock(&p->bo_list->bo_list_mutex); + if (r) return r; - } } r = amdgpu_vm_handle_moved(adev, vm);
If amdgpu_cs_vm_handling returns r != 0, then it will unlock the bo_list_mutex inside the function amdgpu_cs_vm_handling and again on amdgpu_cs_parser_fini. This problem results in the following use-after-free problem: [ 220.280990] ------------[ cut here ]------------ [ 220.281000] refcount_t: underflow; use-after-free. [ 220.281019] WARNING: CPU: 1 PID: 3746 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x110 [ 220.281029] ------------[ cut here ]------------ [ 220.281415] CPU: 1 PID: 3746 Comm: chrome:cs0 Tainted: G W L ------- --- 5.20.0-0.rc0.20220812git7ebfc85e2cd7.10.fc38.x86_64 #1 [ 220.281421] Hardware name: System manufacturer System Product Name/ROG STRIX X570-I GAMING, BIOS 4403 04/27/2022 [ 220.281426] RIP: 0010:refcount_warn_saturate+0xba/0x110 [ 220.281431] Code: 01 01 e8 79 4a 6f 00 0f 0b e9 42 47 a5 00 80 3d de 7e be 01 00 75 85 48 c7 c7 f8 98 8e 98 c6 05 ce 7e be 01 01 e8 56 4a 6f 00 <0f> 0b e9 1f 47 a5 00 80 3d b9 7e be 01 00 0f 85 5e ff ff ff 48 c7 [ 220.281437] RSP: 0018:ffffb4b0d18d7a80 EFLAGS: 00010282 [ 220.281443] RAX: 0000000000000026 RBX: 0000000000000003 RCX: 0000000000000000 [ 220.281448] RDX: 0000000000000001 RSI: ffffffff988d06dc RDI: 00000000ffffffff [ 220.281452] RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffb4b0d18d7930 [ 220.281457] R10: 0000000000000003 R11: ffffa0672e2fffe8 R12: ffffa058ca360400 [ 220.281461] R13: ffffa05846c50a18 R14: 00000000fffffe00 R15: 0000000000000003 [ 220.281465] FS: 00007f82683e06c0(0000) GS:ffffa066e2e00000(0000) knlGS:0000000000000000 [ 220.281470] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 220.281475] CR2: 00003590005cc000 CR3: 00000001fca46000 CR4: 0000000000350ee0 [ 220.281480] Call Trace: [ 220.281485] <TASK> [ 220.281490] amdgpu_cs_ioctl+0x4e2/0x2070 [amdgpu] [ 220.281806] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] [ 220.282028] drm_ioctl_kernel+0xa4/0x150 [ 220.282043] drm_ioctl+0x21f/0x420 [ 220.282053] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] [ 220.282275] ? lock_release+0x14f/0x460 [ 220.282282] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 220.282290] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 220.282297] ? lockdep_hardirqs_on+0x7d/0x100 [ 220.282305] ? _raw_spin_unlock_irqrestore+0x40/0x60 [ 220.282317] amdgpu_drm_ioctl+0x4a/0x80 [amdgpu] [ 220.282534] __x64_sys_ioctl+0x90/0xd0 [ 220.282545] do_syscall_64+0x5b/0x80 [ 220.282551] ? futex_wake+0x6c/0x150 [ 220.282568] ? lock_is_held_type+0xe8/0x140 [ 220.282580] ? do_syscall_64+0x67/0x80 [ 220.282585] ? lockdep_hardirqs_on+0x7d/0x100 [ 220.282592] ? do_syscall_64+0x67/0x80 [ 220.282597] ? do_syscall_64+0x67/0x80 [ 220.282602] ? lockdep_hardirqs_on+0x7d/0x100 [ 220.282609] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 220.282616] RIP: 0033:0x7f8282a4f8bf [ 220.282639] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00 [ 220.282644] RSP: 002b:00007f82683df410 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 220.282651] RAX: ffffffffffffffda RBX: 00007f82683df588 RCX: 00007f8282a4f8bf [ 220.282655] RDX: 00007f82683df4d0 RSI: 00000000c0186444 RDI: 0000000000000018 [ 220.282659] RBP: 00007f82683df4d0 R08: 00007f82683df5e0 R09: 00007f82683df4b0 [ 220.282663] R10: 00001d04000a0600 R11: 0000000000000246 R12: 00000000c0186444 [ 220.282667] R13: 0000000000000018 R14: 00007f82683df588 R15: 0000000000000003 [ 220.282689] </TASK> [ 220.282693] irq event stamp: 6232311 [ 220.282697] hardirqs last enabled at (6232319): [<ffffffff9718cd7e>] __up_console_sem+0x5e/0x70 [ 220.282704] hardirqs last disabled at (6232326): [<ffffffff9718cd63>] __up_console_sem+0x43/0x70 [ 220.282709] softirqs last enabled at (6232072): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 [ 220.282716] softirqs last disabled at (6232061): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 [ 220.282722] ---[ end trace 0000000000000000 ]--- Therefore, remove the mutex_unlock from the amdgpu_cs_vm_handling function, so that amdgpu_cs_submit and amdgpu_cs_parser_fini can handle the unlock. Fixes: 90af0ca047f3 ("drm/amdgpu: Protect the amdgpu_bo_list list with a mutex v2") Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Signed-off-by: Maíra Canal <mairacanal@riseup.net> --- Thanks Melissa and Christian for the feedback on mutex_unlock. --- drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)