Dave Wysochanski a0e25f0a0d cachefiles: Fix oops with cachefiles_cull() due to NULL object ... When cachefiles_cull() calls cachefiles_bury_object(), it passes a NULL object. When this occurs, either trace_cachefiles_unlink() or trace_cachefiles_rename() may oops due to the NULL object. Check for NULL object in the tracepoint and if so, set debug_id to MAX_UINT as was done in 2908f5e101. The following oops was seen with xfstests generic/100. BUG: kernel NULL pointer dereference, address: 0000000000000010 ... RIP: 0010:trace_event_raw_event_cachefiles_unlink+0x4e/0xa0 [cachefiles] ... Call Trace: cachefiles_bury_object+0x242/0x430 [cachefiles] ? __vfs_removexattr_locked+0x10f/0x150 ? vfs_removexattr+0x51/0xd0 cachefiles_cull+0x84/0x120 [cachefiles] cachefiles_daemon_cull+0xd1/0x120 [cachefiles] cachefiles_daemon_write+0x158/0x190 [cachefiles] vfs_write+0xbc/0x260 ksys_write+0x4f/0xc0 do_syscall_64+0x3b/0x90 The following oops was seen with xfstests generic/290. BUG: kernel NULL pointer dereference, address: 0000000000000010 ... RIP: 0010:trace_event_raw_event_cachefiles_rename+0x54/0xa0 [cachefiles] ... Call Trace: cachefiles_bury_object+0x35c/0x430 [cachefiles] cachefiles_cull+0x84/0x120 [cachefiles] cachefiles_daemon_cull+0xd1/0x120 [cachefiles] cachefiles_daemon_write+0x158/0x190 [cachefiles] vfs_write+0xbc/0x260 ksys_write+0x4f/0xc0 do_syscall_64+0x3b/0x90 Fixes: 2908f5e101 ("fscache: Add a cookie debug ID and use that in traces") Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Link: https://listman.redhat.com/archives/linux-cachefs/2021-October/msg00009.html		2021-10-05 11:22:06 +01:00
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events	cachefiles: Fix oops with cachefiles_cull() due to NULL object	2021-10-05 11:22:06 +01:00
bpf_probe.h	trace: bpf: Allow bpf to attach to bare tracepoints	2021-01-20 14:13:59 -08:00
define_trace.h	tracepoint: Optimize using static_call()	2020-09-01 09:58:06 +02:00
perf.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2017-11-04 09:26:51 +09:00
syscall.h	tracepoints: Migrate to use SYSCALL_WORK flag	2020-11-16 21:53:15 +01:00
trace_events.h	tracing: Add trace_event helper macros __string_len() and __assign_str_len()	2021-08-17 11:47:52 -04:00