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Marchesi" , Beau Belgrave , Florian Weimer , "Carlos O'Donell" , Masami Hiramatsu , Jiri Olsa , Arnaldo Carvalho de Melo , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich , "Steven Rostedt (Google)" , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Mathieu Desnoyers , Kees Cook , Sam James References: <20260505121718.3572346-1-jremus@linux.ibm.com> <20260505121718.3572346-13-jremus@linux.ibm.com> Content-Language: en-US From: Jens Remus Organization: IBM Deutschland Research & Development GmbH In-Reply-To: <20260505121718.3572346-13-jremus@linux.ibm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNTA4MDExMCBTYWx0ZWRfX2auMkqKWq9zH Kavt7w6o+5VsedWe6iM0PPPzgQRh4KusiXlnezRf3zsYGS/AO1+pdCbi00e+jrqb4oj3eBWBvWV uFfuZ3QmH6iquylpROzws0b7SgAsixvbXKJl/2XoCsQMiOcBzDZ4Sfxopeqpyf3FK5r1zbVIaFc V2Jt/34vzxbCvyRZ9+2jxCD98J3PrUFo7OFtFzWy+CYPa8CMyJPgXylbL9E+lBhVIIta6svQ0LC zZ9yPoSYIXlPir2H6EWqLJEZ4w5y3FgP/k9xswkHo6EFD+A6jap6eGBvGKpzN8WkHGk5sRLVrgj 40MLKp7jdLJYQmD02rkYvUkAQOGfdq6sQ2AjAIggoA6O0/PCv9QccQEhZ2HdxYkMB7X6jb236Lo sI8TWIY/ZYOgDVFiWfn+1gk8reKmStmBnQFIiIPrVAs7sV8BeDV3MS5LYxM/hAKi9+BloqOHFOw MOtkDQlPIadYUtb9lFg== X-Proofpoint-GUID: MwWipGJ7KURaSVIuB_RtelIYOy5mE4YQ X-Proofpoint-ORIG-GUID: Ocagi59Tk5URWX8c5UV7KnL-pAuRJkoL X-Authority-Analysis: v=2.4 cv=eu/vCIpX c=1 sm=1 tr=0 ts=69fdc055 cx=c_pps a=5BHTudwdYE3Te8bg5FgnPg==:117 a=5BHTudwdYE3Te8bg5FgnPg==:17 a=IkcTkHD0fZMA:10 a=NGcC8JguVDcA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=iQ6ETzBq9ecOQQE5vZCe:22 a=VnNF1IyMAAAA:8 a=VwQbUJbxAAAA:8 a=LFt20mCCc4CE-LtB3JUA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-05-07_02,2026-05-06_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 phishscore=0 lowpriorityscore=0 clxscore=1015 adultscore=0 suspectscore=0 malwarescore=0 bulkscore=0 impostorscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2604200000 definitions=main-2605080110 On 5/5/2026 2:17 PM, Jens Remus wrote: > From: Josh Poimboeuf > > Add a debug feature to validate all .sframe sections when first loading > the file rather than on demand. > > [ Jens Remus: Add support for SFrame V3. Add support for PC-relative > FDE function start offset. Adjust to rename of struct sframe_fre to > sframe_fre_internal. Use %#x/%#lx format specifiers. ] > diff --git a/kernel/unwind/sframe.c b/kernel/unwind/sframe.c > +static int safe_read_fde(struct sframe_section *sec, > + unsigned int fde_num, struct sframe_fde_internal *fde) > +{ > + int ret; > + > + if (!user_read_access_begin((void __user *)sec->sframe_start, > + sec->sframe_end - sec->sframe_start)) > + return -EFAULT; > + ret = __read_fde(sec, fde_num, fde); > + user_read_access_end(); > + return ret; > +} > +static int sframe_validate_section(struct sframe_section *sec) > +{ > + unsigned long prev_ip = 0; > + unsigned int i; > + > + for (i = 0; i < sec->num_fdes; i++) { > + struct sframe_fre_internal *fre, *prev_fre = NULL; > + unsigned long ip, fre_addr; > + struct sframe_fde_internal fde; > + struct sframe_fre_internal fres[2]; > + bool which = false; > + unsigned int j; > + int ret; > + > + ret = safe_read_fde(sec, i, &fde); Iterating over all FDEs may cause __read_fde() and thus safe_read_fde() to fail if one sframe section covers multiple text sections (regardless of whether it is also registered for multiple text sections), as __read_fde() checks whether the read FDE function start address is within [sec->text_start, sec->text_end[. See my related comments in my reply to [PATCH v14 05/19] unwind_user/ sframe: Add support for reading .sframe contents. > + if (ret) { > + dbg_sec("safe_read_fde(%u) failed\n", i); > + return ret; > + } > + Regards, Jens -- Jens Remus Linux on Z Development (D3303) jremus@de.ibm.com / jremus@linux.ibm.com IBM Deutschland Research & Development GmbH; Vorsitzender des Aufsichtsrats: Wolfgang Wendt; Geschäftsführung: David Faller; Sitz der Gesellschaft: Ehningen; Registergericht: Amtsgericht Stuttgart, HRB 243294 IBM Data Privacy Statement: https://www.ibm.com/privacy/